WO1990004455A1

WO1990004455A1 - Oil spill absorbent material

Info

Publication number: WO1990004455A1
Application number: PCT/US1988/003584
Authority: WO
Inventors: Anthony Ceaser
Original assignee: Anthony Ceaser
Priority date: 1988-10-17
Filing date: 1988-10-17
Publication date: 1990-05-03

Abstract

The present invention relates to a water-repellent polymeric composition, having a substantial number of the hydroxyl groups of the polymeric skeleton which, optionally, are reacted with a metal/ammonium complex. These compositions find particular utility as absorbents for environmental, lipophilic contaminants, both of waters (i.e. oil spills) and of soils and similar solids. They can also be utilized in other applications where a water-repellent cellulose is necessary, i.e., water-repellent insulation, water-repellent papers, etc. Additionally, this invention relates to methods for producing a water-repellent composition and to methods for utilizing the water-repellent compositions as absorbents in applications where lipophilicity and water-repellency is desirable.

Description

O I L S PILL ABSORBENT MATER IAL BACKGROUND OF THE INVENTION

The recovery and disposal of petroleum, especially petroleum crude that is spilled at sea is a very serious problem. Failure to control the spilled oil can lead to the contamination of miles of shoreline with concomitant damage to natural flora and fauna, as well as to types of man-made installations that are built into the water.

Numerous methods have been devised for the clean-up of such oil spills. Surfactants have been applied to the oil to disperse it, but these are usually so rapidly diluted by the sea currents that they are ineffective. Absorbent materials which are heavier than water have been used to absorb the oil, but these sink to the bottom, and retain the oil at the bottom of the sea. This results in a slow liberation of the oil, damage to the flora and fauna at the sea bottom and pollution over a greater distance. Absorbent materials which do not sink in the water have most advantageously been utilized, typically in a sock type container for use as a boom. However, most of these also absorb water and thus do not perform in a completely satisfactory manner.

The decontamination of soils contaminated with oils and organic, lipophilic contaminants as well as heavy metals is a problem to which no economically satisfactory solution has yet been offered. The fusing of such soils is an approach which is exceedingly costly and regrettably, has been found insufficiently secure against long term leaching.

SUMMARY OF THE INVENTION

The present invention discloses a novel, substantially dry hydrophobic, lipophilic absorbent material comprising: an absorbent substrate comprising substantially of polymeric material having labile hydroxy groups in its skeleton, the polymer suitably being a carbohydrate in powder, granular or fibre form and a complex reacted therewith, said complex being formed from (b) at least one fatty acid

SUBSTITUTE SHEET having from 12 to 20 carbon atoms; and (c) at least one water-soluble hydroxide or oxide or salt, suitably the carbonate, sulfate, acetate or chloride salt of the group of metals which form coordination complexes with substituted or unsubstituted ammonium ion; (d) an ammonium ion donor; (e) a catalytic amount of a strong alkaline metal hydroxide; and sufficient water to solubilize the metal salt, the ammonium ion donor and the strong alkali metal hydroxide; the resultant mixture is then dried.

This composition may then be utilized to absorb water- insoluble organic liquids, such as oil spills. One method of the present invention comprises contacting the surface layers of the water- insoluble organic liquid floating on water, such as oil, with this novel composition, absorbing the organic liquid thereon, and removing the resultant absorbed composition.

The novel hydrophobic, lipophilic absorbent compositions, which have a specific gravity less than 1 may also be intimate mixed with contaminated solids, suitably soils having a specific gravity greater than 1 , for example by ploughing them in.

The contaminated solids and absorbent materials are permitted to remain in intimate contact for a time sufficient to enable the absorbent material to reach its absorptive capacity.

in a further embodiment further quantities of absorbent material are added into intimate contact with said contaminated solids, until no change in color of the newly added absorbent material is noted.

A first suspension of the mixture of said previously contaminated solids and said absorbent materials is prepared in a sufficient quantity of water to permit the separation of said first suspension into readily separable layers of absorbent material, aqueous phase and previously contaminated solids and the absorbent materials from said first suspension, suitably by skimming them from the top of the

EET aqueous phase. Suitably the absorbent material is a polymeric substrate in powder, granular or fibre form.

In yet another embodiment further quantities of absorbent material are added to the aqueous phase after removal of the initially suspended absorbent material from the first suspension step, the further absorbent material is mixed with at least said aqueous phase to provide a second suspension, the further absorbent material is permitted to form a separable layer and the further absorbent material is separated from said second suspension. Suitably, this process is repeated until no color change is observed in the suspended absorbent material.

In yet a further refinement of the process it is possible to carry out the additional step of purifying the aqueous phase by contacting it with solid absorbent materials capable of absorbing heavy metal ions and small amounts of lipophilic materials.

While the best results in decontaminating contaminated solids are obtained using the novel absorbents produced in accordance with the present application, the process of decontamination of solids is not so limited. A degree of decontamination may be achieved by using any hydrophobic, lipophilic polymeric absorbent with a specific gravity less than 1. The level of absorbency is enhanced however by the absence of labile groups in the skeleton of polymer, which may be natural or synthetic. Thus while nylons and polyamides may be used, where the polymer is not treated as described above, the best results are obtained by highly hydrophibic polymers such as polyethylene or polypropylene. Styropfoam "acorns" may also be used.

DETAILED DESCRIPTION OF THE INVENTION

The fibrous substrate utilized in making the novel absorbent of the present invention can be derived from cellulose, wool or other fibrous material having an active hydroxyl group. When it is derived from cellulose, the fibrous substrate to be utilized comprises

SUBSTITUTE SHEET hydrophiiic cellulose fibers derived from any cellulose-containing naturally occurring material, such as wood, cotton, straw, grass, bast, ramie, linen, bagasse, hemp, sisal or jute. Cellulose pulp fibers liberated from lignocellulosic material by any pulping process such as chemical cellulose fibers, mechanical

Iignocellulose fibers, chemi-mechanical fibers, semi-mechanical fibers, and reject fibers from pulp mills or paper board mills are particularly preferred. Peat fibers liberated from matured peat can also be used.

The fibrous substrate may comprise from about 50 to about 80% w/w suitably about 60% w/w of the final product.

Where high purity is required in the substrate, powdered or granular starch may be similarly employed. The fatty acid having from 12 to 20 carbon atoms may be selected from any of the saturated or unsaturated fatty acids, such as lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, ricinoleic acid, linoleic acid, linolenic acid , as well as the mixed fatty acids derived from tallow, coconut oil, linseed oil, cottonseed oil, corn oil, fish oil, peanut oil, soybean oil, safflower oil and other vegetable and animal oils.

The fatty acid may comprise from about 2 to about 3.5 mole % suitably about 5 mole % of the complex.

The water-soluble hydroxide or oxide, or salt such as the acetate, carbonate, sulfate, nitrate or chloride of the group of metals which form coordination complexes with the ammonium ion is selected from any of the various salts which perform this function, for instance, the hydroxides, oxides, carbonates, sulfates and chlorides of copper, cobalt, zinc, chromium, and zirconium. Of these th hydroxides, oxides and carbonates of copper, cobalt, zinc, chromium and zirconium are preferred. Especially preferred are th hydroxides, oxides and carbonates of zinc and copper. The metals may comprise from about 5% to about 40 mole % suitably about 20 mole % of the complex.

The ammonium ion donor may be any compatible ammonium source for example, ammonium hydroxide, or a salt such as ammonium carbonate, chloride or sulfate or a volatile organic amine. The function of the ammonium ion donor is when combined with water to immediately form, in situ, a coordination complex with the metal ion. This metal-ammonium complex, in combination with the fatty acid, reacts with the three reactive hydroxyl groups on the cellulose molecule to impart water- repellency and oil- affinity to the cellulose fibers. It is of interest to note that while the presence of an ammonium ion donor is required for the formation of the product of the present invention, analysis of the product does not show the presence of any nitrogen. Further, if an ammonium complex is formed with the metal while not in contact with the fatty acid and the substrate, the desired product is not formed.

The ammonium ion may be used in the form

....R¹ + . \ R³- N-R²

H

wherein R¹, R² and R³ are hydrogen or lower alkyl of 1-5 carbon atoms or where R¹ and R² are joined together, there is formed a nitrogen containing heterocycle of 5 - 8 members and having 0 or 1 additional heteroatoms in the ring selected from the group consisting of N, S, or O .

The ammonium ion may exist as the ion derived from primary amines such as ethylamine or n-butylamine, as secondary amines such as diethylamine or dipropylamine, as tertiary amines such as trimethyl

UBSTITUTE SHEET amiπe. As heterocycies there may be used saturated, unsaturated and aromatic heterocycies such as pyrrolidine, piperidine, piperazine, morpholine, 2-pyrroline, ϊndoline, imϊdazoline, pyridine, isothiazoie and indole. These are listed purely for exemplification and not as limitations of scope of the invention. The ammonium (as ammonia) may comprise from about 30 to about 90 mole % suitably about 75 mole% of the complex.

The reaction between the metal-ammonium complex, the fatty acid and the carbohydrate moieties is suitably, but not critically, catalyzed by the addition of a strong alkali metal hydroxide in a solution of water. Typically, sodium or potassium hydroxide is utilized due to their availability and cost, but others may also be utilized with equal facility.

The alkali metal hydroxide may comprise from about 0.2 to about 0.05 mole % suitably about 0.1 mole % of the complex.

The amount of water is selected so as to solubiiize the metal salt, the ammonium ion donor and the alkali metal hydroxide.

Typically, the composition of the present invention is produced by mixing together, in solid, dry form, the cellulose, wool or other fibrous material, the metallic salt, the ammonium ion donor and the fatty acid.

There are several modes in which this procedure may be carried out. The substrate can be mixed with the fatty acid per se or the metal source per se or with both together; the first and third alternatives being preferred due to the substantial water insolubility of fatty acids. If the ammonium donor is solid and dry it may be added to any one of the foregoing three mixtures.

If either the acid or the metal is not initially mixed in, or if the ammonium donor to be used is not solid, then the omitted components are mixed with the aqueous phase, which preferably, but not critically will include a catalytic amount of a strong alkali metal hydroxide dissolved in the water and sprayed into the agitated mixture. Usually a ratio of 1 part by weight of water to 2 parts by weight of substrate is employed. The resultant mixture is then dried and is ready for usage. The reaction is normally somewhat exothermic, thus usually more continued agitation for from about 15 to about 60 minutes is usually sufficient to produce substantially dry material. External drying sources such as external application of heat, injection of dry air or hot dry air or any other drying means known to the art may be used.

In a related embodiment, larger amounts of water, say up to a ratio of 4 parts by weight of water to 1 part by weight of substrate may be employed than are needed to solvate the complex components. The thus produced "mush" is then extruded into fibers, thin strips, tubules, granules or the like, which are then dried. Such a format is preferred when dust formation may be a problem.

The absorbent composition normally is used in granulated or shredded form. The fibrous composition can be granulated or shredded after preparation using conventional granulating or shredding apparatus. The resulting fibers can be assembled as a mass on water with the aid of a floating boom or other means, and guided towards the floating liquid to be absorbed.

An important feature of the composition of the present invention is that the water repellency of the composition is retained even after contact with organic solvents. This means that the composition can be used to absorb oil with the oil then being extracted from the composition with suitable organic solvents, thus enabling the reuse of the composition. This stability to solvent extraction indicates that the fatty acid has chemically reacted with the fibrous composition and is not merely a surface modification as in the prior art. This stability is additionally important because it

SUBSTITUTE SHEET means that the water- repeliency of the^' composition is retained in applications where contact with organic solvents can be expected, e.g., spill clean-up. Tests, using various organic solvents such as aliphatic, aromatic and chlorinated solvents, have been run on the compositions of the present invention which indicated that up to 10 consecutive extractions with organic solvents did not appreciably affect their water repeliency.

The fibrous embodiment of the present invention can be additionally utilized in the manufacture of water- repellent paper goods by utilizing the fibers as substrate for a further manufacturing process. Thus, the granules or shredded form can be used in conventionally manufacturing processes to form water-repellent goods such as cardboard, paper plates, etc.

The absorbent composition of the present invention is advantageously stable over a period of at least twelve months. When tested in cellulose waterproofing tests, samples that had been stored for nine (9) months showed no difference in water-repellency from freshly made samples.

The hydrophobic, lipophilic absorbent compositions, which are intimately mixed with contaminated solids, suitably soils for example by ploughing them in are employed in a ratio of from about 25 to about 250 cubic meters of absorbent per hectare meter of soil. The nature of the mixing process is not critical. Ploughing to a depth of 50 to 100 cms is satisfactory. The water content of the soils is also not critical, however better mixing is obtained where the soil is in a "light" as opposed to "heavy" or waterlogged condition.

The contaminated solids and absorbent materials are initially permitted to remain in intimate contact for from about 12 to about 48 hours, usually 12 hours is sufficient to enable the absorbent material to reach its absorptive capacity. If desired, further quantities of absorbent material are added and allowed intimate contact with the contaminated solids for similar periods of time, until no change in color of the newly added absorbent material is noted.

A first suspension of the mixture of said previously contaminated solids and said absorbent materials is prepared in a conventional settling tank. The amount is water is not critical, it has been found that between 2 and 10 kilolitres of water per cubic meter of the mixed previously contaminated solids and absorbent is sufficient to permit the separation of said first suspension into readily separable layers of absorbent material, aqueous phase and previously contaminated solids. The absorbent materials are removed from this suspension, suitably by skimming them from the top of the aqueous phase.

If desired, fresh absorbent material is added to the aqueous phase after removal of the initially suspended absorbent material from the first suspension step and mixed with at least the aqueous phase to provide a second suspension, the further absorbent material is permitted to form a new separable layer which is then again separated from this second suspension. Suitably, this process is repeated until no color change is observed in the suspended absorbent material.

In yet a further refinement of the process it is possible to carry out the additional step of removing a major portion of the residual heavy metal ions and small amounts of lipophilic materials present in the previously contaminated solids. In this additional step,the aqueous phase is contacted with solid absorbent materials capable of absorbing heavy metal ions and small amounts of lipophilic materials. Such materials are known in the art. Especially suitable are those disclosed in applicant^'s US Patents 4,436,645 and 4,517,095, which are incorporated herein by reference. It is especially preferred to coat such materials on the fibers of filter substrates through which the aforesaid aqueous phase is passed. The solids in the suspension tank are then resuspended, permitted to settle and the process repeated until the

SUBSTITUTE SHEET solid residues in the tank meet predetermined levels of purity. They are then dewatered in the conventional manner and utilized as clean fill.

The efficiency of the extraction is inversely dependent on the polarity of the contaminant. Thus motor oils are reduced from about a level of about 1000 ppm to a level of about 5ppm, on the other hand catechol is only reduced from a level of 100 ppm to a level of about 78 pmm. This is not a serious disadvantage since the more polar contaminants are reduced in the washing steps by procedures known in the art for example by moving the pH of the wash water to the acid or base side, as appropriate to solvate the contaminant, ie acid for amines and base for phenols.

The following Examples describe in detail the compositions and processes of the present invention. It will be apparent to those skilled in the art that many modifications, both of materials and methods, may be practiced without departing from the purpose and intent of this disclosure.

EXAMPLE I

50.0 kg. fine ground waste paper

1.5 kg. zinc oxide 5.0 kg. ammonium carbonate

1.5 kg. stearic acid

0.1 kg. sodium hydroxide

25.0 kg. water

The first four ingredients are added dry to a high speed powder mixer of the vertical screw type running at about 250 rpm and blended. The sodium hydroxide is then dissolved in the water and added as spray to the circulating mixture. After about 30 minutes of agitation after the water/sodium hydroxide addition is complete, the product is sufficiently dry to pack off.

This product "wets out" in fresh or salt water only after 144-400 hours, as compared to unmodified cellulose fiber which wets out in 1-5 minutes.

EXAMPLE ll

50.0 kg. fine ground cotton fiber

1.8 kg. copper carbonate 1.5 kg. myristic acid

4.5 kg. ammonium hydroxide

0.1 kg. potassium hydroxide

22.0 kg. water

The dry cotton fiber, copper carbonate and myristic acid are combined and blended. The ammonium hydroxide, potassium hydroxide and water are then added as a spray to the circulating mixture as in Example I. After about 30 minutes of further agitation the mixture is dry enough to pack off.

SUBSTITUTE SHEET 100.0 kg. Wood flour

1.3 kg. oleic acid 2.1 kg. Chrome alum

5.0 kg. ammonium hydroxide

0.1 kg. sodium hydroxide

35.0 kg. water

The first two ingredients are added dry to a high speed powder mixer of the vertical screw type running at about 250 rpm and blended. The remaining three components are then dissolved in the water and added as spray to the circulating mixture. After about 30 minutes of agitation after the water/sodium hydroxide addition is complete, the product is sufficiently dry to pack off.

EXAMPLE IV

100.0 kg. Wood flour 2.1 kg. Chrome alum 1.3 kg. oleic acid

5.0 kg. ammonium hydroxide 0.1 kg. sodium hydroxide 35.0 kg. water

The dry wood flour, chrome alum and oleic acid are combined and blended. The ammonium hydroxide, sodium hydroxide and water are then added as a spray to the circulating mixture as in Example I. After about 30 minutes of further agitation the mixture is dry enough to pack off.

SUB HEET 100.0 kg. ground corn cob 1.65 kg. coconut fatty acid 1.85 kg. copper sulfate

8.0 kg. morpholine 0.25 kg. sodium hydroxide 25.0 kg. water

The first two ingredients are added dry to a high speed powder mixer of the vertical screw type running at about 250 rpm and blended.

Ingredients 3,4 & 5 are then dissolved in the water and added as spray to the circulating mixture. After about 30 minutes of agitation after the water/sodium hydroxide addition is complete, the product is sufficiently dry to pack off.

EXAMPLE VI

100.0 kg. ground corn cob 1.65 kg. coconut fatty acid 1.85 kg. copper sulfate

8.0 kg. morpholine 0.25 kg. sodium hydroxide 25.0 kg. water

The dry corn cob, copper sulfate and fatty acid are combined and blended. The morpholine sodium hydroxide and water are then added as a spray to the circulating mixture as in Example l. After about 30 minutes of further agitation the mixture is dry enough to pack off.

SUBSTITUTE SHEET EXAMPLE VII

100.0 kg. Cold-water soluble Potato Starch

5.0 kg. copper hydroxide 5.0 kg. stearic acid

25.0 kg. ammonium hydroxide

10.0 kg. water

The potato starch, copper hydroxide and stearic acid are combined and blended. The ammonium hydroxide and water are then added as a spray to the circulating mixture as in Example I. After about 30 minutes of further agitation the mixture is dry enough to pack off.

EXAMPLE VIII

Kerosine Pickup

A test tank 3m x 3m x 1m deep is filled to a depth of about 50 cm with water and 10 liters of kerosine is floated thereon. 1 kg of cellulose treated in accordance with example I is added and swept across the water surface with a floating boom. All of the kerosine is absorbed and the absorbent material is then scooped up. The kerosine is recovered by distillation under reduced pressure.

In accordance with the above procedure, but in place of kerosine, there may be employed Bunker C fuel oil, toluol or trichloroethylene which are all similarly absorbed.

Utilizing the above procedure, similar results are obtained using any of the other absorbents produced by Example II through VII, in place of that of Example I. Comparative testing

Samples were prepared in accordance with Example 11 of Hoechst German OLS 23 58 808. These samples when exposed to water became waterlogged in 5 minutes. Extraction with 1 ,1 ,1- trichloroethane removed 75% of the chromium originally added to the substrate.

Further samples were prepared in accordance with the Quilon (TM) Bulletin published by the manufacturer, Dupont. The product, prepared using hexamethylenetetramine as the complexing amine at pH 3, yielded a product which became waterlogged in 1.5 hours and similarly, extraction with 1 ,1 ,1- trichloroethane removed 75% of the chromium originally added to the substrate.

Absorbency Testing

Cellulose treated in accordance with Example I is preweighed and packed loosely into a flat bottomed box equipped with a drain. Kerosine was dripped into the box until it appeared that no more was being absorbed, ie there was a wet appearance. The box was then tilted at 35o to the horizontal and all surplus kerosine drained off. The contents of the box were then weighed. The amount of kerosine absorbed was 10 times the weight of the cellulose.

The foregoing experiment was repeated for Bunker C fuel oil, toluol and trichloroethylene. The pick up was 14x, 9x and 12x the weight of the cellulose respectively. Similar results are obtained using any of the other absorbents produced by Example II through VII.

EXAMPLE IX

Clean garden soil (1 Outers) was contaminated with a mixture of organic and inorganic materials consisting of:

Used motor oil 10 ml Catechol 1ml

SUBSTITUTE SHEET The substantially dry contaminated soil was mixed with absorbent prepared in accordance with Example 1 (3g) and allowed to remain in contact for 12 hours. The mixture is then suspended in water (50 liters) by agitation at 300 rpm for 10 minutes, allowed to settle for 2 hrs and the absorbent removed. A further amount of absorbent (5g) was mixed with the aqueous phase (not reslurried). The aqueous phase was removed (but not discarded). A further amount of water (50 liters) was added and the soil reslurried (300 rpm) and allowed to settle. The combined waste water were filted through a filter column containing material for the removal of polar pollutants disclosed in US Patent 4 517 095. The residual soil was dried and extracted with 1,1,1 -trichloroethane in accordance with the E.P.A. Standard Oil/Water test, and subsequently with 4-aminoantipyrene in accordance with the standard E.P.A. test for phenols. Analysis of the extracts showed: Used motor oil 5ppm

Catechol 78ppm

EXAMPLE X

An area of approximately 0.2 hectare is preploughed to a depth of approximately 65 cm to loosen the soil. Absorbent treated cellulose (prepared in accordance with example I, 20 kilolitres is spread over the ploughed field in a substantially even layer, the field is then repioughed at right angles to the original ploughing. After 24 hours the entire ploughed soil/ absorbent mixture is removed with a scoop loader and transported to a settling tank where it is mixed with water (50 kiloliters per 10 kiloliters of soil/cellulose mix), slurried for 1 hour, allowed to settle for 3 hrs and the absorbent removed by skimming. It is preferred to add sufficient sodium chloride and environmentally acceptable acid, ie hydrochloric or sulfuric acid to provide a 1% sodium cholride and pH 5 level in the aqueous phase to reduce emulsification.

The procedure of Example X may be repeated utilizing any of the absorbants produced in accordance with Examples II through VII Similarly there may be utilized untreated absorbent polyethylene or .

SUBSTITUTE SHEET

Claims

CLAIMS:

1. A process for the preparation of a hydrophobic, lipophilic absorbent material which comprises mixing: a) the absorbent substrate comprising substantially of a polymeric carbohydrate in powder, granular or fibre form, with at least one component selected from a set consisting of b) at least one a fatty acid having from 12 to 20 carbon atoms; c) at least one water soluble hydroxide, oxide, or salt of the group of metals which form complexes with an ammonium ion and d') an ammonium ion donor in dry solid form, and adding thereto at least one component selected from group (b) or group (c) provided that a component of the group selected had not been previously admixed, and at least one component selected from d") an ammonium ion in liquid phase provided a component of group

(d') had not been previously admixed and e) sufficient water to solubilize said added components when water soluble, and drying the resultant mixture.

2. A process according to Claim 1 further comprising adding (f) a catalytic amount of a strong alkali metal hydroxide in the second stage of the process.

3. A process according to Claim 1, wherein the second step comprises spraying the aqueous phase into the agitated mixture of components of the first step.

4. A process according to Claim 1 , wherein the absorbent material is a fibrous cellulose material, wherein the fatty acid is stearic or myristic acid, wherein the metal oxide is zinc oxide, and wherein the metal salt is copper sulfate or copper carbonate.

5. A substantially dry hydrophobic, lipophilic absorbent material comprising : a) an absorbent substrate comprising substantially of a polymeric carbohydrate in powder, granular or fibre form, previously reacted with b) at least one fatty acid having from 12 to 20 carbon atoms; c) at least one water soluble hydroxide or oxide, or salt of the group of metals which form complexes with ammonium ion; d) an ammonium ion donor; and e) sufficient water to solubilize (c) and (d) in accordance with the procedures of Claim 1 , said reacted material having been dried after reaction.

6. A substantially dry hydrophobic, lipophilic absorbent material prepared in accordance with the procedures of Claim 2.

7. An absorbent material of Claim 5 wherein the ammonium ion is substituted in the form

....R, + . \ R₃- N-R₂

H

wherein R_v R₂ and R₃ are hydrogen or lower alkyl of 1-5 carbon atoms or where R₁ and R₂ are joined together, there is formed a nitrogen containing heterocycle of 5 - 8 members and having 0 or 1 additional heteroatoms in the ring selected from the group consisting of N, S, or O .

8. An absorbent material of Claim 5 wherein the substrate is in fibrous form selected from the group consisting of cellulose material or starch .

9. An absorbent material of claim 5 wherein the ammonium ion donor is aqueous ammonia, aqueous morpholine or aqueous pyridine.

SUBSTITUTE SHEET 10. An absorbent fibrous material of Claim 5 comprising : from about 50 to about 80% w/w of fibrous material of (a), from about 5 to about 15% w/w of components (b) through (e) of the complex and water to 100%.

11. A material of Claim 5, wherein the mole ratios of:

(b) as acid : (c) as metal ion :(d) as ammonia are from ~2 to ~5 % : from 5 to -40 % : from -30 to 90 %.

12. A material according to Claim 5, wherein the fatty acid is stearic or myristic acid.

13. A material of Claim 5 wherein the metal is zinc, copper or chromium.

14. A material according to Claim 5, wherein the metal oxide is zinc oxide.

15. A water-repellent fibrous cellulose material of Claim 8 wherein a sufficient amount of water is used in (e) to form an extrudable mass, said mass having been extruded and the extrudate dried.

16. A process for the absorption of surface layers of water- insoluble organic liquids floating on water which comprises contacting the surface layer with water-repellent fibrous material of Claim 5.

17. A process according to Claim 15, wherein the water-soluble organic liquid is a petroleum oil.

18. A process for extracting lipophilic contaminants from contaminated solids having a specific gravity greater than 1 , which comprises the steps of intimately mixing a hydrophobic, lipophilic absorbent solid material having a specific gravity of less than 1 ,with said solids, permitting said contaminated solids and said absorbent materials to remain in intimate contact for a time sufficient to enable said absorbent material to reach its absorptive capacity, preparing a first suspension of the mixture of said previously contaminated solids and said absorbent materials in a sufficient quantity of water to permit the separation of said first suspension into readily separable layers of absorbent material, aqueous phase and previously contaminated solids and removing said absorbent materials from said suspension.

19. A process of Claim 18 wherein the absorbent material comprises a polymeric substrate in powder, granular or fibre form.

20. A process of Claim 19 wherein the absorbent material comprises a polymer selected from the group consisting of polyethylene, polypropylene and polystyrene.

21. A process for extracting lipophilic contaminants from contaminated solids, said solids having a specific gravity greater than

1 , which comprises the steps of intimately mixing a hydrophobic, lipophilic absorbent solid material having a specific gravity of less than 1 of a polymeric carbohydrate previously treated in accordance with the procedures of claims 1 ,2,3 or 4, with said contaminated solids, permitting said contaminated solids and said absorbent materials to remain in intimate contact for a time sufficient to enable said absorbent material to reach its absorptive capacity, preparing a first suspension of the mixture of said solids and said absorbent material in a sufficient quantity of water to permit the separation of said suspension into readily separable layers of absorbent material, aqueous phase and solids and removing said absorbent materials from said suspension.

SUBSTITUTE SHEET 22. A process of Claim 18 comprising the additional step of adding further quantities of absorbent material into intimate contact with said contaminated solids prior to the first suspension step, until no change in color of the newly added absorbent material is noted.

23. A process of Claim 18 comprising the additional step of adding further quantities of absorbent material after removal of the initially suspended absorbent material from the first suspension step, mixing said further absorbent material with at least said aqueous phase to provide a second suspension, permitting said further absorbent material to form a separable layer and separating said further absorbent material from said second suspension.

24. A process for extracting lipophilic contaminant materials from solids having a specific gravity greater than 1 , which comprises repeating the procedures of claim 23 until no color change is observed in the suspended absorbent material

26. A process of Claims 18, 23 or 24 comprising the additional step of purifying the aqueous phase by contacting it with solid absorbent materials capable of absorbing heavy metal ions and small amounts of lipophilic materials.

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