Abstract: Provided is a recycling method of a polyester cotton blended fabric, including the following steps. A dye-containing polyester cotton blended fabric is put into an acidic aqueous solution containing an oxidizing agent for heating and soaking, so as to degrade the cotton in the polyester cotton blended fabric into powder, and decolorization is performed at the same time to remove the dye. After that, a polyester fabric and cotton powder are obtained by double filtration.

Abstract: A decolorization method of a polyester fabric includes: providing a polyester fabric, in which the polyester fabric is a dyed polyester fabric and the polyester fabric is adhered with a dye and has a first L value; providing a first decolorizing solution and a second decolorizing solution, in which the first decolorizing solution contains a reductant and the second decolorizing solution contains an oxidant; and performing a decolorization process which includes: using one of the first decolorizing solution and the second decolorizing solution to decolorize one portion of the dye and using another one of the first decolorizing solution and the second decolorizing solution to decolorize another portion of the dye, so that a color of the dye is removed and the polyester fabric is white in color and has a second L value that is greater than the first L value.

Abstract: A method for improving the hue of recycled BHET is provided. The method includes: providing a recycled polyester fabric; using a chemical de-polymerization liquid to chemically depolymerize the recycled polyester fabric to form a de-polymerization product; distilling out the chemical de-polymerization liquid from the de-polymerization product by evaporation; dissolving the BHET in water to form a aqueous phase liquid; adding an activated carbon material to the aqueous phase liquid to adsorb impurities; and cooling the aqueous phase liquid to crystallize the BHET from the aqueous phase liquid to obtain a recycled BHET.

Abstract: A method for producing recycled polyester chips from a recycled polyester fabric is provided. The method includes: providing the recycled polyester fabric attached with dyes and/or coating glue; performing a color removal process to at least partially remove the dyes and/or the coating glue attached to the polyester fabric; performing a de-polymerization process which includes: using a chemical de-polymerization liquid to chemically depolymerize the recycled polyester fabric, so as to form a de-polymerization product containing bis(2-hydroxyethyl) terephthalate (BHET) and oligomers; performing a purification process, so as to enhance a purity of the BHET in the de-polymerization product; and performing a granulation process, so as to re-polymerize the purified BHET and form the recycled polyester chips (r-PET).

Abstract: Provided is a recycling method of polyester wool blended fabric, which includes the following. A polyester wool blended fabric containing a dye is put into an acidic aqueous solution containing an oxidizing agent for heating and soaking, so as to degrade a wool in the polyester wool blended fabric, and perform decolorization at the same time to remove the dye. After that, a polyester fabric is obtained by filtration.

Abstract: A method for recycling polyester fabrics with use of an ionic liquid catalyst is provided, which includes: providing a recycled polyester fabric; and using a chemical de-polymerization liquid to chemically de-polymerize the recycled polyester fabric and form a de-polymerization product that includes bis-2-hydroxylethyl terephthalate (BHET). The chemical de-polymerization liquid is used to chemically de-polymerize the recycled polyester fabric in an environment where a de-polymerization catalyst exists, and the de-polymerization catalyst is the ionic liquid catalyst in a solid state.

Abstract: A method for improving hue of recycled bis-2-hydroxylethyl terephthalate by using ionic liquids including providing a recycled polyester fabric; using a chemical de-polymerization liquid to chemically de-polymerize the recycled polyester fabric to form a de-polymerization product; mixing the de-polymerization product with water to form an aqueous phase liquid; dispersing an ionic liquid impurity adsorption material into the aqueous phase liquid to adsorb impurities originally present in the recycled polyester fabric.

Abstract: A decolorization method for a dyed fiber cloth is provided. The decolorization method for the dyed fiber cloth includes steps of: providing a fiber cloth attached with a dye, extracting the dye attached on the fiber cloth by an extractant, and applying a microwave to evaporate the extractant so as to obtain a dried and decolored fiber cloth.

Abstract: A method for preparing a low migration plasticizer of di-2-ethylhexyl phthalate is provided. The method includes a step of adding at least one short chain alcohol component and at least one long chain alcohol component in an esterification reaction between terephthalic acid and 2-ethylhexanol, so as to graft modify a resulting di-2-ethylhexyl phthalate. The esterification reaction is carried out under a temperature from 30° C. to 225° C. and a pressure from 80 mbar to 1033 mbar.

Abstract: A method for manufacturing polyester polyhydric alcohol is provided. The method for manufacturing polyester polyhydric alcohol includes steps as follows. A polybasic acid and a polyhydric alcohol are mixed for oligomerization to form an oligomer mixture. A catalyst is added into the oligomer mixture at a temperature ranging from 190° C. to 210° C. for polycondensation to obtain a polyester polyhydric alcohol product. The polyester polyhydric alcohol product has a number average molecular weight lower than 1000 g/mol and an acid value lower than or equal to 0.3 mg KOH/g.

Abstract: A method for manufacturing polyester polyhydric alcohol is provided. The method for manufacturing the polyester polyhydric alcohol includes steps as follows. A polybasic acid and a first polyhydric alcohol are mixed for a first oligomerization reaction, so as to form a first oligomer mixture. A second polyhydric alcohol is added into the first oligomer mixture for a second oligomerization reaction when a remaining amount of the first polyhydric alcohol in the first oligomer mixture is lower than or equal to 1 mol %, so as to form a second oligomer mixture. A catalyst is added into the second oligomer mixture for a polycondensation reaction, so as to obtain a polyester polyhydric alcohol product. The polyester polyhydric alcohol product has an Alpha value of lower than 30.

Abstract: A plasticizer and a method for producing the same are provided. The method for producing the plasticizer includes: reacting a reaction mixture at each of a plurality of temperature holding stages in a heating process to form a semi-finished product; and purifying the semi-finished product at each of a plurality of low pressure stages of a decompression process to obtain a plasticizer. A temperature range of the heating process is from 140° C. to 220° C., a pressure range of the decompression process is from 750 Torr to 20 Torr, and the reaction mixture contains dibasic acid, diol, monohydric alcohol, and catalyst.

Abstract: A method for purifying by-product ethylene glycol of polyester in converting plasticizer includes: inputting a reaction liquid waste stream including ethylene glycol and 2-ethylhexanol into an ethylene glycol dehydration tower; inputting a hot water stream into the ethylene glycol dehydration tower to mix with the reaction liquid waste stream and to remove the 2-ethylhexanol from the reaction liquid waste stream; dehydrating the ethylene glycol via the ethylene glycol dehydration tower to collect a crude ethylene glycol stream including dehydrated ethylene glycol from a tower bottom of the ethylene glycol dehydration tower and to collect an organic liquid waste stream including the 2-ethylhexanol from a tower top of the ethylene glycol dehydration tower; and inputting the crude ethylene glycol stream into an ethylene glycol distillation tower to collect a ethylene glycol solution from a tower top of the ethylene glycol distillation tower.

Abstract: A method for manufacturing and a method for decolorizing dioctyl terephthalate are provided. The decolorizing dioctyl terephthalate includes: providing an unpurified dioctyl terephthalate; mixing the unpurified dioctyl terephthalate with a reducing agent and an adsorption medium to obtain a first decolorizing product; and mixing the first decolorizing product with a decolorizing adsorbent material to obtain a second decolorizing product. The method for manufacturing dioctyl terephthalate includes: a transesterification step, an alkaline washing and neutralization step, a redox step, a decolorization step and a stripping step; the decolorizing adsorbent material has an acid value between 0.1 and 2 mg KOH/g, a relative humidity between 2 and 10%, and a fineness between 80 and 100 cm2/g.

Abstract: A PVC product and a stabilizing agent thereof are provided. The stabilizing agent is composed of perchlorate, alkanolamine, and alkanolamide. The total amount of alkanolamine and alkanolamide in the stabilizing agent is 80-99 wt % of the total weight of the stabilizing agent, and the weight ratio of the total amount of alkanolamine and alkanolamide to the amount of perchlorate is 4:1 to 99:1, so that the PVC product has a lower Yellowness Index (YI) and higher transparency.

Abstract: A method for manufacturing and a method for decolorizing dioctyl terephthalate are provided. The decolorizing dioctyl terephthalate includes: providing an unpurified dioctyl terephthalate; mixing the unpurified dioctyl terephthalate with a reducing agent and an adsorption medium to obtain a first decolorizing product; and mixing the first decolorizing product with a decolorizing adsorbent material to obtain a second decolorizing product. The method for manufacturing dioctyl terephthalate includes: a transesterification step, an alkaline washing and neutralization step, a redox step, a decolorization step and a stripping step; the decolorizing adsorbent material has an acid value between 0.1 and 2 mg KOH/g, a relative humidity between 2 and 10%, and a fineness between 80 and 100 cm2 /g.

Abstract: A method for purifying by-product ethylene glycol of polyester in converting plasticizer includes: inputting a reaction liquid waste stream including ethylene glycol and 2-ethylhexanol into an ethylene glycol dehydration tower; inputting a hot water stream into the ethylene glycol dehydration tower to mix with the reaction liquid waste stream and to remove the 2-ethylhexanol from the reaction liquid waste stream; dehydrating the ethylene glycol via the ethylene glycol dehydration tower to collect a crude ethylene glycol stream including dehydrated ethylene glycol from a tower bottom of the ethylene glycol dehydration tower and to collect an organic liquid waste stream including the 2-ethylhexanol from a tower top of the ethylene glycol dehydration tower; and inputting the crude ethylene glycol stream into an ethylene glycol distillation tower to collect a ethylene glycol solution from a tower top of the ethylene glycol distillation tower.

Abstract: An eco-friendly polyester molding composition and a method for manufacturing a plastic board are provided. The eco-friendly polyester molding composition includes 50 to 100 PHR of unsaturated polyester resin, 50 to 250 PHR of a filler, 50 to 200 PHR of glass fiber and 0.5 to 10 PHR of at least two initiators. The at least two initiators include a high temperature initiator and a low-to-medium temperature initiator which are mixed in a mass ratio of 0.5-4:1.

Abstract: A method for decolorization of a dyed polyester fiber is provided. The method for decolorization of a dyed polyester fiber includes step of: providing an ether-alcohol solvent and a polyester fiber containing a dye; heating the ether-alcohol solvent up to a boiling point of the ether-alcohol solvent to continuingly generate a fresh gas; wherein a temperature of the fresh gas ranges from 90° C. to 200° C. which is between a glass transition temperature of the polyester fiber and a melting point of the polyester fiber; extracting the dye from the polyester fiber via the fresh gas and forming an extracting condensate containing the dye; reflowing the extracting condensate back into the ether-alcohol solvent; repeating the steps mentioned above to obtain a decolorized polyester fiber.

Abstract: A hydrogenation method for increasing the yield of cyclohexane-1,4-dicarboxylic acid diisooctyl ester is provided. The hydrogenation method uses a hydrogenating reaction tank, which is equipped with a hollow-shaft gas-introducing mixer having air-extracting, air-exhausting and mixing functions, to allow hydrogen gas to be uniformly dispersed in a reaction solution. A ruthenium-on-alumina (Ru/Al2O3) hydrogenation catalyst can be used for carrying out a hydrogenation reaction under gentle conditions. Therefore, the hydrogenation catalyst can be used in a reduced amount, the risk of side reaction(s) can be reduced, and the yield of cyclohexane-1,4-dicarboxylic acid diisooctyl ester can reach at least 99% with a cis isomer proportion of at least 85.0%. The hydrogenation method shows extremely high economic benefit.