KR0161100B1 - Method of separating and recycling waste polyester magnetic film - Google Patents

Abstract

The present invention relates to a method for separating and recovering components of a waste polyester magnetic film, and more particularly, to a waste polyester magnetic film into a high pressure reactor, and to 20 to 300 parts by weight of alcohol and 0.01 to 10 parts by weight of a catalyst. After the conversion to nitrogen atmosphere, the high pressure reactor was sealed and the reaction temperature was raised to 120 to 300 ° C. while mixing the reactants, and the reaction pressure was adjusted to an equilibrium pressure corresponding to the reaction temperature for 30 minutes to 15 hours. The present invention relates to a method of chemically decomposing polyester, polyurethane resin, and PVC of waste polyester magnetic film by transesterification reaction and pyrolysis reaction, and then separating and recovering them into pure raw materials through various stages of separation operation. .

Through the separation and recovery method of the waste polyester magnetic film as described above, the waste polyester magnetic film which has been incinerated in a considerable amount can be recycled very effectively, and the imposing problems caused by the incineration treatment can be solved.

Description

Separation and Recovery Method of Waste Polyester Magnetic Film

The present invention relates to a method for separating and recovering a waste polyester magnetic film, and more particularly, after the polyester and the polyurethane resin of the waste polyester magnetic film are chemically completely decomposed by a transesterification reaction, they are separated at various stages. The present invention relates to a method for separating and recovering pure raw ingredients through a process.

Recently, the production of polyester magnetic film is increasing due to the surge in demand. In addition, a large amount of defective products are generated during the sheet disc manufacturing process. Large amounts of waste polyester magnetic film have been released during the manufacturing of video, audio cassette tapes and floppy diskettes. The waste polyester magnetic film thus released is an industrial waste, and most of it is incinerated in the related industry. However, waste polyester magnetic film generates air pollutants during incineration, which causes air pollution as well as problems of complete combustion, so the disposal method of waste polyester magnetic film by incineration has a large economic loss to the treatment cost. It is also a big loss in terms of resource recycling. Due to this, the polyester magnetic recording media manufacturing industry has a lot of difficulties in the treatment of the waste polyester magnetic film, and there is an urgent need for an efficient treatment and recycling method thereof.

Japanese Patent Application Laid-Open No. Hei 4-201205 is a representative related patent for recycling waste polyester magnetic film, which incorporates fat oil and carbon black into the waste polyester magnetic film and heats it to melting temperature. After cooling and solidifying it, and then crushing into a fine powder is disclosed, the fine powder prepared as described above can be used as a black pigment discloses a recycling method of the waste polyester magnetic film. However, the black pigment thus prepared has a polyester component of the waste polyester magnetic film, so the amount thereof is very limited because it cannot be applied to compounding with a polymer product which is incompatible with polyester. Moreover, the use of waste polyester magnetic film as a pigment is less economical since the polyester resin or raw materials of polyester resin or polyester resin, ferrite and carbon black are expensive raw materials. There is this.

In order to solve the above disadvantages, in the present invention, the waste polyester magnetic film is chemically completely decomposed and then recovered as pure raw materials through several steps of separation process to extend the recycling range of waste polyester and use it as a pigment. It also added value added and solved the limitation of usage.

It is therefore an object of the present invention to provide a method for separating and recovering waste polyester magnetic film.

The method of the present invention for achieving the above object is to put a waste polyester magnetic film in a high pressure reactor, and then to 20 to 300 parts by weight of alcohol and 0.01 to 10 parts by weight of a catalyst is converted to a nitrogen atmosphere and the high pressure reactor is sealed Then, the reaction temperature was raised to 120 to 300 ° C. while mixing the reactants, and the reaction pressure was adjusted to an equilibrium pressure corresponding to the reaction temperature to be reacted for 30 minutes to 15 hours. The resin and PVC are chemically completely decomposed by a transesterification reaction and a pyrolysis reaction, and then separated and recovered into pure raw materials through a multi-step separation operation.

Hereinafter, the present invention will be described in more detail.

Since the waste polyester magnetic film used in the present invention is a waste produced in the process of bonding ferrite and carbon black to a polyester film using a polyurethane resin and PVC as a binder, the waste polyester magnetic film is a polyester film, ferrite. , Carbon black and traces of polyurethane and PVC. Therefore, in the present invention, the polyurethane resin and PVC used as the polyester film and the binder are selected and reacted to form a reaction type, reaction conditions, and catalysts capable of causing chemical decomposition or pyrolysis reaction at the same time. It is purified in a pure state so that it can be reused as a raw material.

If the polymer materials used in the polyester magnetic tape are not simultaneously degraded to the monomer level, the diacids such as terephthalic acid (hereinafter referred to as TPA), dimethyl terephthalic acid (hereinafter referred to as DMT), diethyl terephthalic acid (hereinafter referred to as DET), etc. It is difficult to recover glycols such as ethylene glycol (EG), propylene glycol (hereinafter PG) and butanediol, and it is difficult to recover polyols from which the polyurethane resin is decomposed and urethanes at the level of monomers decomposed. Since it is difficult to recover the pure ferrite and carbon black, or the mixture of ferrite and carbon black, which is used, in the present invention, polymer materials such as polyester resin, polyurethane resin and PVC are simultaneously decomposed to monomer level in the same reaction system.

In order to decompose the waste polyester magnetic film, the waste polyester magnetic film, water or alcohol, and a catalyst are added to a high pressure reactor equipped with a pressure gauge to depolymerize the polyester film and the polyurethane resin over a certain reaction time at an appropriate temperature. Can be.

At this time, when depolymerization is carried out by adding water, the polyester film and the polyurethane resin are hydrolyzed, and the polyester film is decomposed into glycols such as TPA and EG, and the polyurethane resin is decomposed into diamine, dialcohol and carbon dioxide. Comes out. However, the hydrolysis reaction of the polyester has a higher reaction temperature and reaction pressure than the alcohol decomposition (alcoholyis) reaction, not only the reaction conditions are difficult, but also the reaction time is very long, the hydrolysis reaction of the polyurethane resin proceeds easily, but it is not uniform There is a disadvantage that the resulting products are produced. In other words, decomposition of the polyurethane into polymerization repeating units is not easy. For this reason, the hydrolysis reaction of the waste polyester magnetic film is very difficult to produce a uniform product, and the yield is also very low. In particular, the heterogeneous decomposition reaction makes it difficult to completely separate the ferrite and carbon black attached to the waste polyester magnetic film to the particle level. However, with the appropriate alcohols and catalysts, both polyester and polyurethane resins are completely degraded to the monomer level at the same time. In addition, since PVC is also pyrolyzed by the appropriate reaction temperature and time, not only pure chemical raw materials decomposed from the polymer materials are recovered, but also ferrite and carbon black are completely separated from the polymer materials to facilitate recovery.

For this reason, in the present invention, the waste polyester magnetic film is completely decomposed into monomer units by alcohol decomposition instead of hydrolysis under appropriate catalyst and reaction conditions, and then recovered as reusable raw materials through several steps of purification.

The alcohol used in the alcohol decomposition reaction may be various alcohols such as meth alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, isobutyl alcohol, pentyl alcohol or isopentyl alcohol, and most preferably, methyl alcohol. This is because glycol decomposition, such as DMT and EG, is produced by alcohol decomposition reaction of the pe-polyester magnetic film using methyl alcohol, and these are easily reused as a raw material of the polymerization reaction of polyester and other chemical raw materials.

In addition, the polyurethane used in the bonding of the polyester film and the ferrite is also completely decomposed to the semi-bobbin level of the polyurethane by alcohol decomposition reaction, so that the polyol (mainly diol) used in the synthesis of the polyurethane resin and --OCH at both terminal groups are used. _It is made of urethane at the monomer level having ₃ groups. And since the pyrolysis reaction proceeds at a high temperature of 100 ° C. or higher, PVC decomposes into charcoal and HCl through sufficient reaction time at a high temperature of 100 ° C. or higher. The decomposed charcoal and HCl are traces, and since the charcoal is carbon black or graphite, the charcoal and HCl are recovered together with the carbon black used in the polyester magnetic tape. In addition, HCl can be removed by neutralization during the purification or recovered as HCl.

As described above, the alcohol pyrolysis reaction of the waste polyester magnetic film completely decomposes the polyester film and the polyurethane and PVC used as the binder into monomer-level materials, so that the raw material is uniform and pure when appropriately separated and purified. This allows for full recycling of the waste polyester magnetic film.

The alcohol decomposition reaction of the waste polyester magnetic film and the conditions thereof according to the present invention are as follows, and the following weight parts are based on 100 parts by weight of the waste polyester magnetic film.

A waste polyester magnetic film is added to a high pressure reactor, and 20 to 300 parts by weight of alcohol and 0.01 to 10 parts by weight of catalyst are added thereto, and then converted into a nitrogen atmosphere and the high pressure reactor is sealed. If the economical efficiency is lowered, if it is 20 parts by weight or less, it is difficult to completely decompose. If the catalyst is 10 parts by weight or more, it is not economical. If it is 0.01 parts by weight or less, there is a problem in the complete decomposition reaction of the polyester and polyurethane resin. And the reaction temperature is raised to 120 to 300 ℃ while mixing the reactants by a suitable mechanical operation, if the temperature is higher than the pressure rises more than necessary, the operating conditions are difficult, if it is below the temperature, the reaction does not proceed because the temperature The range is appropriate. The reaction pressure is an equilibrium pressure corresponding to the reaction temperature, and the reaction time is preferably 30 minutes to 15 hours.

The reactant polymerized with the alcohol is separated into a liquid component and a solid component through a method such as filtration or centrifugation. The separated solid component contains charcoal produced by pyrolysis of diacids, ferrites, carbon black and PVC, and the liquid component contains glycols such as EG produced by depolymerization of alcohol and polyester resin as an excess reactant, The products by depolymerization of polyurethane resin and pyrolysis reaction of PVC and a small amount of diacids are dissolved and mixed.

As a method of separating the separated solid components back into their respective components, first, by dissolving the diacids using an organic solvent, the ferrite is separated by magnetic separation, and the remaining solution is filtered or centrifuged. Method is to separate the dissolved diacids and carbon black, and secondly, to selectively dissolve the diacids with an organic solvent and to separate the ferrite and carbon black in a mixture state.

In the magnetic separation method of the ferrite alone separation, the use of an electric magnetic field is effective for separating the ferrite, and the carbon black completely removed from the ferrite is reusable for the polyester magnetic film. However, according to the above magnetic separation method, when ferrite is not completely removed and a small amount is present, or when only ferric acid is dissolved to separate ferrite and carbon black into a mixture, the ferrite and carbon black are mixed. It can be used as a shielding material or conductive filler, or as a black pigment. However, when the ferrite is separated from the carbon black, the added value of the carbon black is further improved. Therefore, the ferrite and carbon black mixtures can be separated by specific gravity method using their specific gravity difference or by using magnetic field separation method such as permanent magnetic field or electric magnetic field. Only ferrite can be selectively separated.

The diacids dissolved in the organic solvent are recovered by distillation. At this time, the decomposed polyurethane component and HCI may be present together, and these components may be removed by washing with an appropriate polar solvent such as methyl alcohol and water and then filtering. A small amount of diacid may be present in the washed polar solvent, which is recovered by adding a polar solvent and insoluble solvent such as water to precipitate the diacid. The remaining material after the separation process is that the polyurethane resin is decomposed, and the urethane, glycol, polyol, and water of the monomer level having --OCH ₃ groups at both end groups are separated and separated by distillation, respectively, so that they are polyurethane and other Can be reused as a chemical raw material.

The diacids dissolved in the organic solvent may be recovered by a recrystallization method in which the temperature is lowered to a certain extent and then the temperature is lowered.

The organic solvents include methyl ethyl ketone, ethyl ether, acetone, ethylene dichloride, carbon tetrachloride, benzene, ethyl acetate, butyl acetate, chloroform, toluene, ethylenediamine or dioxane.

In the liquid component separated from the solid component immediately after depolymerization, glycols such as EG generated by depolymerization of alcohol and polyester resin injected as excess reactants, products by depolymerization of polyurethane resin, HCI produced by pyrolysis reaction of PVC And small amounts of diacids are dissolved and mixed.They are separated by appropriate branching methods, and they are recovered as glycols such as EG and polyurethanes, HCI and diacids at monomer level in which both terminal groups are substituted with --OCH ₃ . Reuse as esters, polyurethanes and other chemical raw materials. There are three methods for the separation. Firstly, it is a mixture of unreacted alcohol produced by depolymerization of alcohol and polyester resin, products of glycol such as EG, and depolymerization of polyurethane resin, in which a small amount of diacids are dissolved in the mixture, which is insoluble with diacids. After distillation and recovery of diacids by adding water as a solvent, HCI, alcohols, diacids, EG and glycols, and monomer-level urethanes having --OCH ₃ groups at both terminal groups are separated. Second, since a small amount of diacid is dissolved in the liquid component, an appropriate amount of distilled unreacted alcohol is distilled off, and then the temperature is lowered to remove the diacid first by recrystallization, and then other components are separated by fractional distillation. Third, firstly remove the monomer-level urethane having --OCH ₃ group at both end groups with activated charcoal, then add diacids and insoluble solvent to precipitate and recover the diacids, and the remaining components are separated by HCI. Alcohols, EGs, other glycols and polyols.

Examples of catalysts that can be used for the transesterification and depolymerization reactions include Lewis acid catalysts such as zinc chloride, iron chloride, aluminum chloride, mercury chloride, carboxylic acids such as acetic acid, formic acid, propionic acid, butyric acid and benzoic acid, and magnesium acetic acid. Inorganic acetates such as calcium acetic acid, zinc acetic acid, sodium acetic acid, phosphoric acetic acid, methylene sulfonic acid, ethylene sulfonic acid, propylene sulfonic acid, butylene sulfonic acid, pentylene sulfonic acid, hexylene sulfonic acid, heptylene sulfonic acid, octylene sulfonic acid and other saturated aliphatic Systemic sulfonic acid, trifluorinated sulfonic acid, trichloride sulfonic acid, p-toluene sulfonic acid, cyclohexane sulfonic acid, benzene sulfonic acid, organic sulfonic acid such as pyrosulfuric acid, methylene sulfinic acid, ethylene sulfinic acid, propylene sulfinic acid , Octylene sulfonic acid and other saturated linear aliphatic solutions Acid and the like, three peulreu ohreuhwa sulfinyl acid, trichloroacetic acid sulfinyl, sulfinyl p- toluenesulfonic acid, a cycloalkyl acid sulfinate, benzene sulfinate, Nick sulfinyl acid as acid.

On the other hand, the separation and recovery method according to the present invention is not only applicable to waste polyester magnetic films alone, but also waste polyester magnetic tapes, waste polyester fibers, and wastes separated from a percopher tape to waste polyester magnetic films. It can be applied with polyester film or waste polyester oligomer sludge.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1

10 g of waste polyester magnetic film, 150 g of ethyl alcohol, and 1.5 g of calcium acetic acid were added to the high pressure reactor, and the inside of the reactor was converted to nitrogen, and the reactor was sealed. And while stirring the reaction, the reaction temperature was raised to 290 ℃ and reacted for 4 hours. After the reaction, the reaction was separated into a liquid component and a solid component through a centrifuge. The separated solid components include diethyl terephthalic acid (DET), ferrite and carbon black, of which DET was dissolved in 2 liters of ethylene dichloride, and ferrite was separated by magnetic fractionation, and then DET was dissolved in a centrifuge. The liquid and carbon black were separated. The separated and recovered ferrite and carbon black were washed with 500 mL of ethylene dichloride and water and dried to prepare pure ferrite and carbon black. And DET dissolved in ethylene dichloride was recovered by distillation. In addition, the liquid component centrifuged after the reaction was slowly heated to evaporate HCI and ethylene until visual confirmation that a significant amount of DET was precipitated, and then DET was recovered by recrystallization of DET at -20 ° C. The liquid recovered from the DET was separated by ethanol, EG, polyol, and monomer-level urethanes having -OCH ₃ groups substituted at both end groups by fractional distillation. Thus, 79.1 g of DET, 19.8 g of EG, 20.5 g of ferrite, 1.6 g of carbon black, 1.7 g of polyol, 1.2 g of monomer-level urethane substituted with dark brown --OCH ₃ groups, and 1.2 g of HCI were recovered, respectively.

Example 2

The reaction was carried out in the same manner as in Example 1, but 80 g of methanol instead of ethyl alcohol and 1.5 g of zinc acetic acid instead of potassium acetic acid were added to the reactor and reacted at a reaction temperature of 210 ° C. for 8 hours. The reaction was centrifuged to separate the liquid and solid components. The separated solid components include dimethyl terephthalic acid (DMT), ferrite and carbon black. Among them, DMT is dissolved in 1 liter of chloroform, and then ferrite is selected and separated by magnetic fractionation. And carbon black were separated. Separated and recovered ferrite and carbon black was washed with 500mL of chloroform each and dried to prepare pure ferrite and carbon black. And DMT dissolved in chloroform was recovered by distillation and washed with methanol or water to remove a very small amount of polyurethane resin, decomposition products and HCI. Methanol used for washing dissolves a small amount of DMT, so water can be added to precipitate DMT, and the ferrite and carbon black can be separated. The separated ferrite and carbon black were sufficiently washed with chloroform, and then ferrite was separated from the ferrite and carbon black mixture by magnetic separation, and chloroform was evaporated to recover carbon black. The DMT was recovered by centrifugation, and the remaining solution was fractionally distilled to separate methanol, water, EG, polyol, and monomer-level urethanes each substituted with --OCH ₃ at both terminal groups. Thus, the monomer level urethane 1.1g and HCI 1.1 substituted with 69.8g of DMT, 20.2g of EG, 21.1g of ferrite, 1.7g of carbon black, 1.3g of polyol, and both terminal groups --OCH _{3 which} are dark brown polyurethane decomposition products. g was recovered.

Example 3

The reaction was carried out in the same manner as in Example 2, but 150 g of methanol and 0.5 g of zinc chloride instead of zinc acetic acid were added to the reactor, and the reaction was carried out at a reaction temperature of 200 ° C. for 12 hours. The reaction was centrifuged to separate the liquid and solid components. DMT in the separated solid component was dissolved in 1 liter of chloroform and centrifuged again to separate DMT, ferrite and carbon black dissolved in chloroform. And DMT dissolved in chloroform was recovered by distilling chloroform. Ferrite and carbon black were washed with chloroform, dried and recovered in a mixed state. In addition, the liquid component separated by centrifugation after the reaction was separated and purified in the same manner as in Example 2 to obtain DMT 68.2g, EG 20.4g, ferrite and carbon black mixture 23.7g, polyol 1.0g, dark brown polyurethane decomposition product. 1.4 g and 1.3 g of HCl were recovered.

Example 4

The ferrite and carbon black mixture prepared in Example 3 was separated by ferrite and carbon black, respectively, to prepare ferrite 22.1 g and carbon black 1.6 g.

Example 5

The reaction was carried out in the same manner as in Example 1, but 150 g of methanol instead of ethyl alcohol and 3.0 g of zinc chloride instead of calcium acetic acid were added to the reactor and reacted at a reaction temperature of 270 ° C. for 10 hours. 73.1 g of dimethyl terephthalic acid, 20.8 g of EG and 1.7 g of carbon black, 1.5 g of polyurethane decomposition product and 1.1 g of HCl were recovered.

Comparative Example 1

The reaction was carried out in the same manner as in Example 1, but 200 g of distilled water instead of ethyl alcohol and 0.2 g of para-toluene sulfonic acid instead of calcium acetic acid were added to the reactor and reacted at a reaction temperature of 120 ° C. for 10 hours. TPA crystals produced after the reaction and solid components such as ferrite and carbon black were separated from unreacted distilled water, EG and other glycol components decomposed from the polyester resin, and components decomposed from the polyurethane resin. Among the solid components separated first, TPA was dissolved in 100 g of dimethyl sulfoxide, which was then separated from the solid components ferrite and carbon black. The separated TPA solution was distilled off the solvent to recover the TPA of the solid component. At this time, the urethane decomposable substance which may be present in the recovered TPA was removed with ethanol to prepare pure TPA, and ferrite and carbon black were separated by magnetic separation to recover pure ferrite and carbon black. The recovered TPA was 5.2g ferrite 1.5g and carbon black 0.4g was very low recovery. In addition, 2.1 g of EG was recovered for the liquid component separated immediately after the reaction using a fractional distillation method.

As in the above embodiment, the chemical components which are decomposed and recovered from the waste polyester, respectively, may be used as a raw material for polymerization of polyester or polyurethane resin as well as other chemical raw materials. The ferrites and carbon blacks recovered in Examples 1, 2 and 4 can be reused for the production of polyester magnetic recording media and other uses, respectively, and the mixture of ferrites and carbon blacks recovered in Example 3 is EMI shielding material, It can be applied to conductive fillers, magnetic materials or mixtures of magnetic materials and can also be used as pigments. Especially when used as a pigment, since the polyester resin is completely removed, it is easily compounded with any polymer product. Therefore, ferrite and carbon black mixed materials can be used as pigments and simultaneously used as EMI shielding materials or conductive fillers, and they can be separated by specific gravity method and magnetic field method, respectively, and then used as polyester magnetic film materials. May be used.

Through the separation and recovery method of the waste polyester magnetic film as described above, the waste polyester magnetic film which has been incinerated in a considerable amount can be recycled very effectively, and the imposing problems caused by the incineration treatment can be solved.

Claims (11)

100 parts by weight of waste polyester magnetic film was added to a high pressure reactor, and 20 to 300 parts by weight of methyl alcohol and one catalyst selected from the group consisting of magnesium acetic acid, calcium acetic acid, zinc acetic acid, sodium acetic acid, phosphoric acid and p-toluene sulfonic acid After adding 0.01 to 10 parts by weight, switching to a nitrogen atmosphere, closing the high pressure reactor, raising the reaction temperature to 120 to 300 ° C. while mixing the reactants, and adjusting the reaction pressure to an equilibrium pressure corresponding to the reaction temperature. Separation of the waste polyester magnetic film, characterized in that the polyester, polyurethane resin and PVC of the waste polyester magnetic film by chemical reaction completely decomposed by the transesterification reaction and the pyrolysis reaction to separate and recover for minutes to 15 hours. And recovery method. The method of claim 1, wherein the waste polyester is a solid component and alcohol, glycols, which is a mixture of DMT, ferrite, carbon black and charcoal through the filtration or centrifugation after the magnetic film is completely decomposed and separated chemically and physically, A method of separating and recovering a waste polyester magnetic film, characterized in that the products obtained by depolymerization of polyurethane resin and pyrolysis reaction of PVC and a small amount of diacids are dissolved into a mixed liquid component. The method of claim 2, wherein the solid component is used for dissolving the diacids using an organic solvent, and then by separating the ferrite by magnetic separation method, the separation of the waste polyester magnetic film, characterized in that the carbon black and Recovery method. The method of claim 2, wherein the solid component is an organic solvent using a solvent to dissolve the diacids separated ferrite and carbon black, characterized in that the separation and recovery of the waste polyester magnetic film. The waste poly according to claim 4, wherein the ferrite and carbon black mixtures are separated by specific gravity fractionation using their specific gravity difference or selectively separated only ferrite using magnetic fractionation such as permanent magnetic field or electric magnetic field. Method for Separation and Recovery of Ester Magnetic Films. The method of claim 3 or 4, wherein the diacids dissolved in the organic solvent are recovered by distilling the organic solvent. The method of claim 6, wherein when the polyurethane component and HCl decomposed during the distillation are present together, washing with an appropriate polar solvent and water and then removing the waste polyester magnetic film by filtration or centrifugation. . The organic solvent according to claim 3 or 4, wherein the organic solvent is methyl ethyl ketone, ethyl ether, acetone, ethylene dichloride, carbon tetrachloride, benzene, ethyl acetate, butyl acetate, chloroform, toluene, ethylenediamine or dioxane. Separation and recovery method of waste polyester magnetic film. According to claim 2, The separation method of the liquid component is a solvent insoluble with diacids, precipitated and recovered by fractional distillation method of HCl, methanol, diacids and insoluble solvents, EG and glycols and monomer levels Separation and recovery method of the waste polyester magnetic film, characterized in that each separated by urethane. The method for separating liquid components according to claim 2, wherein the separation of the liquid components is carried out by distilling an appropriate amount of unreacted methanol, lowering the temperature to remove the diacids first by recrystallization, and then separating the other components by fractional distillation. Method for separating and recovering polyester magnetic film. According to claim 2, The separation method of the liquid component is to selectively remove the monomer-level urethane with activated carbon, and then by distillation and recovery by adding a solvent insoluble with diacids, the remaining components are separated by HCl, methanol, A method for separating and recovering spent polyester magnetic films, characterized in that it is separated by EG, other glycols and polyols.