DE2716797A1 - Regeneration of a polymeric adsorbent - by contacting with a supercritical fluid to remove the adsorbate by dissolution - Google Patents

Abstract

Parent patent describes the removal of organic impurities from water using an adsorbent and sepg. the adsorbate from the adsorbent by bringing the adsorbent contg. adsorbate into contact with a supercritical fluid which is a solvent for the adsorbate, so that the latter is dissolved and removed from the adsorbent. In this addition (a) a polymeric adsorbent (PA) is contacted with a stream of water contg. the organic material (OM) so that the OM is adsorbed by the PA; (b) the PA contg. OM is contacted with a supercritical fluid so that the OM dissolves in the supercritical fluid; (c) the supercritical fluid contg. OM is sepd. from the adsorbent; (d) the supercritical fluid is transformed by a physical treatment into a non-solvent for the OM and a 2-phase system is formed; (e) the non-solvent supercritical fluid phase is sepd. from the OM phase; and (f) the supercritical fluid is reconverted into a solvent for the OM by a physical method. Used to remove impurities e.g. pesticides, insecticides detergents, explosives or biological substances from waste water, coloured matter or from the bleaching waste from a pulp mill. The OM is easily sepd. from the adsorbent by the supercritical fluid without causing any physical or chemical change in the OM. Samples can be therefore be analysed to determine the exact amount of impurities present.

Description

Method and apparatus for regenerating polymeric adsorbents and their use for the treatment of wastewater (addition to P 25 44 116.1] the The invention relates to a method and a device for regenerating polymers Adsorbents (hereinafter referred to as adsorbents) and their use for the treatment of wastewater; it relates in particular to the regeneration of Adsorbents and a method for desorbing adsorbed substances (hereinafter referred to as "adsorbates") of polymeric adsorbents by dissolving the adsorbate in an inert solvent maintained in a supercritical state.

A number of inorganic adsorbents have been around for a long time known and the most common among them are activated carbon, alumina, silicon dioxide and silicates.

Although activated carbon as well as various inorganic adsorbents for many purposes are still widely used, development has continued of synthetic polymeric adsorbents on the use in recent years of adsorbents in large-scale processes to a much broader area of application than it was previously given for activated charcoal. In some cases have polymers Adsorbents replaced activated carbon, silicon dioxide, aluminum oxide and the like. One of Main reasons for the rapidly expanding use of polymeric adsorbents it can be seen that to remove the adsorbate from the polymeric adsorbent liquids are used by some solvent or reaction mechanism can. Since this removal by means of a liquid is normally carried out under ambient conditions is carried out, many of the disadvantages, for example in the Regeneration of activated carbon occur to be eliminated.

For the regeneration of the polymeric adsorbents, an organic Solvents such as methanol or isopropanol can be used. If it is with the adsorbate is a weak acid, can be used for the implementation of the same to remove these, a base can be used; if the adsorbate is is a weak base, an acid can be used as the reactant. In the end can be used for adsorption from an ionic solution water and if If the adsorbate is a volatile material, hot water can be used or steam can be used.

Solvent extraction is by far the most common method for the regeneration of a polymeric adsorbent.

After loading the adsorbate with the adsorbed products up to a suitable organic solvent becomes the breakthrough point through the polymer Adsorbent bed passed to dissolve and extract the adsorbate. The costs for the solvents used for the regeneration of the polymeric adsorbates require that a high percentage of the solution is recovered by means of. About that In addition, many of these solvents whether they are in a large amount or in present in small amounts cannot be disposed of without serious pollution problems appear.

In the recovery and purification of such solvents for the Reuse occurs operating factors that reduce the cost of this recovery increase considerably.

In the case of solvent regeneration, the solvent is used for displacement of water (or any other liquid from which the contaminant is removed is used) from the adsorbate bed. This means that a solvent / water mixture which must be separated in the solvent recovery process. As some of the most common and cheap solvents used for regeneration the polymeric adsorbents are highly effective, form azeotropic mixtures with water, Such azeotropic mixtures must be treated during solvent recovery. For the distillation of a mixture that forms an azeotrope, a column is used, to recover a component and the azeotrope. The azeotrope must then be in a second column introduced either at higher or lower pressures works to recover the other component in a purified form. Every these columns must have a large number of theoretical trays. It is therefore it is clear that this is a serious economic problem, albeit the use of a solvent for the adsorbed materials in regeneration of a polymeric adsorbent does not involve a new technique.

Indeed, the size of the solvent recovery prohibits problems often the use of polymeric resin adsorption, if not the unpurified one Regeneration solvent stream recycled or otherwise in can be used economically in a subsequent process.

Efforts are therefore made to develop a method with the help of which Adsorbates are effectively removed from polymeric adsorbents in sufficient quantities or can be extracted and in which the solvent is more economical Way than has been possible up to now for the return in the cycle (hereinafter referred to as "recycling") can be purified.

The main object of the present invention is therefore to provide an improved Specify processes for the regeneration of polymeric adsorbents. Object of the invention it is also to provide a method of the type described above, which is based on based on the dissolution of adsorbates, which makes it possible in an effective and economical manner Way to recover the solvent used and, if desired, the adsorbate. The aim of the invention is also to provide such a method that is based on a wide range of polymeric adsorbent-adsorbate combinations can be used can. The aim of the invention is finally to provide a method as described above Specify the type in which the inevitable solution does not result in additional medium losses Lead to pollution problems.

Another primary object of the invention is to provide an improved Method and improved device for the purification of waste water by Use of a polymeric adsorbent to remove organic contaminants and an inert solvent in the form of a supercritical fluid for desorbing of adsorbates from the adsorbent to regenerate it.

Further objects, advantages and features of the invention will become apparent from the following Description.

In the process according to the invention, polymeric adsorbents are regenerated by desorption of adsorbates therefrom by dissolving the adsorbates in one chemically inert solvent in the form of a supercritical fluid. The adsorbent is used together with the adsorbate adhering to it with a suitable supercritical Fluid or

Liquid (hereinafter always referred to as "fluid") in contact and then the supercritical fluid containing the dissolved adsorbate subjected to a physical treatment to make it a non-solvent for to make at least part of the adsorbate, thereby making the adsorbate and the supercritical Separate fluid into two phases. Subsequent to the separation of the adsorbate from The supercritical fluid is the supercritical fluid that is considered to be in a non-solvent state can be designated in the present case, subjected to a different physical treatment, to bring it back to the state in which there is a solvent for the adsorbate so that it can be recycled. It can therefore be said that it is before is back in a solvent state upon recycle. The physical Treatments can consist of either the temperature, the pressure or the both of the supercritical fluid changes. As an optional measure, this can Adsorbate can be reacted with a reactant, this being in the supercritical Fluid is dissolved or mixed with it.

In the detailed description below, the term "Non-solvent condition" applied to the supercritical fluid to indicate that there is a relatively low dissolving power for one or more adsorbates and the term "solvent state" refers to the supercritical fluid applied to indicate that there is a relatively high solvency for one or more Has adsorbates. These expressions are therefore to be understood here not in an absolute sense, but in a relative sense.

The invention accordingly encompasses several stages and the relationship between one or more of these stages to each other stage are in the following described method explained in more detail, but the invention by no means is limited. The following detailed description, with reference is carried out on the accompanying drawings, only serves a better Understanding the nature and objects of the present invention. They show: FIG. 1 a graphical representation of naphthalene solubility in carbon dioxide over a range of temperatures from 35 to 550C for selected prints; 6 shows a modification of that in the main patent (Patent application P 25 44 116.1) described device.

The commercially available polymeric adsorbents can be used as hard, insoluble, porous polymers with a large specific surface area will. Usually they are in the form of spheres with a nominal particle size from about 0.99 to about 0.29 mm (16 to 50 mesh). They are available with a wide variety of Polarities and surface properties, which makes it possible to use them as adsorbents to use for a wide variety of purposes. So it can be, for example in the case of polymeric adsorbents, styrene polymers and styrene / divinylbenzene copolymers or polymers which contain acrylic acid esters, trimethylolpropane trimethacrylate or trimethylolpropane dimethacrylate (see e.g. R.M. Simpson, "? he Separation of Organic Chemicals from Mater ", distributed at the third international symposium of the Institute of Advanced Sanitation Research on April 13, 1972, wherein exemplary chemical structures for polymeric adsorbents are given; vg1 also the German Offenlegungsschrift 1 943 807).

The polymeric adsorbents have many different uses found in wastewater treatment. For example, they are used to decolorize the Kraft pulp mill bleaching effluent and dye waste and removal of pesticides from wastewater streams, for the removal of alkylbenzenesulfonate or Linear alkyl sulfonate type surfactants from wastewater and for Removal of explosive substances, such as TNT and DNT, from effluents used. These polymeric adsorbents are also used in analytical methods to determine trace amounts (from down to parts per billion parts (ppb)) of organic contaminants in water, in chemical treatment and in the isolation of enzymes and Proteins and other biological materials such as vitamin B-12, tetracycline, Oxytetracycline and oleandomycin are used.

Examples of pesticides produced by adsorption on a polymeric adsorbent Can be removed from a wastewater stream are lindane, DDT and malathion and Pesticide additives such as endrin, heptachlor and other chlorinated hydrocarbon intermediates.

Examples of organic materials made using polymeric Adsorbents that can be removed from a water stream are such as them in Table I below, given by Junk et al in the "Journal of Chromatography", 99, 745-762 (1974). The resins used were about two different polystotrols with a helium porosity of 42 6 / o or 51%, a specific surface area of 330 m2 / g or 750 m2 / g, an average pore diameter of 90 a or

50 i, basic densities (structural densities) of 1.08 g / cm3 or

1.09 g / cm3 and a nominal particle size of 0.83 to 0.29 mm (20 to 50 mesh) (commercially available under the designations XAD-2 and XAI) -4 from Rohm & Haas Company).

Table I From a stream of water by adsorption on polymeric adsorbents removable organic materials: alcohols hexyl alcohol 2-ethylhexanol 2-octanol Decyl alcohol dodecyl alcohol benzyl alcohol cinnamyl alcohol 2-phenoxyethanol aldehydes and ketones 2,6-dimethyl-4-heptanone 2-undecanone acetophenone benzophenone benzil benzaldehyde Salicylaldehyde Ester benzyl acetate, dimethoxyethyl phthalate, dimethyl phthalate Diethyl phthalate dibutyl phthalate di-2-ethylhexyl phthalate diethyl fumarate dibutyl fumarate Di-2-ethylhexyl fumarate, diethyl malonate, methyl benzoate, methyl decanoate, methyl octanoate Methyl palmitate methyl salicylate methyl methacrylate polynuclear aromatics naphthalene 2-methylnaphthalene 1-methylnaphthalene biphenyl fluorene anthracene acenaphthene tetrahydronaphthalene Alkylbenzenes ethylbenzene cumene p-cymene Acids (acidified) Octanoic acid Decanoic acid palmitic acid oleic acid benzoic acid phenols phenol o-cresol 3,5-xylenol o-chlorophenol p-chlorophenol 2,4,6-trichlorophenol 1-naphthol ether hexyl ether benzyl ether Anisole ether 2-methoxynaphthalene ether phenyl ether halogen compounds benzyl chloride Chlorobenzene iodobenzene o-dichlorobenzene m-dichlorobenzene 1,2,4,5-tetrachlorobenzene a-o-dichlorotoluene m-chlorotoluene 2,4-dichlorotoluene 1 ~ 2,4-trichlorobenzene Nitrogen compounds Hexadecylamine nitrobenzene indole o-nitrotoluene N-methylaniline benzothiazole quinoline Isoquinoline Benzonitrile Benzoxazole As noted above, the polymeric adsorbents regenerated by leaching out the adsorbate, if the adsorbent bed had one beforehand has reached a specified saturation point, which is usually called the break-through point and is defined as the point at which the patient is carried out of bed Stream has a predetermined content of the adsorbate. As already indicated above, this removal of the adsorbate has previously been achieved by Use of an organic liquid solvent such as methanol or isopropanol, under ambient temperature and pressure and involved an expensive solvent recovery process.

According to the process of the invention is used for the regeneration of Adsorbent uses a supercritical fluid, with this method none Phase change of the solvent and thus only a minimal expenditure of energy required is. This process also offers the possibility of the adsorbate in an effective manner regain if so desired.

It is known that when certain gases have a specific pressure exposed and kept above a certain temperature will, they reach a supercritical state.

This supercritical state can be general as used here Senses are defined as the temperature and pressure range above the critical Temperature and the critical pressure of the connection. Although the term ~ supercritical " is generally applied to all temperatures above the critical state, it will be used hereinafter to refer to a gas that has a pressure above its critical pressure and a temperature up to about 1.3 times its critical temperature in 0K. However, in most cases preferably temperatures no greater than about 1.1 times are used the critical temperature in OK, in the process according to the invention has carbon dioxide as particularly suitable for the removal of organic adsorbates from polymers Proven adsorbents. The critical temperature of carbon dioxide is 304.2 ° K (31, 00C) and the critical pressure is 72.9 atmospheres. The temperatures of the most advantageous conditions of use for practicing the invention are between about 1.01 times and 1.1 times the critical temperature or between about 308 and 3350K C34 to 620C), this temperature range is not far above ambient temperature. In addition, carbon dioxide exhibits several others Advantages, including the fact that it does not pollute the atmosphere and it is cheap is.

When choosing a supercritical fluid for regeneration a polymeric adsorbent that contains one or more adsorbed organic materials contains, the supercritical fluid must have a solvent for the materials to be removed and it must be a fluid that does not react with the surface of the adsorbent.

In any adsorbate / supercritical fluid system, the physical Properties to which the supercritical fluid must be subjected in order to make it first to a solvent for the adsorbate and then to a non-solvent for to make the adsorbate, of course, on the solubility of the adsorbate in the supercritical Fluid at different temperatures and pressures. An example of such a thing The system is the naphthalene / supercritical carbon dioxide system.

1 shows the solubility in the form of a graph of naphthalene in carbon dioxide over a temperature range of 35 to 5500 for selected prints (taken from ru.V. Tsekhanskaya, M.B. lomtev and E.V.

Mushkina, "Zh. Fiz. Khim.", 38, 2166 (1964)). This diagram of the Fig. 1 shows that dissolved organic compounds, such as naphthalene, of the supercritical Carbon dioxide solvents can be separated either by: -a) cyclic Change in temperature at constant pressure (e.g.? O at 300 atmospheres, absorb at 5500 and precipitates at 35 ° C "or at 80 atmospheres, absorb at 3500 and Precipitation at 45 ° C); b) cyclic change in pressure at constant temperature (e.g. at 550C, absorb at 300 atmospheres, and precipitate at 80 atmospheres); or c) a combination of cyclic changes in temperature and pressure.

The various embodiments of the method and the device of this invention are shown in somewhat schematic form in Figs Main patent (patent application P 2544 116.1) explained, attached here as Fig. 2-5 are. As an example of the supercritical fluid for removing hydrocarbon contaminants carbon dioxide is used and it goes without saying that a polymeric adsorbent as a replacement for the activated carbon used in the process and in the device according to FIGS. 1 to 4 of the main patent (patent application P 25 44 116.1) is used as an adsorbent. The consumed to be regenerated polymeric adsorbent is in the form of a transportable, finely divided, particulate Material that comes from an adsorbent storage container (val. Fig. 5), and it is through the line 11 substantially at ambient temperature and Ambient pressure in the desorption column 10 (which is used as the fluid contacting device serves), the inflowing spent polymeric adsorbent through the High pressure on-off valve 12 is controlled.

The supercritical fluid for regeneration, e.g. carbon dioxide at a pressure of 300 atmospheres and 350C, is used in the same way as described in the main patent (patent application P 25 44 116.1).

Usually the polymeric adsorbent will not be used before desorption dried as the water is removed by the supercritical carbon dioxide solvent and then by appropriately changing the temperature and / or pressure thereof can be separated. In some cases, however, it may be appropriate to use the remaining To remove water from the adsorbent prior to regeneration with the supercritical fluid. If this is the case, prior to the extraction of the adsorbate from the adsorbent in the contacting column 10, the valves 22 and 24 are closed and the valves 16 and 18 are opened to a drying gas such as hot air over the consumed To conduct adsorbent to remove residual water from it.

Then carbon dioxide flows from the bottom upwards at atmospheric pressure the dried spent adsorbent passed to any in the pores of the used adsorbent to remove remaining air. The valves 16 and 18 are then closed and valves 22 and 24 are opened and the Regeneration is carried out as indicated above.

Then with the valves 12, 22, 23, 16 and 18 closed, the valve 14 is opened and the regenerated polymeric adsorbent is passed through line 13 in the adsorbent storage container 85 transferred, from which it is by means of the pump 86 in the Downstream column 71 can be transferred. The adsorbent regenerated in this way is through line 87 controlled by valve 88 into the column 71 transferred and when the column 70 is out of order, the regenerated adsorbent through line 89 controlled by valve 90, introduced into the same.

Fig. 6 illustrates a modification of that in Fig. 4 of the main patent (Patent application P 25 44 116.1) shown device. In the arrangement according to Fig. 6 omits the separate desorption column 10 together with the line to transferring the used adsorbent into the same and removing the regenerated one Adsorbent from the same. Instead, the desorption takes place directly in the columns 70 and 71, in which case these columns represent vessels that are subjected to pressure can withstand, which is necessary to the supplied from the storage container 20 to keep supercritical fluid in its solvent state. The fluid line 23, through which the supercritical fluid containing the adsorbate alternately from the Columns 70 and 71 is withdrawn, branches into lines 23a and 23b with the valves 24a and 24b, respectively. The fluid line branches out in a corresponding manner 21, through which the supercritical fluid is alternately supplied to the columns 70 and 71 into lines 21a and 21b with valves 22a and 22b, respectively.

The method according to the invention can also be described under Reference to the schematic representation of FIG. 4 according to to the Main patent (patent application P 25 44 116.1) where phenol and 2,4,6-trichlorophenol as adsorbates, a polymeric resin as an adsorbent, and supercritical carbon dioxide can be used as a solvent. An example of such a resin is a polystyrene with a porosity volume of 51%, a true wet density of 1.02 g / cm3, a specific surface area of 780 m² / g, an average pore diameter of 50 i, a basic density (structure density) of 1.08 # com3 and a nominal Particle size from 0.83 to 0.29 mm (20 to 50 mesh). At a water flow rate This polymer absorbs from 1.89 l (0.5 gallons) per minute per 0.028 m3 (ft3) Adsorbent approximately 12.65 kg / m3 (0.78 lbs / ft3) phenol with a 0 ° / loss from a Concentration of 250 ppm in the water feed. This adsorbent adsorbs also contributes up to 194.57 kg / m3 (12 lbs / ft3) of trichlorophenol with a loss of 0 O # the same flow velocity. The regeneration of the adsorbent can be carried out are using supercritical carbon dioxide among those given above Conditions when the breakthrough point in the adsorption is determined. The supercritical Carbon dioxide can be used to remove the phenol and at 350c and 300 atmospheres Trichlorophenol to dissolve out of the polymeric adsorbent, and it can then be in the Non-solvent medium state like the adsorbates can be converted by reducing the pressure decreased to 80 atmospheres and / or increased the temperature to 450C. The presence phenol in the carbon dioxide can be detected by means of an ultraviolet detection device be detected. The reactivated adsorbent obtained in this way can then be used again brought into contact with an additional aqueous phenol / trichlorophenol solution will.

By using a supercritical fluid to dissolve the Adsorbates from its polymeric adsorbent will be Adsorbent none subject to noticeable thermal or chemical degradation and the adsorbed materials can be recovered if desired. In addition, it is possible to do such supercritical fluids, such as carbon dioxide, ethane or ethylene, to use which require the application of temperatures and pressures that are well within the possibilities of the existing devices. These fluids (especially carbon dioxide) are cheap after all, a fact that is essential to economics contributes to large-scale processes and wastewater treatment.

There can be trace amounts of organic contaminants in the wastewater can be detected and amounts down to ppb (parts per billion Divide). After removing contaminants from a stream of water by adsorption on a polymeric adsorbent, they become supercritical Fluid dissolved by the method according to the invention. Because the complete separation the AdsorMat contamination is easily obtained from the supercritical fluid, without causing any chemical or physical change in the adsorbate then known analytical methods for the precise determination of the quantities can be used of the impurities in a given sample can be applied. Blank page

Claims (31)

Claims 1. A method of treating water for removal at least one organic material therefrom using an adsorbent, in which the adsorbent with the adsorbed material adhering to it with a Bringing supercritical fluid into contact, a solvent for the adsorbed material represents, whereby the adsorbed material is dissolved out and deposited from the adsorbent is, according to patent (patent application P 25 44 116.1), thereby g e k e n n z e i c h n e t that a) a polymeric adsorbent with a stream of water, which the contains organic material, under such conditions that the organic material is adsorbed as an adsorbate on the polymeric adsorbent; b) then the polymeric adsorbent with the adhering organic material with a Bringing supercritical fluid into contact, which is a solvent for the organic Material represents whereby the organic material in the supercritical fluid is resolved; c) the supercritical fluid with the organic material dissolved therein separates from the adsorbent; d) the supercritical fluid, which is the organic material contains dissolved therein, subjected to a physical treatment to remove the supercritical To make fluid a non-solvent for the organic material under Formation of a 2-phase system that consists of the supercritical fluid in a non-solvent state and the organic material; e) the resulting 2-phase system in the supercritical fluid in the nonsolvent state and the organic material separates; and f) the supercritical fluid in the non-solvent state after implementation the separation stage is subjected to a physical treatment to turn it into a supercritical one To convert fluid in the solvent state, making it a solvent for the organic material is made. 2. The method according to claim 1, characterized in that as polymeric adsorbent a styrene polymer, a styrene / divinylbenzene copolymer or a polymer which contains an acrylic ester, trimethylolpropane trimethacrylate or trimethylol propane dimethacrylate is used. 3. The method according to claim 1, characterized in that the supercritical fluid used in step (b) a temperature used up to about 1.3 times the critical temperature (in Og) of the fluid. 4. The method according to claim 1, characterized in that as supercritical fluid uses carbon dioxide. 5. The method according to claim 1, characterized in that one in the Step (b) the supercritical fluid at a temperature between about 1.01 and 1.1 times the critical temperature (in OK) of the fluid is used. 6. The method according to claim 1, characterized in that as supercritical fluid carbon dioxide at a temperature between about 34 and about 65 ° C used. 7. The method according to claim 1, characterized in that the physical Treatment of step (d) consists in reducing the pressure of the supercritical fluid reduced. 8. The method according to claim 7, characterized in that the physical Treatment of step (f) consists in keeping the supercritical fluid in the nonsolvent state compressed to a pressure at least equal to its critical pressure. 9. The method according to claim 7, characterized in that the Reduction in pressure caused by expansion caused by a simultaneous Decrease in the temperature of the supercritical fluid is accompanied. 10. The method according to claim 9, characterized in that the physical Treatment of step (f) consists in keeping the supercritical fluid in the nonsolvent state compressed to thereby heat the fluid and its Pressure on to increase a value at least equal to its critical pressure, and that one has an indirect heat exchange between the supercritical fluid in the non-solvent state and the compressed fluid obtained thereby, thereby increasing the temperature of the compressed fluid and the supercritical fluid in the solvent state to convict. 11. The method according to claim 1, characterized in that the physical Treatment in step (d) consists in that the temperature of the supercritical Fluids changes in one direction, and that the physical treatment of the stage (f) consists in having the temperature of the supercritical fluid in the nonsolvent state changes in a direction opposite to that of step (d). 12. The method according to claim 1, characterized in that the physical Treatment of stage (d) and the separation of stage (e) carried out in stages to effect the separation of more than one fraction of the adsorbate. 13. The method according to claim 1, characterized in that the Adsorbate in the supercritical fluid with a reactant for the adsorbate introduced chemically converted. 14. The method according to claim 13, characterized in that the chemical conversion of the adsorbate before the physical treatment of step (d) performs. 15. The method according to claim 13, characterized in that the chemical conversion of the adsorbate after the physical treatment of step (d) performs. 16. The method according to claim 1, characterized in that it is in the case of the water around the bleach effluent from a pulp mill and in the case of the organic one Material is colored bodies. 17. The method according to claim 1, characterized in that it is in the case of water, a stream containing waste dyes as organic matter acts. 18. The method according to claim 1, characterized in that it is the water is a waste water stream that contains pesticides as organic material, Contains insecticides, detergents or explosives. 19. The method according to claim 1, characterized in that the water contains a biological material as the organic material. 20. A method for desorbing an adsorbate from a polymer Adsorbent, characterized in that the polymeric adsorbent is attached to it brings adhering adsorbate into contact with a supercritical fluid that is a solvent represents for the adsorbate, thereby the adsorbate from the polymeric adsorbent leach and extract, taking the temperature of the supercritical fluid within the range between about 1.01 and about 1.3 times the critical Temperature (in ° K) of the fluid. 21. The method according to claim 20, characterized in that as supercritical fluid uses carbon dioxide. 22. The method according to claim 20, characterized in that the supercritical fluid used at a temperature that is within the range between about 1.01 and about 1.1 times the critical temperature (inOK) of the fluid lies. 23. The method according to claim 22, characterized in that as supercritical fluid uses carbon dioxide. 24. A method for treating waste water, in which at least one organic Material is adsorbed on a polymeric adsorbent and the polymeric adsorbent is periodically regenerated by desorption of the organic material from it, thereby characterized in that the polymeric adsorbent is regenerated by the adsorbent with the adhering organic material in contact with a supercritical fluid brings, which is a solvent for the organic material to thereby dissolve the organic material and desorb it from the adsorbent, wherein the temperature of the supercritical fluid has a value that is within the range between about 1.01 and about 1.3 times the critical temperature (in 0K) of the fluid lies. 25. The method according to claim 24, characterized in that as supercritical fluid uses carbon dioxide. 26. Apparatus for treating waste water to remove an organic Materials from it, indicated by the following combination of Features: a) a container means for carrying out the contact between the the waste water containing the organic material and a polymer contained therein Adsorbent, b) a device to the wastewater through the container device in the To lead cycle, whereby the organic material is adsorbed on the adsorbent will; c) a pressure vessel device for carrying out the contact between the Adsorbent with the organic adsorbed thereon Material and one supercritical fluid under temperature and pressure conditions that make the supercritical Maintaining fluid in a solvent state for the organic material, thereby creating the organic material is desorbed from the adsorbent and in the supercritical fluid is recorded; d) a first physical treatment device for the change the physical state of the supercritical fluid, thereby rendering it non-solvent for the organic material to be transferred, creating a 2-phase system from the organic Material and the supercritical fluid is formed in the non-solution state; e) a Fluidleitiingseinrichtung, which the pressure vessel device and the first interconnects physical treatment facilities which are arranged in such a way that that they the supercritical fluid containing the organic material in the first introduces physical treatment device; f) a phase separation device for Separation of the supercritical fluid in the nonsolvent state from the organic Material; and g) a second physical treatment device for transfer the supercritical fluid from the non-solvent state to its solvent state, after which it is returned to the pressure vessel device in the circuit. 27. The device according to claim 26, characterized in that the Container device also serves as a pressure vessel device. 28. The device according to claim 26, characterized in that the first physical treatment means means means for changing the temperature of the supercritical fluid in one direction and that the second physical Treatment device means a device for changing the temperature of the fluid in has a direction opposite to that passed through the first physical treatment facility is effected. 29. The device according to claim 26, characterized in that the first physical treatment device comprises at least two stages, wherein the physical treatment in each subsequent stage is such that the size increases, and that the phase separator has a phase separator which each of the stages of the first physical treatment device follows, whereby the adsorbate can be removed in fractions. 30. The device according to claim 26, characterized in that the the first physical treatment device comprises a fluid expansion device and that the second physical treatment device is a fluid compression device has or consists of it. 31. The device according to claim 30, characterized in that it has a heat transfer device for carrying out a heat exchange between the fluid discharged from the fluid expansion device and the fluid discharged the fluid compression device of carried fluid is suitable.