WO2016040762A1 - Separation of emulsified and dissolved organic compounds from water - Google Patents

Abstract

Cellulose materials allow selective absorption of emulsified and dissolved hydrocarbons from water. Hydrophobic cellulosic surfaces are prepared in a gas-phase silanization process. The process of using 3,3,3-trifluoropropyl coated paper, cotton fabric and wool in separating hydrocarbon from water is described in details. A functional pillow is provided from encapsulation of untreated cotton wool into 3,3,3-trifluoropropyl functionalized cotton fabric container. The pillow repels water with 100% efficiency, and can absorb large volumes of hydrocarbon depending on its size. The purity of the treated water is >99% for emulsified oils. Additionally, hydrophobic paper can extract dissolved benzene from contaminated water.

Description

SEPARATION OF EMULSIFIED AND DISSOLVED ORGANIC COMPOUNDS

FROM WATER

RELATED APPLICATIONS

[0001] This application claims the benefit of priority to co-pending United States Application 62/049180, filed September 11, 2014, the entirety of which is incorporated by reference.

INCORPORATION BY REFERENCE

[0002] All patents, patent applications and publications cited herein are hereby incorporated by reference in their entirety. The disclosures of these publications in their entireties are hereby incorporated by reference into this application in order to more fully describe the state of the art as known to those skilled therein as of the date of the invention described herein

TECHNICAL FIELD

[0003] This technology relates generally to water purification. In particular, this invention relates to separation of dissolved or emulsified organic impurities from water.

BACKGROUND

[0004] With increasing environmental awareness and stringent regulations, efficient and cost-effective methods to separate oil from water, and to clean up oil spills are becoming increasingly desirable. A variety of materials have been used for oil/water separation including, but not limited to, synthetic membranes, Materials used for oil/water separation include (1) monolithic silicone-coated aerogels consisting of carbonaceous nanofibers prepared by template directed hydrothermal carbonization process and macroporous monoliths consisting of transparent and porous aerogels and xerogels made from

polymethylsilsesquioxane materials, and created by controlling the phase separation in a sol- gel process, (2) temporally stable super water-repellent and rough polythiophene films prepared separately from electrochemical and chemical polymerization processes, (3) organosilane surface which is superamphiphobic in air but superoleophilic under water, prepared using a phase separation reaction, (4) fluorinated and oxidized aluminum surfaces, (5) stainless steel mesh and polyester fabric materials produced by coating a blend of fluorinated polyhedral oligomeric silsesquioxane and cross-linked poly(ethylene glycol) diacrylate, (6) cryptomelane-type manganese oxide nanowires prepared by self-assembled, free-standing process, (7) nanocellulose aerogels functionalized with a nanoscopic layer of titanium dioxide (Ti0₂), and (8) fibrous carbon materials.

[0005] These materials have high absorption selectivities and capacities but are still difficult to fabricate on a large-scale. Alternative materials that are scalable, readily available, cheap, biodegradable, and renewable would be most suitable for environmental applications. Commercially available polypropylene fiber mats have been used for oil spill absorption. Unfortunately, 50% of the absorbed oil could not be recovered. Natural cellulose material absorbs both oil and water, and their functionalization resulted in low oil absorption capacity or in their application as filters.

[0006] Furthermore, separation of oil that is intimately mixed in the water, such as emulsions and solutions, presents even greater separation challenges.

SUMMARY

[0007] Functionalized (hydrophobic) paper is described for selective absorption of emulsified and dissolved oil from water. The method is simple, and since it is mainly capillary-action-driven, the oil removal process itself is highly energy efficient.

[0008] A method of purifying water including contacting contaminated water that includes an emulsified or solubilized hydrophobic organic component with a hydrophobically functionalized cellulosic body, the hydrophobic cellulosic body being non-wetting with water and permeable to the hydrophobic organic component; allowing the emulsified or solubilized hydrophobic organic component to permeate the functionalized cellulosic body while excluding at least a portion of the water; and collecting the hydrophobic organic component separate from the excluded water.

[0009] In one or more embodiments, the hydrophobically functionalized cellulosic body is functionalized with a siloxy moiety having pendant hydrophobic groups, and optionally the pendant hydrophobic groups comprise halo, perhalo or hydrocarbon groups. [0010] In one or more embodiments, the cellulosic body is configured for absorption of the hydrophobic organic component from contaminated water, and for example, the cellulosic body has high absorption capacity of at least 2000% and a porosity of greater than 50% and/or the cellulosic body has a thickness of at least 2 cm.

[0011] In one or more embodiments, the cellulosic body is configured for filtration of the hydrophobic organic component from contaminated water, and for example, the cellulosic body has a surface tension in the range of 43-48 mN/m to optimize roll of water from its surface.

[0012] In any of the preceding embodiments, the cellulosic body is made from matted paper or cotton, and for example, it can be a woven fabric.

[0013] In any of the preceding embodiments, the cellulosic body includes a

hydrophobically functionalized outer member surrounding an inner oil absorbent material, and optionally, the cellulosic body is anchored or weighted to remain submerged in the contaminated water and/or the cellulosic body includes a hydrophobically functionalized cotton fabric surrounding cotton wool.

[0014] In any of the preceding embodiments, the cellulosic body in is the form of a sheet, fabric or membrane.

[0015] In one or more embodiments, water is excluded from the cellulosic body by passing contaminated water over a surface of the membrane, fabric or sheet, wherein the hydrophobic organic component of the contaminated water permeates the cellulosic body and the excluded water is moved across the surface to a collection point, and optionally, the fiber density of the cellulosic body is selected to provide a high rate of oil permeation into the cellulosic body.

[0016] In one or more embodiments, contaminated water is applied as droplets to the surface.

[0017] In one or more embodiments, the hydrophobic functionalization is selected to provide a contact angle of water to allow the excluded water to roll as a drop off the surface. [0018] In another aspect, a device for separation of emulsified or solubilized hydrophobic organic components in water includes an outer encapsulating cover having a hydrophobically functionalized cellulosic body functionalized with a siloxy moiety having pendant hydrophobic groups, wherein the hydrophobic cellulosic body is non-wetting with water and permeable to a preselected hydrophobic organic component; an inner filler comprising an absorbent permeable to a preselected hydrophobic organic component; and an anchor for securing the device in a submerged location.

[0019] In some embodiments, the anchor comprises loads to increase the density of the device.

[0020] In some embodiments, the anchor comprises a tether for securing the device to an underwater location.

[0021] In another aspect, a device for separation of emulsified or solubilized hydrophobic organic components in water includes a membrane made up of a

hydrophobically functionalized cellulosic body functionalized with a siloxy moiety having pendant hydrophobic groups, wherein the hydrophobic cellulosic body is non-wetting with water and permeable to a preselected hydrophobic organic component.

[0022] In one or more embodiments, the device further includes a frame for holding the membrane; a receptacle positioned for receiving a preselected hydrophobic organic component; and a receptacle positioned for receiving excluded water.

[0023] In one or more embodiments, the hydrophobically functionalized cellulosic body of the device is functionalized with a siloxy moiety having pendant hydrophobic groups, and optionally, the pendant hydrophobic groups include halo, perhalo or hydrocarbon groups.

[0024] In one or more embodiments, the cellulosic body of the device is configured for absorption of the hydrophobic organic component from contaminated water.

[0025] In one or more embodiments, the cellulosic body of the device is configured for filtration of the hydrophobic organic component from contaminated water. [0026] In one or more embodiments, the cellulosic body of the device is made of paper or cotton.

[0027] Cellulose materials can be employed as sacrificial materials in water purification such as waste water treatment or large scale deepwater oil absorption. They can be used to reduce the chemical complexity of the waste water without adding extra cost to existing treatment process. These cellulose materials are inherently porous, and can be manufactured in large quantities at low cost. They can be chemically modified to alter their absorption capacity/selectivity, solubility, and hydrophobicity while maintaining porosity and tensile strength.

[0028] These and other aspects and embodiments of the disclosure are illustrated and described below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The invention is described with reference to the following figures, which are presented for the purpose of illustration only and are not intended to be limiting.

[0030] In the Drawings:

[0031] Figurel . Schematic illustration of the selective absorption of oil into

hydrophobic paper.

[0032] Figure 2. Absorption of oil (hexadecane) from water using, trichloro(3,3,3- trifluoropropyl)silane functionalized Gel Blotting (GB) 005 hydrophobic blotting paper (A) Photographs: (i) before, and (ii) after soaking hydrophobic paper in oil/water (1 :2, vol/vol) mixture for 35 min.; hexadecane was colored using oil blue. Insert in A,ii shows the purified water after removing the paper. (B) Photographs of oil/water mixture (1 :2, v/v): (i) before, and (ii) after placing unsilanized GB005 blotting paper in the mixture for 3.5 min. (C) Weight gain over 72 hours for the used 3,3,3-trifluoropropyl functionalized GB005 paper, compared to that of untreated paper.

[0033] Figure 3. (A) Absorption capacity of 3,3,3-trifluoropropyl functionalized cotton wool for a selected organic solvents and oils in terms of its weight gain, and oil recovery after squeezing of cotton. (B) Weight gain (closed circle points) and amount of oil recovered (open circle points) during n-hexadecane absorption and recovery/drying cycles by 3,3,3- trifluoropropyl functionalized GB005 blotting paper. (C) Image showing hydrophobic surface (contact angle of 150.8°) of the functionalized GB005 blotting paper after the 10th cycle of hexadecane absorption in B.

[0034] Figure 4. Absorption of emulsified oil/water (1 :2, vol/vol) mixture using 3,3,3- trifluoropropyl functionalized GB005 hydrophobic blotting paper (A) before, and (B) after soaking hydrophobic paper in mixture for 15 min.

[0035] Figure 5. Weight gain over 72 hours for 2 x 15 cm 3,3,3-trifluoropropyl functionalized GB005 paper, after removal from emulsified oil/water (1 :2, vol/vol)mixtures prepared using 200, 400, 600 and 1000 ppm of sodium dodecyl sulfate (SDS).

[0036] Figure 6. Thermogravimetric analysis of de-ionized (Dl)-water and treated water after placing -CH₂CH₂CF₃ functionalized GB005 in hexadecane-water mixtures (1 :2, vol/vol)

[0037] Figure 7. Thermogravimetric analysis of hexadecane, Dl-water, untreated and treated water aliquots of emulsified oil-water mixtures (1 :2, vol/vol) - both containing 1000 ppm SDS - respectively, before and after soaking -CH₂CH₂CF₃ functionalized GB005 blot paper

[0038] Figure 8. Typical thermogravimetric results obtained after the analysis of (A) Dl-water and (B) treated water aliquots from emulsified oil-water mixture (1 :2, vol/vol) containing 1000 ppm SDS.

[0039] Figure 9. Typical thermogravimetric data for untreated water aliquots from emulsified oil-water mixture (1 :2, vol/vol) containing 1000 ppm SDS.

[0040] Figure 10. Gas chromatography-mass spectrometric (GC-MS) analysis of dissolved benzene in untreated and treated water samples from benzene/water (1 :2, vol/vol) mixture, and 100 ppm standard benzene; treated water was obtained by placing octyl functionalized GB005 blotting paper in the mixture for 20 minutes

[0041] Figure 11. Absorption of oil (hexadecane) from water using a pillow consisting of trichloro(3,3,3-trifluoropropyl)silane functionalized hydrophobic cotton fabric (A): (i) before, and (ii) after soaking pillow in oil/water (1 :2, vol/vol) mixture for 5 seconds;

hexadecane was colored using oil blue. Insert in A,ii shows the purified water after removing pillow. (B) Photographs of oil/water mixture (1 :2, v/v): (i) before, and (ii) after placing pillow consisting of unsilanized fabric and cotton wool in the mixture for 5 seconds. (C) Weight gain after 20 days of drying used pillows, comparing silanized and unsilanized fabric barriers.

[0042] Figure 12 is a schematic illustration of a filtration mode for the removal of dissolved or emulsified hydrophobic organic impurities from water according to one or more embodiments.

[0043] Figure 13 describes a container for waste water treatment in which the mode of emulsified or dissolved oil/hydrocarbon removal is absorption according to one or more embodiments.

[0044] Figure 14 is a characterization of different (GB003, GB004 and GBN005) blotting papers according to (a) absorption capacity, (b) penetration rate and (c) porosity. Hexadecane was used as a model for oil in all experiments, and error bars represent standard deviation from the mean for 7 independent measurements.

[0045] Figure 15 shows bracketing of critical surface energies of CH₂CH₂(CF₂)₅CF₃ and CH₂CH₂CF₃ using a series of selected solvents (surface tension, mN.m) ranging from hexane (18.4), heptane (20.1), octane (21.6), decane (23.8), dodecane (25.4), hexadecane (27.5), nitrobenzene (43.9), ethylene glycol 947.7), glycerol (63.3) to water (72.2).

DETAILED DESCRIPTION

[0046] A simple method of water purification for use in resource limited environments where degradation of water environment is a major problem is provided. The cellulose-based separation system according to one or more embodiments can be used to alleviate environmentally related stress such as water pollution and scarcity. In certain embodiments, paper can be used for both industrial and domestic waste water treatments, as well as for large scale deepwater oil spills. This underutilized material (paper) is inherently porous, gas permeable, highly abundant and can be manufactured in large quantities at low cost.

Cellulose can be chemically modified to alter some basic physical properties such as absorption capacity/selectivity, solubility, hydrophobicity, etc. while maintaining other properties like color, air permeability, malleability, tensile strength and fiber orientation.

[0047] Functionalized- fibrous cellulosic materials can be used for selective absorption of emulsified or dissolved oil/hydrocarbon from water. The functionalized-cellulosic materials can be applicable for the treatment of produced water (a byproduct of the oil and gas drilling industries), and removal of dissolved pesticides, volatile organic compounds such as benzene, toluene, xylene, and ethylbenzene, and free floating, emulsified and dissolved oily and greasy substances from water. For free floating organic, about 99% separation efficiency can achieved using the functionalized paper whereas a 90% efficiency has been observed for dissolved hydrocarbons. Removal of more than 40%, more than 50%, more than 60%, more than 70%, more than 80%, or more than 90% of emulsified or solubilized hydrophobic organic compounds or oils is contemplated. Ranges of removal can be bounded by any of the values disclosed hereinabove.

[0048] The cellulose materials can be employed in various forms. For example, a highly porous and unfunctionalized cotton wool can be encapsulated into functionalized hydrophobic cotton fabric, and shaped as a "pillow". The functionalization treatment can be applied only to the pillow case, and so allowing easy disposal of the untreated cotton wool, e.g., through incineration. The functionalized pillow case is re-usable after washing. Here to, the process of removing oil is capillary-action-driven, the oil-water separation process is highly energy efficient.

[0049] The cellulosic based separation system can also be fashioned into other geometries such as sheets, fabrics, or weight adjusted paper blocks to optimize separation of organic impurities emulsified or dissolved in water or other polar solvent. In one

embodiment, functionalized-fibrous cellulose materials can be used as membranes to separate an oil or hydrophobic organic from water, e.g., in a filtration mode. Contaminated water can be passed over a functionalized cellulose membrane, so that oil is absorbed into (and through) the membrane and allowing the purified water to over the surface of the membrane to be collected in a capture receptacle. See, FIG. 12.

[0050] Cellulosic materials (cotton fabric, cotton wool, and cellulosic matted fibers, e.g., paper) can be functionalized through the self-assembly chemistry of silanization. Hydrophobic papers can be prepared through self-assembly chemistry of silanization by exposing the paper to the vapor of the silanizing reagent under vacuum (~20 psi) for at least 12 hours (Scheme 1). Slow silanization (with no heating) ensures that only the exposed fabric surface hydroxyl (OH) groups are derivatized, while leaving most of the OH groups involved in intermolecular hydrogen bonding within the fiber core unreacted.

[0051] The hydrophobic R groups useful in this work provide relatively high contact angle with water, e.g., a contact angle in the range of 146°-150° but are wetted by most hydrocarbons having surface tension in the range of 20 - 30 mN/m. Different silane reagents having different hydrophobic R groups (e.g., trichloro(lH,lH,2H,2H perfluorooctyl)silane, trichloro(octyl)silane, trichloro(3,3,3-trifluoropropyl)silane, and trichloro(phenethyl)silane) can be used for this purpose. These reagents allow such paper surface properties as hydrophobicity, absorption selectivity, and surface energies to be effectively tuned for a specific hydrocarbon/pollutant.

SB_jO^-ma

OH OH OH

L I

[0052] A range of cellulosic materials can be employed, and there are two modes by which they can be applied. (1) Absorption: cellulose materials with porosity >50% will be most useful. This category includes filter paper (90%), blotting paper (85%), ouate paper (82%), newsprint (65%) and packaging (50%>). Absorption capacity and oil penetration rate correlate directly with porosity (%). Both parameters can be maximized for oil absorption but size and thickness of the selected paper determines the maximum available volume for entrapment of oil. Though highly porous, filter papers (as they are sold) are ideal for absorption purpose as compared to blotting paper. (2) Filtration: commercially available filter papers are ideal for separation by filtration because of their high porosity, which allows the fastest penetration. Suitable cellulosic materials for use in filtration mode can have less absorption capacity than cellulosic materials used for absorption mode because the removed oil is intended to move through the membrane and into a receiving container. Tracing and capacitor paper have porosities of 2 and 1%, respectively, indicating that they are highly dense in cellulose fiber. Whilst this property imparts smoothness on the surface, it limits penetration. Calendaring is a process through which a rough paper surface can be smoothened without affecting porosity. In one or more embodiments, filter papers can be calendared before silanization for use as filters for oil/water separation.

[0053] By way of example, three different types of cellulose blotting papers (Whatman gel blotting (GB) papers GB003, 004 and 005) are described, which can be characterized according to their oil absorption capacity, rate of oil penetration and porosity. The device is self-supporting, and it has controllable properties. For example, one can easily functionalize the paper/fabric according to the compound to be removed - the silanization process is tunable, and can be easily executed. The absorption capacity of cellulose materials are fixed, and so one can control the size of the paper/pillow to suit the volume of affluent to be removed.

[0054] Whatman GB005 paper is used in the examples herein because it was superior in all three properties. GB005 paper was used as a model cellulose material for selective absorption of hexadecane from water. Silanization did not affect porosity and stiffness although the rate of oil penetration was reduced from 1.5 cm.min ¹ (for unfunctionalized) to 0.9 cm.min^"1 (functionalized) due to the reduction in surface energy after silanization.

Capillary action increases the absorption properties of the cellulosic fibers by filling partially the pores of the fibrous structure. Surface properties such as surface energy and contact angle are dependent on surface morphology. The density, defined as the ratio between the basis weight and the thickness, is related to porosity as follow: Ρ = - = Ρο - - ε eqn. 1

In equation 1, p, e, G, ε, and p₀ represent the apparent density, the thickness, the grammage, the porosity, and the fiber density, respectively.

[0055] After silanization, the porosity does not change. The oleophilic groups present at the surface of paper allows organics (i.e., oil or hydrocarbon) to permeate the surface pores while the mismatch in surface energies exclude water from wetting the paper. A pillow, in which un-functionalized cotton wool is encapsulated into a silanized/functionalized cotton fabric case was employed (See, FIG. 1). The combination of hydrophobic fabric and hydrophilic cotton wool into a pillow demonstrates one or more of the following

characteristics: 1) it enables efficient use of silanizing reagents by functionalizing only the fabric that can be used several time following washing after each use , 2) it offers a faster rate of selective oil/water absorption than paper, 3) the oil absorbed into the untreated cotton wool can be recovered with ease, and the cotton can be disposed by burning, and 4) the pillow can be made at low cost into different sizes.

[0056] Referring to FIG, 1, the oil permeates the hydrophobic fabric barrier (K_DI), then is driven by diffusion and capillary action (K_D2) in all directions to fill the pores in the cotton wool. This process is favorable as long as the fluid surface tension is lower than that of the surface, and K_D2 is greater than K_Di (the rate of oil permeation through the hydrophobic fabric barrier). In other words, wetting (or capillary action) should result in the minimization of the surface energy such that ΔΕ associated with equation 2 (i.e., the wetting of a dry surface) is negative: dry surface (energy, γ_5Α)→ wet surface (energy, y_LA + y_SL) eqn. 2 i. e. , ΔΕ = Y_sl + y_LA - y_SA eqn. 3 where YS_L, Y_LA, and YSA are solid-liquid, liquid-air, and solid-air interfacial energies respectively. ΔΕ is the change in free energy involved in wetting over a unit area. Static contact angle (Θ) measurements, related to surface energies, may characterize wetting.

Macroscopic surface hydrophobicity is also influenced by nano-scale characteristics such as structure and chemical composition. For example, when roughness (r defined as the ratio of actual liquid accessible area to geometrically projected area) is imparted to a solid surface, its wettability is changed according to equation 4. r cos0 = ^{r (y}^^"ysL) eqn. 4

YLA

[0057] Typical surface tensions of oils are in the range of 20 - 30 mN.m^"1 and that of water is 72 mN.m^"1, thus the free energy (ySA) of the silanized paper (or any cellulose material) surface can be in the range 30 < YSA < 72 mN/m in order to absorb oil while repelling water. Surfaces with the required surface tension can be engineered by selection of the appropriate silane reagents such as trichloro(3,3,3-trifluoropropyl)silane (9_water = 151 ± 2° on paper) and trichloro(octyl)silane (9_water = 144 ± 3° on paper). The critical surface energy (using zisman's plot for 3,3,3-trifluoropropyl (-CH₂CH₂CF₃) functionalized GB005 paper and cotton fabric to be 44 mN.m^"1 and 60 mN.m^"1 respectively. These critical surface energies allow for effective oil absorption (and exclusion of water from pores) since they lie in the 30 < TSA < 72 mN.m^"1 range. For comparison, paper surface prepared using perfluorooctyl (- CH₂CH₂(CF₂)₅CF₃) - critical surface energy of 20 mN.m^"1 - repels both oil and water.

[0058] To establish the absorption capacity of cellulosic materials, removal of free hexadecane (a diesel-like hydrocarbon) and pump oil from water using the -CH₂CH₂CF₃ coated cellulose materials was investigated. Figure 2A shows the results obtained by inserting two strips of 1.5x 15 cm² 3,3,3-trifluoropropyl functionalized GB005 paper in 33%

hexadecane in water (total mixture volume is 15 mL). For comparison, un-functionaiized GB005 paper was placed in similar hexadecane/water (1 :2, vol/vol) mixture (Figure 2B). The results show that 5 mL of free hexadecane can be soaked up into hydrophobic paper (Figure 2 A) in 35 minutes whilst also effectively excluding water from the paper surface/pores (Figure 2C). As expected, the un-functionaiized cellulose paper preferentially absorbed water - from the water/hexadecane mixture - in less than 5 minutes, after which the wet paper could not absorb hexadecane (Figure 2B).

[0059] Absorption capacity of -160% (measured as percent weight gain) was recorded for the hydrophobic paper as opposed to >300%> capacity for the un- functionalized paper, immediately upon removing the paper from the mixture (i.e., drying time = 0, Figure 2C). This initial weight gain by the un- functionalized paper is due to the absorption of water, which then evaporated resulting in a dramatic decrease in percent weight gain of the paper after 24 hours (Figure 2C). In contrast, the percent weight gain by the 3,3,3-trifluoropropyl functionaiized hydrophobic paper remained constant during the entire three-day monitoring period, indicating that the hydrophobic paper mostly absorbed hexadecane.

[0060] Maximum hexadecane absorption capacity, in weight gain, for GB005 paper was determined to be 190 ± 5% (Figure 3B, closed circle). This absorption capacity is low compared with other materials such as aerogels and magnesium nanowires having 2000% oil absorption capacity. In this regard, we selected cotton wool (with -2000% absorption capacity for most hydrocarbons), instead of paper, as a model material for large scale oil absorption from water (Figure 3A). Up to 85 ± 2% of the absorbed oil/hydrocarbon can be recovered by squeezing the cotton wool. Hexadecane absorbed into paper was recovered by (hexanes) solvent displacement; after this washing process, the used paper remained hydrophobic (9_water = 151 ±5° Figure 3C), even after the 10th wash. It should be noted from Figure 3B that the absorption capacity (closed circle) and oil recovery (open circle) from the 3,3,3-trifluoropropyl functionaiized paper remained the same after each cycle of hexadecane absorption and washing.

[0061] Emulsified and dissolved oils also pose severe environmental threat, and are often more difficult to remove from industrial water waste than free oil. The present invention has surprisingly demonstrated that cellulosic materials such as paper and cotton wool and woven fabrics are capable of efficiently removing emulsified and solubilized organic contaminants from water and other polar liquids. By way of example, emulsified hexadecane (an oily liquid) can be removed from water selectively, that is, oil is absorbed into the cellulosic absorbent system, while the water remains excluded.

[0062] To demonstrate the capability of hydrophobic paper in cleaning industrial waste water, emulsified oils of hexadecane in de-ionized water containing 200, 400, 600, and 1000 ppm of sodium dodecylsulfate (SDS) were purified using GB005 paper. The 3,3,3- trifluoropropyl functionaiized GB005 paper absorbed the emulsified oil in less than 15 minutes. (Figure 4). Weight gain experiments showed that the hydrophobic paper had mostly absorbed oil with no significant change (<3%>) in wetted paper weight after 3 days. There was however 15% reduction in weight gain by the paper which was inserted into the 1000 ppm SDS emulsified oil-water mixture. This weight loss corresponded to the amount of water absorbed (Figure 5) by the hydrophobic paper at 1000 ppm of SDS. As the surface tension of water is significantly reduced at 1000 ppm of SDS, it is hypothesized that the reduced surface tension permits water to permeate the 3,3,3-triflluoropropyl hydrophobic coating.

[0063] The water remaining after the absorption of the emulsified oil was analyzed using thermogravimetry in an attempt to further characterize the efficiency of the separation method. Water purities of >99% were observed for all emulsified oil/water mixtures tested using thermogravametric analysis (Figure 6 and 7). This is supported by the fact that the thermogravimetric results for all treated water show only one step transition with no residuals (See, curves 810, 820 and corresponding first derivative curves 810', 820' in Figure 8). Close look, however, of the thermogravimetric results from untreated aqueous portion of the 1000 ppm SDS emulsified oil/water show two step transition (See, curve 900 having transitions 910 and 920 in Figure 9). The first derivative curve 900' also indicated 2 distinct peak 910' and 920', thus confirming that the untreated water from emulsified oil/water mixture is a two component system (water and the dissolved hydrocarbon). The purity of this untreated aqueous portion is calculated to be 98.1%. This result, when compared with treated water (i.e., after removal of hexadecane with paper), establishes that the hydrophobic paper removed the dissolved hexadecane from water.

[0064] In another embodiment, paper can be used for the removal harmful

hydrocarbons such as benzene. Typical thermogravimetric data for untreated water aliquots from emulsified oil-water mixture (1 :2, vol/vol) containing 1000 ppm SDS This makes the removal of dissolved hydrocarbons such as benzene and toluene (solubilities of 1780 ppm and 535 ppm, respectively in water) from water particularly important. Here, mixtures consisting of 33% of the benzene in water were prepared using a stir bar at 1000 r.p.m. for 15 minutes. The free benzene component (~ 3 mL) of the mixtures was removed by placing 3><5 cm² hydrophobic paper (octyl functionalized GB005 paper) in the mixture for only a minute. After removal of the wet paper, a second and fresh 3><5 cm² hydrophobic paper was placed in the water for 20 minutes in order to remove the dissolved benzene component. After the second cycle of hydrophobic paper treatment, the resulting water was analyzed for the presence of benzene using gas chromatography/mass spectrometry (GC/MS). For

comparison, control water samples were prepared by decantation of the free benzene layer followed by GC/MS analysis of the remaining water. [0065] Results from GC/MS analysis of water samples taken from benzene/water (1 :2, vol/vol) mixture treated with octyl functionalized paper show significant reduction in the amount of dissolved benzene compared with control samples (Figure 10). The average integrated peak areas of the GC/MS signal obtained for the control untreated water and treated water samples are 406917 and 18342 (arbitrary units), respectively. Peak area for 100 ppm benzene standard and is 17539. This represents more than 20 times reduction in the amount of dissolved benzene, achieved simply via the insertion of octyl- functionalized hydrophobic paper into the contaminated water. We obtained similar results for toluene, as reported in Table 1.

Table 1: Gas chromatography-mass spectrometry analysis of dissolved toluene

Values for peak area represents mean response for 5 samples, with relative standard deviation less than 12%

Removal of dissolved benzene from a homogeneous aqueous solution can occur through the mechanism of surface tension driven absorption, which is not affected by the phase of affluent. Other technologies based on flotation, gravity, and coalescing mechanisms can only have a limited effect on removing dissolved organics.

[0066] In another embodiment, a continuous process for the removal of emulsified or dissolved organic impurities is described. The hydrophobic paper or fabric can be used in the filtration mode to separate oil from water. In this operation mode, the hydrophobic paper or fabric is placed on top of container; the whole assembly is then tilted at an appropriate angle, as is illustrated in Figure 12. For a sheet of hydrophobic paper or fabric, direct immersion is the only way for absorption, and for filtration mode the solution can be placed on top of the paper/fabric. An added advantage of using a long strip of paper as a pump is to passively move oil across long distances through capillary wicking. No power or electricity are needed. [0067] Upon contact of a drop containing emulsified or dissolved oil/hydrocarbon on the hydrophobic paper/fabric, the oil content of the droplet gets soaked-up into the hydrophobic paper/fabric, and the water portion rolls down the hydrophobic surface due the repulsive forces and the imposed angle. The rolling purified water can be collected.

[0068] The oil soaked into the hydrophobic surface will begin to drip from below the surface as its amount increases. The rate at which the oil drips down the surface depends largely of the strength of the adhesive/hydrophobic forces between the oil and the surface, but it will also depend on the pore size of the surface. Fabrics will be particularly effective in the filtration mode of water purification because fabrics of different fiber densities are readily available commercially.

[0069] When optimized, the fabric with the desired fiber density should have high rate of oil penetration, and high contact angle with water to allow it to slide as a drop and faster. Oil is expected to penetrate through the empty spaces available in the paper (determined by porosity). A paper with increased fiber density has little free volume, and thus making it difficult for oil to penetrate. For cotton fabric, however, a loosely woven fabric with smaller fiber density can easily allow both water and oil to pass irrespective of its surface properties (i.e., whether it has hydrophobic or hydrophilic bonded groups at its surface) and is therefore less preferred. A fiber density in the range of 85-395 threads per square inch, and in some embodiments 150 - 300 threads per square inch, can be used for selective oil absorption. A fiber density -80 threads per square inch is too low whereas values greater than 400 threads per square inch are too high to be used oil absorption. Both requirements can be controlled through silanization chemistry and calendaring process, in which the roughness of the surface can be controlled by applying high pressure.

[0070] For a large scale selective oil absorption from water, a pillow made from encapsulation of untreated cotton wool into a 3,3,3-trifluoropropyl functionalized cotton fabric can be used. The hydrophobic fabric serves as a barrier to water but permits the flux of hydrocarbons. The cotton wool serves as the main absorbing material - the size of the pillow determines the volume of oil to be absorbed. As an example, the pillow can be used for the separation of free hexadecane from water (Figure 13). In this experiment, 2x 14 cm² fabric containers were silanized using the gas-phase silanization procedure. Each silanized fabric container with one cotton ball (jumbo size purchased from CVS^® pharmacy). A second set of pillows involving un-silanized cotton fabric and wool were prepared as controls. The resulting pillows having hydrophobic versus hydrophilic fabric containers were separately inserted into 33% hexadecane in water (total volume of mixture is 15 mL). Both pillows absorbed the hexadecane within five seconds after insertion, but were kept in solution for ten more minutes. Weight gain experiments indicated that the pillow having un-silanized fabric case absorbed significant amount of water (>40% of initial pillow weight) within this extra ten minutes whereas no change in weight was recorded for the pillow with hydrophobic fabric case. The silanized fabric could be washed and re-used after removal of the cotton wool containing the absorbed oil. As shown in Figure 3A, the oil trapped in the wool can be recovered. This experiment represents an extra low-cost but using this simple methodology, large volumes of oil can be selectively absorbed from water.

[0071] Figure 13 is a schematic illustration of a system employing absorbent pillows for the removal of emulsified or dissolved organic impurities from water and describes a container for waste water treatment in which the mode of oil/hydrocarbon removal is absorption. The waste water may contain free, emulsified or dissolved oil/hydrocarbon. The container itself can be envisioned to have: (1) an opening through which the water to be treated is brought, (2) a vent to allow free flow of air, (3) a handle to access the interior of the container, and (4) a tap to remove purified water.

[0072] Hydrophobic paper or pillows can be used for this water treatment process. Since the pillows are light-weight (as they are made from cotton fabric and cotton wool), they tend to float on water. Different loads can therefore be added to different hydrophobic pillows so that their position inside the water can be adjusted for efficient contact and oil removal. The advantage associated with the ability to adjust the weight of the pillow is that for a multi-phase affluent, one can selectively remove specific phase into a particular pillow simply by adjusting the weight we add to the pillow. It becomes an efficient method to separate and purify multiple phase of liquids that are immiscible. Those pillows that are submerged under water can still prevent water from passing the fabric hydrophobic barrier.

[0073] Contact time, and size of the hydrophobic paper/pillow should be controlled depending on the amount of hydrocarbon to be absorbed. The container handle should be used to access/remove pillows that are saturated with oil. [0074] In conclusion, a simple gas-phase silanization method by which the surface energy of cellulose materials including paper, cotton fabric, and wool can be engineered for selective absorption of hydrocarbons from water is provided. The wide variety of

commercially available silane reagents should allow for easy tuning of surface energy of cellulose materials for removal of a specific organic pollutant. Effective and highly selective removal of 33% hexadecane (free and emulsified) from water was achieved by chemically bonding 3,3,3, trifluoropropyl hydrophobic group on paper (44 mN.m-1 surface energy) or cotton fabric (60 mN.m-1 surface energy). We have 2000% (by weight) capacity for the pillow configuration, and only 200% for paper. The cotton fabric absorbs the 33%

hexadecane at a faster rate (5 mL in 5 min) compared with paper (5 mL in 35 min). The cellulosic fabric was combined with cotton wool to create a pillow, which was then used in the oil absorption process. The cotton wool was not silanized, so allowing for effective and economical use of silane reagents. The method of oil absorption by cellulose materials can be applied in cases of large scale oil spill using the pillow configuration, and/or for treatment of industrial waste water. In the later application, the hydrophobic paper may be used as a sacrificial material to absorb bulk of the oil before subjecting the pre-treated water for further processing. In this case, the lifetime of membranes employed in the equipment can be extended.

[0075] According to weight gain measurements, the 3,3,3, trifluoropropyl

functionalized cellulose material can repel water close to 100% efficiency. This efficiency, however, reduce to 85% in the presence of 1000 ppm SDS by absorbing some water in addition to the desired oil. The purity of the treated water is >99% for mixtures that contained either free or emulsified oil. Separation efficiency for dissolved benzene and toluene using octyl functionalized paper was more than 90%. Unlike hydrophobic membranes used for oil absorption, paper is widely available, cheap, and biodegradable. These advantages are expected to impact environmental science through waste treatment, large scale oil spill cleanup and the removal of harmful dissolved organics.

1. EXPERIMENTAL PROCEDURE

[0076] 1.1 Materials and Reagents. All silane reagents for paper functionization including trichloro(3,3,3-trifluoropropyl)silane, trichloro(octyl)silane,

trichloro(phenethyl)silane, and trichloro(lH,lH,2H,2H perfluorooctyl)silane were obtained from Sigma Aldrich (St. Louis, MO, USA) except for Heptafluorobutyryl chloride which was purchased from 3B Scientific (Libertyville, IL, USA). All other organic reagents and hydrocarbons such as hexadecane, tridecane, dodecane, decane, octane, benzene, toluene, p- xylene, nitrobenzene, glycerol, ethylene glycol, oil blue N and sodium dodecylsulfate were obtained from Sigma Aldrich (St. Louis, MO, USA). Whatman gel blotting (GB) papers (GB003, GB004 and GB005) were purchased from VWR Int. Inc (Pittsburgh, PA, USA) whereas Whatman 3MM Chromatography blotting paper was obtained from Cole Parmer Instrument Co. (Chicago, IL, USA).

[0077] 1.2 Silanization. Paper silanization (Scheme 1) was conducted in a desiccator, under vacuum (20 psi) for 12 hours. Typically, 1 mL of silanization reagent was used for 4-5 sheets of blotting paper (15 x 15 cm). For all experiments, the required paper and fabric size was cut before silanization.

[0078] 1.3 Absorption Capacity. Maximum oil absorption capacity was determined by adding up to 320 hexadecane onto 1 cm2 blotting in an increment of 20 μί. The weight of the paper and absorbed oil was taken after allowing 30 s for oil to soak into the paper. A plot of oil absorbed (grams) versus volume added gives a breakthrough curve (Figure 14 A), and the saturation point on this graph was used as the maximum absorption capacity. For cotton wool, a ball of jumbo size cotton from CVS® pharmacy was placed (after silanization) in a large volume of hexadecane, and allowed to absorb the oil until it sinks to the bottom of the container. The weight of the wet cotton was recorded after removal and all unbound oil had dripped. Because of their low surface energies, cotton balls silanized with - CH2CH2(CF2)5CF3 did not sink in the oil even after 72 hours.

[0079] 1.4 Rate of Oil Penetration and Paper Porosity. For rate of oil penetration into blotting paper, strips of blotting papers (GB003, GB004 and GB005) of 1 cm wide and 7 cm long were employed. The papers were marked with pencil at each 1 cm. During the test, the paper strip was vertically dipped into 750 of hexadecane (colored with oil blue dye) such that the oil covered <2 mm of the paper. The time at which the rising liquid reached each 1 cm was recorded using stop watch. (Within the time of experiment, hexadecane evaporation was not a concern because of its low vapor pressure (0.0023 mmHg at 28o C); vapor pressure of water at 28o C is 28.4 mmHg). Having determined the corresponding time (t, seconds) for a giving height of rise (h, cm), dh/dt values were obtained through differentiation. A plot of dh/dt vs. 1/h yields a straight line whose slope gives a measure of the porosity of the paper medium (Figure 14C).

[0080] 1.5 Recovery of Absorbed Oil. To determine whether the hydrophobic paper can be re-cycled, the 3,3,3-trifluoropropyl functionalized GB005 paper (l x l cm) was first wetted completely by hexadecane. The absorbed oil in the paper was replaced by adding 3 mL of hexanes. After one hour of soaking the paper in the hexanes, the paper was resolved, and the amount of oil recovered was quantified after hexanes evaporation via rotary evaporator or leaving the mixture to stand under ambient conditions for overnight. The paper was placed again in 3 mL of hexanes for a second round of washing to completely remove all hydrocarbon after which the was dried for at least 12 h before using id for another round of oil absorption.

[0081] 1.6 Critical Surface Energy. Total wetting occurs when the surface tension of the wetting liquid is less than the critical energy of the surface (Figure 15). To estimate the critical energy of the silanized paper surface, we employed the method of bracketing. The basic idea in this bracketing experiment is that a liquid drop will wet a surface only when the wetted surface has a lower energy than the initial dry surface. Only such an exothermic reaction will proceed, and thus casting a drop of selected "inert" liquids onto a surface will lead to only two outcomes: category one, liquid droplet wets the surface and so its surface tension is lower than the critical energy of the surface, and category 2, liquid droplet does not wet the surface meaning the surface tension of the liquid is higher than the critical energy of the surface. The result of a series of such bracketing experiments is a quantitative measure of the critical energy of the surface if the surface tensions of the selected liquids are known. To do this, we tested different solvents (surface tensions in mN/m) including hexane (18.4), heptane (20.1), octane (21.6), decane (23.8), dodecane (25.4), hexadecane (27.5),

nitrobenzene (43.9), ethylene glycol (47.7), glycerol (63.3), and water (72.2) on - CH₂CH₂CF₃ and -CH₂CH₂(CF₂)₅CF₃ functionalized GB005 blotting papers. We found the critical surface energy for -CH₂CH₂CF₃ functionalized GB005 blotting paper to be in the range 43.9 - 47.7 mN/m (wets nitrobenzene but not ethylene glycol) whereas that for - CH₂CH₂(CF₂)₅CF₃ functionalized paper is in 21.6 - 23.8 mN/m range (wets octane but not decane. Another method by which critical energy can be estimated is through the Zisman plot which confirms the range of critical energies estimated by the bracketing approach. [0082] 1.7 Thermogrametric Analysis. The purity water content of the oil/water mixtures, (with and without added SDS surfactant) after oil separation was analyzed using thermogravimetry (TGA Q5000, TA instruments). Approximately 20 mg of the sample was heated from room temperature to 100° C at a rate of 5 °C/min, after which the temperature was held constant at 100° C for 20 min. The boiling point of hexadecane is 287° C, and so the loss in weight of water was used to estimate the purity of the treated water.

[0083] 1.8 Gas Chromatography-Mass Spectrometry (GC-MS). Removal of dissolved hydrocarbon from water was investigated by Waters Quattro micro GC-MS (/MS) (triple quadrupole MS with Agilent 6890 GC and CTC CombiPAL autosampler). 33% benzene, toluene and p-xylene in water were separately prepared, including fourth

hydrocarbon/water (1 :2, vol/vol) mixture, with the hydrocarbon portion consisting of benzene and toluene (1 :1 :2, vol/vol/vol). Hydrocarbon portion of the mixtures were selectively absorbed using octyl functionalized GB005 paper. Aliquots of each treated water were then analyzed using GC-MS and compared with the GC-MS data obtained for the corresponding water from untreated mixtures (See Table SI for GC-MS results for toluene).

[0084] 1.9 Contact angle measurement. All contact angle (static) measurements were conducted using a Rame-Hart 500-F4 goniometer. All contact angles reported in this work were the average (standard deviation <2%) of the left and right contact angles for a given drop, created by dispensing 10 μΐ, οΐ the liquid onto the surface; at least 10 measurements were performed on each substrate.

2. RESULTS AND DISCUSSION

[0085] 2.1 Paper selection. First, we investigated the use of paper for oil/water separation using three different cellulose blotting papers: GB003 (0.8 mm thick), GB004 (1.2 mm thick) and GB005 (1.5 mm thick). We characterized these papers according to their oil absorption capacity, rate of penetration and chose GB005 blotting paper for subsequent studies because it was superior in ail three properties (Figure 14).

[0086] We used hexadecane as a model compound for oil. It was determined that GB005 blotting paper has a higher (oil) absorption capacity (1.6 L/m2 of paper) compared to GB003 and GB004 (0.8 L/m2 of paper) blotting papers of the same size (Figure 14A). [0087] The rate of hexadecane penetration into blotting paper was determined to be 6 cm/4.0 min for GB005, which was much faster than that for GB004 (6 cm/7.6 min) and GB003 (6 cm/8.3 min).

[0088] We estimated the porosities (a parameter that is not available from

manufacturer) of the blotting papers by fitting the rate data to equation 5, a model that describes the rate of penetration (dh/dt) of a fluid into a porous medium: dh Av Bdq

— =— - eqn. 5

dt 477/1 877 ¹ where A and B are dependent only on the distribution of pore sizes in the medium, h is height of column, γ penetration tension, g acceleration due to gravity, and d and η are the density and viscosity of fluid respectively.

[0089] It follows that a plot of dh/dt versus 1/h gives a straight line, and the slope (Αγ/4η) of this line for a given liquid reflects the porosity of the medium. It can thus be inferred from Figure 14C that GB005 (slope = 0.071 cm²/s) blot paper is more porous than GB004 (slope = 0.031 cm²/s) and GB003 (0.030 cm²/s).

[0090] 2.2 Effect of silanization on paper properties. Silanization did not affect the absorption capacity although rate of oil penetration was reduced (Figure 14A and B). Oil penetration rate was reduced for the silanized paper because capillary action is directly related to the exothermicity of the wetting process; silanization reduced the surface free energy of the paper, and hence the amount of energy released upon wetting.

[0091] We determined in this work that extended silanization time (> 48 h) resulted in paper material that is brittle due to substantial reduction in the number of hydrogen bonding which give the paper its mechanical strength. This observation lends support to the expectation that within typical silanization time (<12 h), OH groups located inside the fiber core are not silanized. This is supported by measurement of the stiffness of the

functionalized-paper, and comparing it with that of the untreated paper (GB003, GB004 and

GB005). In all cases, we did not observe any change in paper stiffness after silanization, indicating that the mechanical strength remained unchanged after treatment. Scanning electron microscopy (SEM) analysis of GB005 paper show that the fibers within the bulk of the silanized paper are dense in, and can absorb fluid by entrapment in the pores or permeation into the cellulose microfibers. Capillary action increases the absorption properties of the paper by filling in the gaps of air that exist within the paper. In general, surface properties such as surface energy and contact angle are dependent on surface morphology. The morphology (roughness, fiber orientation or organization) and grammage (which is related to porosity, equation 6) of the paper does not change after silanization and this explains why the absorption capacity of silanized versus unsilanized paper remain the same.

Ρ = = Ρο (1 - ε) e ⁿ- ⁶ where p is apparent density, e is thickness, G is grammage, ε is porosity, and p₀ is actual fiber density in paper

[0092] 2.3 Absorption of emulsified oil. Absorption of oil emulsified using 1000 ppm sodium dodecylsulfate (SDS) was much slower than when 200, 400, and 600 ppm SDS were used for oil emulsification. This resulted in the absorption of oil as well as water (accounting for about 15% of total weight gain, Figure 5) over the 1 hour period.

[0093] Unless otherwise defined, used or characterized herein, terms that are used herein (including technical and scientific terms) are to be interpreted as having a meaning that is consistent with their accepted meaning in the context of the relevant art and are not to be interpreted in an idealized or overly formal sense unless expressly so defined herein. For example, if a particular composition is referenced, the composition may be substantially, though not perfectly pure, as practical and imperfect realities may apply; e.g., the potential presence of at least trace impurities (e.g., at less than 1 or 2%) can be understood as being within the scope of the description; likewise, if a particular shape is referenced, the shape is intended to include imperfect variations from ideal shapes, e.g., due to manufacturing tolerances. Percentages or concentrations expressed herein can represent either by weight or by volume.

[0094] Although the terms, first, second, third, etc., may be used herein to describe various elements, these elements are not to be limited by these terms. These terms are simply used to distinguish one element from another. Thus, a first element, discussed below, could be termed a second element without departing from the teachings of the exemplary embodiments. Spatially relative terms, such as "above," "below," "left," "right," "in front," "behind," and the like, may be used herein for ease of description to describe the relationship of one element to another element, as illustrated in the figures. It will be understood that the spatially relative terms, as well as the illustrated configurations, are intended to encompass different orientations of the apparatus in use or operation in addition to the orientations described herein and depicted in the figures. For example, if the apparatus in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term, "above," may encompass both an orientation of above and below. The apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. Further still, in this disclosure, when an element is referred to as being "on," "connected to," "coupled to," "in contact with," etc., another element, it may be directly on, connected to, coupled to, or in contact with the other element or intervening elements may be present unless otherwise specified.

[0095] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting of exemplary embodiments. As used herein, singular forms, such as "a" and "an," are intended to include the plural forms as well, unless the context indicates otherwise.

[0096] It will be appreciated that while a particular sequence of steps has been shown and described for purposes of explanation, the sequence may be varied in certain respects, or the steps may be combined, while still obtaining the desired configuration. Additionally, modifications to the disclosed embodiment and the invention as claimed are possible and within the scope of this disclosed invention. By way of non-limiting example, although the invention is described with reference to removal of contaminants from water, purification of other hydrophilic or polar solvents, in particular, water immiscible liquids, is contemplated.

[0097] What is claimed is :

Claims

1. A method of purifying water, comprising:

contacting contaminated water comprising an emulsified or solubilized hydrophobic organic component with a hydrophobically functionalized cellulosic body, the hydrophobic cellulosic body being non- wetting with water and permeable to the hydrophobic organic component; allowing the emulsified or solubilized hydrophobic organic component to permeate the functionalized cellulosic body while excluding at least a portion of the water; and

collecting the hydrophobic organic component separate from the excluded water.

2. The method of claim 1, wherein the hydrophobically functionalized cellulosic body is functionalized with a siloxy moiety having pendant hydrophobic groups.

3. The method of claim 1, wherein the pendant hydrophobic groups comprise halo, perhalo or hydrocarbon groups.

4. The method of claim 1, wherein the cellulosic body is configured for absorption of the hydrophobic organic component from contaminated water.

5. The method of claim 4, wherein the cellulosic body has high absorption capacity of at least 2000% and a porosity of greater than 50%.

6. The method of claim 4, wherein the cellulosic body has a thickness of at least 2 cm.

7. The method of claim 1, wherein the cellulosic body is configured for filtration of the hydrophobic organic component from contaminated water.

8. The method of claim 7, wherein the cellulosic body has a surface tension in the range of 43-48 mN/m to optimize roll of water from its surface.

9. The method of claim 1, wherein the cellulosic body comprises matted paper.

10. The method of claim 1, wherein the cellulosic body comprises cotton.

11. The method of claim 1 , wherein the cellulosic body comprises a woven fabric.

12. The method of claim 1, wherein the cellulosic body comprises a hydrophobically functionalized outer member surrounding an inner oil absorbent material.

13. The method of claim 12, wherein the cellulosic body is anchored or weighted to remain submerged in the contaminated water.

14. The method of claim 12, wherein the cellulosic body comprises a hydrophobically functionalized cotton fabric surrounding cotton wool.

15. The method of claim 1, wherein the cellulosic body in is the form of a sheet, fabric or membrane.

16. The method of claim 15, wherein water is excluded from the cellulosic body by passing contaminated water over a surface of the membrane, fabric or sheet, wherein the hydrophobic organic component of the contaminated water permeates the cellulosic body and the excluded water is moved across the surface to a collection point.

17. The method of claim 16, wherein contaminated water is applied as droplets to the surface.

18. The method of claim 16, wherein the fiber density of the cellulosic body is selected to provide a high rate of oil separation.

19. The method of claim 16, wherein the hydrophobic functionalization is selected to provide a contact angle of water to allow the excluded water to roll as a drop off the surface.

20. A device for separation of emulsified or solubilized hydrophobic organic components in water, comprising: an outer encapsulating cover comprising a hydrophobically functionalized cellulosic body functionalized with a siloxy moiety having pendant hydrophobic groups, wherein the hydrophobic cellulosic body is non-wetting with water and permeable to a preselected hydrophobic organic component; an inner filler comprising an absorbent permeable to a preselected hydrophobic organic component; and an anchor for securing the device in a submerged location.

21. The device of claim 20, wherein the anchor comprises loads to increase the density of the device.

22. The device of claim 20, wherein the anchor comprises a tether for securing the device to an underwater location.

23. A device for separation of emulsified or solubilized hydrophobic organic components in water, comprising: a membrane comprised of a hydrophobically functionalized cellulosic body functionalized with a siloxy moiety having pendant hydrophobic groups, wherein the hydrophobic cellulosic body is non-wetting with water and permeable to a preselected hydrophobic organic component.

24. The device of claim 23, further comprising: a frame for holding the membrane; a receptacle positioned for receiving a preselected hydrophobic organic component; a receptacle positioned for receiving excluded water.

25. The device of claim 20 or 23, wherein the hydrophobically functionalized cellulosic body is functionalized with a siloxy moiety having pendant hydrophobic groups.

26. The device of claim 20 or 23, wherein the pendant hydrophobic groups comprise halo, perhalo or hydrocarbon groups.

27. The device of claim 23 wherein the cellulosic body is configured for absorption of the hydrophobic organic component from contaminated water.

28. The device of claim 23, wherein the cellulosic body is configured for filtration of the hydrophobic organic component from contaminated water.

29. The device of claim 20 or 23, wherein the cellulosic body comprises paper.

30. The device of claim 20 or 23, wherein the cellulosic body comprises cotton.