Process for purifying bis(2-hydroxyethyl)terephthalate (BHET) obtained from depolymerization of a polyethylene terephthalate (PET) waste, the process comprising: treating said solution with at least one oxidizing agent at a temperature of from 30° C. to 100° C., preferably from 50° C. to 90° C., to obtain an oxidized solution; treating the oxidized solution with at least one adsorbing agent to obtain a purified oxidized solution; separating the at least one adsorbing agent from the purified oxidized solution to obtain a purified BHET solution. This process is particularly effective for eliminating organic dyes and other low molecular weight organic contaminants, so as to achieve a high purity degree of the recovered BHET.

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.

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.

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.

The invention relates to a method of separation by fractionalization of the antioxidant active ingredients of Rosemary plant, which are the diterpenes Carnosic acid and Camosol and the phenolic acid Rosmarinic Acid, through column chromatography method. The production process involves the passage of rosemary extract, which is obtained in/with a proper solvent, through a column packed with a suitable packing material, the separation of the part rich in carnosic acid and carnosol, and the obtainment of a deodorized product in powder form after drying. During the process, another extract containing rosmarinic acid with high antioxidant activity is also obtained. The invention thus allows the use of an extract rich in carnosic acid and carnosol and another extract containing rosmarinic acid—which are obtained at once with no need for additional processes like acidification, precipitation, membrane filtration or deodorization—in food, pharmaceutical and cosmetic sector applications.

The invention relates to a method of separation by fractionalization of the antioxidant active ingredients of Rosemary plant, which are the diterpenes Carnosic acid and Camosol and the phenolic acid Rosmarinic Acid, through column chromatography method. The production process involves the passage of rosemary extract, which is obtained in/with a proper solvent, through a column packed with a suitable packing material, the separation of the part rich in carnosic acid and carnosol, and the obtainment of a deodorized product in powder form after drying. During the process, another extract containing rosmarinic acid with high antioxidant activity is also obtained. The invention thus allows the use of an extract rich in carnosic acid and carnosol and another extract containing rosmarinic acid—which are obtained at once with no need for additional processes like acidification, precipitation, membrane filtration or deodorization—in food, pharmaceutical and cosmetic sector applications.

The disclosure provides a decolorization and purification method of BHET material, which includes the following steps. A first dose of activated carbon is added to preliminarily treat the BHET material. After the preliminary treatment, a first cooling crystallization process and filtration are performed to obtain BHET crystals. Afterwards, an oxidant is used to chemically react with the BHET crystals to destroy a dye or impurities, and then a second dose of activated carbon is added to adsorb a chemically reacted oxide. Next, a second cooling crystallization process, filtration, and drying are performed to obtain a finished product of BHET.

The disclosure provides a decolorization and purification method of BHET material, which includes the following steps. A first dose of activated carbon is added to preliminarily treat the BHET material. After the preliminary treatment, a first cooling crystallization process and filtration are performed to obtain BHET crystals. Afterwards, an oxidant is used to chemically react with the BHET crystals to destroy a dye or impurities, and then a second dose of activated carbon is added to adsorb a chemically reacted oxide. Next, a second cooling crystallization process, filtration, and drying are performed to obtain a finished product of BHET.

Provided is a chiller and system that may be utilized in a supercritical fluid chromatography method, wherein a non-polar solvent may replace a portion or all of a polar solvent for the purpose of separating or extracting desired sample molecules from a combined sample/solvent stream. The system may reduce the amount of polar solvent necessary for chromatographic separation and/or extraction of desired samples. The system may incorporate a supercritical fluid chiller, a supercritical fluid pressure-equalizing vessel and a supercritical fluid cyclonic separator. The supercritical fluid chiller allows for efficient and consistent pumping of liquid-phase gases employing off-the-shelf HPLC pumps. The pressure equalizing vessel allows the use of off-the-shelf HPLC column cartridges. The system may further incorporate the use of one or more disposable cartridges containing silica gel or other suitable medium. The system may also utilize an open loop cooling circuit using fluids with a positive Joule-Thompson coefficient.

Provided is a chiller and system that may be utilized in a supercritical fluid chromatography method, wherein a non-polar solvent may replace a portion or all of a polar solvent for the purpose of separating or extracting desired sample molecules from a combined sample/solvent stream. The system may reduce the amount of polar solvent necessary for chromatographic separation and/or extraction of desired samples. The system may incorporate a supercritical fluid chiller, a supercritical fluid pressure-equalizing vessel and a supercritical fluid cyclonic separator. The supercritical fluid chiller allows for efficient and consistent pumping of liquid-phase gases employing off-the-shelf HPLC pumps. The pressure equalizing vessel allows the use of off-the-shelf HPLC column cartridges. The system may further incorporate the use of one or more disposable cartridges containing silica gel or other suitable medium. The system may also utilize an open loop cooling circuit using fluids with a positive Joule-Thompson coefficient.