839results about "Preparation by ester-hydroxy reaction" patented technology

The invention relates to a method for purifying a monomer bis (2-hydroxyethyl) terephthalate (BHET) obtained by depolymerizing waste polyester through ethylene glycol (EG), and belongs to the technical field of polyester recycling. The BHET microwave radiation induced film evaporation separation and molecular distillation refining continuous process provided by the invention solves the problems of long process flow, poor continuity, more side reactions and low purity and yield in the direct separation and refining process of BHET in alcoholysis liquid based on a gas-liquid equilibrium separation method at present. The whole technological parameter requirement is mild, the process is short, continuity is good, the BHET purity of the product is larger than or equal to 99.0 wt%, the hue is good, and the BHET yield is larger than or equal to 80.0%. And meanwhile, the method has the advantages that EG is conveniently recycled in a system, the production process is cleaner and more environment-friendly, and the comprehensive efficiency advantage is obvious.

The invention belongs to the technical field of recycled polyester, and particularly relates to a waste polyester textile recycling method which comprises the following steps: decolorizing colored waste polyester textiles by adopting a decolorizing agent which is more than one of dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate; the depolymerization agent is adopted to depolymerize the decolored polyester textile to obtain the terephthalate, and the depolymerization rate of the decolored polyester textile is 98.0-100%; firstly, terephthalate is converted into DMT, and then DMT, ethylene glycol, a catalyst and a functional additive are subjected to a repolymerization reaction to obtain regenerated PET. According to the method, a process of decoloring and depolymerizing sequentially is adopted, and decoloring and depolymerizing are coordinated, so that the process is simplified, the energy consumption and pollution are reduced, and the economical efficiency and sustainability of waste polyester textile recycling are improved.

Disclosed is a method for recycling a polyester blend fabric. The method includes: treating a polyester-containing raw material to be treated, subjecting a resulting treated polyester-containing raw material to polyester degradation at 40° C. to 120° C. for 0.5 h to 8 h in the presence of a catalyst to achieve complete depolymerization, separating out and recovering a polyester component, and reutilizing the polyester component and other blend components.

The invention relates to the technical field of recycling and reusing of solar back plates of photovoltaic modules, and discloses a recycling method of a solar back plate. The recovery method of the solar back panel is characterized by comprising the following steps: (1) in the presence of a protective gas and a catalyst, carrying out alcoholysis reaction on the solar back panel and alcohol to obtain a depolymerized mixed solution; and (2) carrying out purification treatment on the depolymerized mixed solution obtained in the step (1) to obtain bis (2-hydroxyethyl) terephthalate (BHET), polyvinylidene fluoride and polyolefin. According to the method, the PET middle layer in the solar panel can be completely depolymerized into the BHET monomer, the yield is greater than or equal to 78%, and the purity is greater than or equal to 98%; pVDF and PP (or PE) products can be respectively obtained after the PVDF and PP (or PE) materials which do not participate in depolymerization are separated and purified; the whole chemical recovery process is simple in operation method and high in efficiency, and has good economic benefits.

The invention discloses an efficient purification method of rBHET, and belongs to the technical field of waste polyester recycling. A reaction raw material obtained after premixing of waste PET polyester raw material particles and a catalyst and ethylene glycol are jointly and continuously introduced into a depolymerization reactor, the reaction raw material and ethylene glycol in the depolymerization reactor are mixed and pass through a plurality of rotating discs, and the materials form a flowing film on the rotating discs rotating at a high speed to promote depolymerization; depolymerization reaction liquid generated in the depolymerization reactor enters a temporary storage tank to be stored after being subjected to impurity removal, the depolymerization reaction liquid in the storage tank is introduced into a rectifying tower to be primarily concentrated and purified, obtained concentrated liquid enters an evaporator to be secondarily concentrated and purified, obtained secondary concentrated liquid enters a cooler to be cooled and then enters a product tank to be crystallized; and drying the crystallized solid to obtain a high-purity rBHET product. According to the method, the production efficiency is improved, and the purity of rBHET is effectively improved.

The polyester resin according to the present invention is high purity and contains recycled bis(2-hydroxyethyl) terephthalate containing a controlled amount of diethylene glycol ester below a certain level, and therefore has heat resistance and quality comparable to that of the original resin, despite being a polyester resin regenerated by chemical recycling. In particular, the polyester fiber containing the polyester resin according to the present invention has excellent strength, elongation, and processability, and can therefore be used as an environmentally friendly textile product.

The recycled bis(4-hydroxybutyl) terephthalate according to one embodiment has a low amount of residual ethylene glycol derivatives and can therefore be used as a polymerization raw material for high crystallinity engineering polyester products or biodegradable polyesters, offering superior qualities, for example, color.

The invention provides a method for alcoholysis of polyethylene glycol terephthalate, and relates to the technical field of PET degradation. The PET alcoholysis method provided by the invention comprises the following steps: mixing PET, ethylene glycol, a cosolvent and a composite catalyst, and carrying out alcoholysis reaction to obtain bis (hydroxyethyl) terephthalate (BHET). According to the invention, dimethyl sulfoxide is taken as a cosolvent, zinc acetate and 1, 8-diazabicyclo [5.4. 0] undec-7-ene are taken as a composite catalyst, catalysis and solvent effect driving are combined, and ethylene glycol alcoholysis of PET is carried out under the synergistic effect of the composite catalyst and the cosolvent. According to the method, effective decomposition of PET can be achieved at the low temperature (140-155 DEG C) and within the short reaction time (60-100 min), and the yield of BHET is high (66% or above and can reach 80% or above). The method provided by the invention can realize high-efficiency alcoholysis of PET with ethylene glycol.

The invention discloses a process for preparing DMT and DOTP by recycling waste printing and dyeing white mud. The process comprises a pretreatment unit, a methyl esterification unit, a rectification unit, a pulping unit, an ester exchange unit and a refining unit, waste printing and dyeing white mud is used for methyl esterification to prepare DMT, DMT rectification and purification, DMT transesterification to prepare DOTP and DOTP purification. According to the process, efficient esterification of the white mud and product separation can be achieved through the catalyst and the process conditions adopted in the methyl esterification stage, the obtained refined DMT can serve as a polyester monomer product and can also serve as a raw material to further react with isooctanol to prepare DOTP, and high-valued conversion and resource utilization of the white mud are achieved through the process.

The invention discloses a method for efficiently depolymerizing polyethylene glycol terephthalate, which comprises the following steps: mixing a PET material, ethylene glycol and a core-shell type magnetic nano composite catalyst, and carrying out alcoholysis reaction at 160-200 DEG C for 30-180 minutes; after the reaction is finished, separating the catalyst from a reaction system through an external magnetic field to obtain a solution containing bis (2-hydroxyethyl) terephthalate; the core-shell type magnetic nano composite catalyst comprises a magnetic FeO core, a SiO shell layer and active metal sites, the FeO core is coated with the SiO shell layer, the SiO shell layer is an insulating inorganic layer and is of a porous structure, the active metal sites are fixed to the surface of the SiO shell layer through coordinate bonds, and active metal is selected from one or more of Co, Ni, Cu, Ce, La and Al. The problems that an existing PET alcoholysis catalyst is easy to dissolve out, difficult to separate, harsh in reaction condition and poor in cycling stability are solved.

The invention belongs to the technical field of copolymerization modification of degradable polyester, and relates to a depolymerization method and application of polybutylene terephthalate. During depolymerization, polybutylene terephthalate, dimethyl carbonate and dihydric alcohol are mixed and then subjected to a depolymerization reaction, and an intermediate ester is prepared; the dihydric alcohol is dihydric alcohol which does not form a ring with dimethyl carbonate in the depolymerization reaction process; the molar weight of the dimethyl carbonate is 10-30% of the molar weight of a repetitive unit of the polybutylene terephthalate; the sum of the molar weight of a 1, 4-butanediol unit in the polybutylene terephthalate and the molar weight of the added dihydric alcohol is a, the sum of the molar weight of a terephthalic acid unit in the polybutylene terephthalate and the molar weight of the added dimethyl carbonate is b, and the ratio of b to a is (1.2-1.5): 1; during application, the prepared intermediate ester is subjected to transesterification under the condition of negative pressure to obtain the copolyester. The depolymerization method is simple and easy to implement; the depolymerization product can be directly applied.

A polymerization raw material obtained by the depolymerization of waste polyester is disclosed. The polymerization raw material contains recycled bis(2-hydroxyethyl) terephthalate in which the contents of acetate-based ester compounds and diethylene glycol ester compounds are adjusted to specific levels. The polymerization raw material is excellent in purity and quality, and free from the problem that thermal resistance characteristics deteriorate in the polymerization of a polymer from the recycled monomer.

The invention relates to the technical field of recycling of waste textiles, in particular to a method for accelerating degradation of waste polyester, which comprises the following steps: S1, adding crushed polyester materials into organic alcohol, and then adding organic alkali and a photodegradation catalyst to obtain a degradation system; and S2, carrying out a degradation reaction in the degradation system under illumination and heating conditions, and after the reaction is finished, carrying out constant-temperature solid-liquid separation, cooling crystallization, washing and drying to obtain the terephthalic acid glycol ester. The photodegradation catalyst is at least one of nano ZnO and nano TiO2. According to the method disclosed by the invention, low-temperature and rapid degradation can be realized to obtain the terephthalic acid glycol ester, the energy consumption of polyester degradation is effectively reduced, the yield of polyester recovery is improved, and the recycling of polyester fabrics is realized.

The application belongs to the technical field of regenerated polyester, and particularly relates to a recycling method of waste polyester textiles, which comprises the following steps: decolorizing colored waste polyester textiles by using a decolorizing agent, wherein the decolorizing agent is one or more of dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate; depolymerizing the decolorized polyester textiles by using a depolymerizing agent to obtain terephthalate, wherein the depolymerization rate of the decolorized polyester textiles is 98.0-100%; converting the terephthalate into DMT first, and then performing a re-polymerization reaction on the DMT, ethylene glycol, a catalyst and a functional additive to obtain regenerated PET. The application adopts a process of decolorizing first and then depolymerizing, and the decolorizing and depolymerizing are coordinated, so that the process is simplified, the energy consumption and pollution are reduced, and the economy and sustainability of the recycling of waste polyester textiles are improved.

The present invention relates to a process for depolymerizing a polyester feedstock comprising opaque PET, which comprises: a) a conditioning step; b) a step of glycolysis, operated at between 180 and 400° C., a residence time of from 0.1 to 10 h in the presence of diol; c) a diol separation step, at a temperature of between 100 and 250° C., a pressure lower than that of step b) and producing a diol effluent and an effluent rich in monomers; d) a step of separating into a heavy impurities effluent and a prepurified monomers effluent, at a temperature of less than 250° C. and a pressure of less than 0.001 MPa and a residence time of less than 10 min; e) a step of decolourizing the prepurified monomers effluent, by adsorption of a mixture comprising between 20% and 90% by weight of the prepurified monomers effluent and a solvent, at a temperature of between 100 and 200° C., a pressure of between 0.1 and 1.0 MPa and in the presence of at least one adsorbent.

Provided are industrial processes for producing an organic acid alky ester from a feedstock containing organic acids and / or saponifiables, comprising: countercurrently contacting a feedstock with an organic alkylating reagent over two or more vessels or stages at temperature between 100° C. and 400° C. and pressure between 0.1 barg and 355 barg while simultaneously removing water and / or glycerin with unreacted alkylating reagent from the final vessel or stage to result in a first reaction method product containing organic acid alkyl esters, followed by a choice of using the alkyl esters as-is, purifying the organic acid alkyl esters from the first reaction product mixture or subjecting the first reaction product mixture to an additional transesterification reaction to convert saponifiables into additional organic acid alkyl esters, then purifying the organic acid alkyl esters from this second reaction method product.

The invention discloses a method for degrading and recycling waste plastics based on a deep eutectic solvent, and belongs to the technical field of waste plastic resource recycling. The method comprises the following steps: treating waste PET plastic by using a decolorizing agent, carrying out catalytic alcoholysis on the waste PET plastic and ethylene glycol at 180-200 DEG C under normal pressure by using a choline chloride / ethylene glycol / zinc acetate ternary eutectic solvent as a catalyst and a solvent to generate a bis (2-hydroxyethyl) terephthalate monomer, and synthesizing the waterborne polyurethane with isophorone diisocyanate. The preparation method comprises the following steps: mixing waterborne polyurethane with an acrylamide-acrylic acid copolymer and a ternary eutectic solvent, and carrying out UV photopolymerization to prepare the dual-network eutectic gel. The method has the characteristics that the ternary eutectic solvent and Zn < 2 + > synergistically catalyze the degradation of the waste PET to obtain the bis (2-hydroxyethyl) terephthalate monomer with the purity of more than or equal to 96.1% and the yield of more than or equal to 95.3%, and then the eutectic gel with the tensile strength of more than or equal to 1.5 MPa is prepared through photopolymerization, and the temperature is reduced by 60-80 DEG C compared with that of the traditional process. The method effectively solves the problems of high energy consumption, more waste acid and low yield of the traditional waste PET plastic recovery technology.

The present invention relates to a process for preparing bis-(2-hydroxyethyl) terephthalate by depolymerization of a plastic filler comprising PET, comprising: a) a step of depolymerization of the PET in the presence of a diol, so as to have a weight ratio between the diol and the PET of the plastic filler of between 0.3 and 8.0, said step a) comprising a reaction phase operated between 150 and 300°C, b) a step of evaporation of the BHET to produce a BHET-rich stream and a heavy impurity stream, step b) using an evaporator comprising an evaporation zone and a zone for withdrawing the heavy impurity stream, and a section for discharging the heavy impurity stream located downstream of the evaporator, the evaporator being operated at a pressure less than or equal to 0.0010 MPa,and in which the evaporation zone is operated between 120 and 300°C and the heavy impurity stream withdrawal zone and the heavy impurity stream discharge section at a temperature greater than 250°C and less than or equal to 300°C.,

To provide an efficient method for recycling waste PET raw materials by depolymerizing and repolymerizing them.SOLUTION: In a preferred embodiment, waste PET raw material is decomposed by passing nitrogen or the like at a gas hourly space velocity in the presence of a polar aprotic solvent such as methanol and potassium carbonate (K2CO3) to obtain DMT (dimethyl terephthalate). Furthermore, potassium carbonate (K2CO3) and the like are used to manufacture (bis-(2-hydroxyethyl) terephthalate, BHET) and the like.SELECTED DRAWING: Figure 1

The invention provides a photocuring composition and application thereof. The composition comprises the following components: (a) at least one benzoyl formate compound; (b) at least one ethylenically unsaturated photopolymerizable compound; the benzoyl formate compound is obtained by reacting a compound shown in a general formula (I) with a compound shown in a general formula (II) or a general formula (III), or is obtained by further reacting the compounds shown in the general formula (I), the general formula (II) and the general formula (III) with a compound with an end-capped substituent group for end capping. The sensitivity of the obtained product is not reduced compared with that of existing small molecules, and the hardness of the product is improved under LED curing.

The invention discloses a preparation method of an alcoholysis catalyst and application of the alcoholysis catalyst in regenerated DMT synthesis. Zinc, nickel and cobalt metal sources are synchronously loaded on a two-dimensional MXene material through an impregnation method, and then through hydrothermal treatment, calcination and carbon nitrogen compound encapsulation treatment, the self-assembled heterogeneous nitrogen-doped MXene-zinc / nickel / cobalt NC catalyst is prepared and used for ethylene glycol alcoholysis reaction of waste polyester textiles. The method comprises the following steps: carrying out ester exchange reaction on an alcoholysis product obtained by carrying out alcoholysis on the waste polyester textiles by using ethylene glycol and methanol to prepare impurity-containing regenerated DMT, and purifying the regenerated DMT through a reduced pressure sublimation method by utilizing the phase change characteristic of DMT crystals, thereby realizing the preparation of the high-purity regenerated DMT. The heterogeneous alcoholysis catalyst prepared by the method is high in catalytic activity, small in pollution, simple to prepare and easy to separate and recover, meanwhile, the purification process of the ester exchange product DMT is simplified, and the energy consumption and the cost are reduced.

Bis(glycol) terephthalate is prepared by transesterification of bis(2-hydroxyethyl) terephthalate, which is a recycled monomer obtained by depolymerization of a waste polyester, and a glycol having at least 3 carbon atoms, and then is copolymerized, and thus can increase the amount of recycled monomers in a polyester resin, and has improved purity through the removal of impurities during transesterification, thereby enhancing final resin quality such as color.

The invention discloses a zinc oxide modified silicon dioxide catalyst, a preparation method and application of the zinc oxide modified silicon dioxide catalyst in catalytic alcoholysis of waste PET (polyethylene terephthalate), zinc acetate and silicon dioxide are added into a mixed solution of water and ethanol and uniformly mixed, and a mixed reaction solution is obtained; adding a sodium hydroxide aqueous solution into the mixed reaction solution, carrying out a first reaction, and standing to obtain a suspension; and adding an L-ascorbic acid aqueous solution into the suspension, carrying out a second reaction, carrying out solid-liquid separation, and calcining the solid part in an air atmosphere to obtain the product. The prepared zinc oxide modified silicon dioxide nano material can be used as a catalyst to be applied to alcoholysis recovery of waste polyester, the product yield reaches up to 92% or above, the product selectivity is high, metal residues are avoided, the catalyst is easy to recover and can be recycled, and the application prospect is wide.

The invention discloses a preparation method of multi-stimulus-response degradable thermosetting resin containing ketene ester groups, and the method comprises the following steps: carrying out thermocuring cross-linking reaction on a compound containing multifunctional acetoacetate and polyaldehyde to generate the degradable thermosetting resin. The multi-stimulus-response degradable thermosetting resin prepared by the method has excellent creep resistance and can be kept stable under long-time exposure at 120 DEG C. The multi-stimulus-response degradable thermosetting resin and the composite material prepared by using the thermosetting resin as the matrix bring a major breakthrough to the composite material industry, so that the multi-stimulus-response degradable thermosetting resin and the composite material are more suitable for application in extreme environments such as high temperature and high pressure; the application range of the material is expanded, and more innovation and development opportunities are expected to be brought to related fields.

The invention belongs to the technical field of biological medicines, and particularly relates to a royal jelly acid derivative and a synthesis method, a pharmaceutical composition and application thereof. The royal jelly acid derivative is a compound shown as a formula (I), or an enantiomer, a diastereoisomer and a tautomer thereof, or a solvate or a pharmaceutically acceptable salt thereof. A series of royal jelly acid derivatives with novel structures are constructed by using a natural component royal jelly acid derived from royal jelly as an initial raw material, the royal jelly acid derivatives can play a role in resisting pulmonary fibrosis by inhibiting the activity of fibroblasts, the effect of the royal jelly acid derivatives is equivalent to that of pirfenidone, and the royal jelly acid derivatives are expected to be developed into candidate drugs for resisting pulmonary fibrosis. The ceramide NP has excellent effects in anti-inflammatory, anti-allergic and itching-relieving aspects, has a better effect than known ceramide NP, and can be used for preparing health care products, cosmetics and medicines. And # imgabs0 #.

The invention relates to the field of functional materials, in particular to chemical recycling of a series of polyesters represented by PET (Polyethylene Terephthalate) by using a novel and efficient magnesium-based catalyst technology, which is of great significance for treating plastic pollution and realizing green circular economy.

The invention provides an ester exchange reaction separation coupling device and method, and belongs to the technical field of chemical engineering, the ester exchange reaction separation coupling device comprises a reaction kettle, a circulation pipeline and a catalyst preparation tank; the top of the reaction kettle is provided with a feed port, and the bottom is provided with a discharge port; the circulating pipeline is located on the outer side of the reaction kettle, and the two ends of the circulating pipeline are communicated with the feeding port and the discharging port respectively; the circulating pipeline is sequentially connected with a membrane filtering unit, a micro-interface strengthening mixer and a pre-reactor from the discharging opening to the feeding opening, and the circulating pipeline is further connected with a circulating pump; the catalyst preparation tank is connected to the position, between the membrane filtration unit and the micro-interface strengthening mixer, of the circulation pipeline through a feeding pipe; the circulating pipeline is provided with a waste catalyst discharging pipe at the upstream of the feeding pipe, and when part of the waste catalyst in the circulating pipeline is regularly discharged, a new catalyst is supplemented to the circulating pipeline at the same time; according to the arrangement, after mixed feed liquid is introduced into the reaction kettle, the influence of discharge of a waste catalyst on the transesterification reaction in the reaction kettle can be reduced.

The invention discloses a preparation method of a foam Zn (at) ZIF-8 material and application of the foam Zn (at) ZIF-8 material in PET degradation, the Zn (at) ZIF-8 material is prepared and synthesized through a hydrothermal method, foam zinc serves as a substrate, and due to the fact that the foam zinc has the high-strength metal characteristic and a stable three-dimensional network structure, the foam zinc has the high-strength metal characteristic and the stable three-dimensional network structure; then ZIF-8 is introduced to fill gaps, so that the catalyst has ultrahigh porosity and a stable bimetal and multi-active-center-site mutual synergistic structure, the activity of a reactant ethylene glycol is improved, meanwhile, collection and distribution of the reactant and a product are accelerated, the catalytic efficiency is improved, and the product purity is improved; meanwhile, due to the fact that ultrahigh pores of the catalyst have very strong adsorption performance, the whiteness of the product BHET can be greatly improved; and the catalyst has excellent cyclic utilization performance, and keeps the original catalytic activity after being recycled for multiple times.

The present invention relates to a method for alcoholysis of a plastic, in which the plastic is subjected to an alcoholysis reaction using a specific binuclear metal complex catalyst in the presence of an alcoholysis agent to obtain a monomer, and the plastic is one or more selected from the group consisting of polyester, polycarbonate, polyamide and polyurethane. According to the alcoholysis method of the plastic, catalytic alcoholysis can be efficiently carried out, the purity of a monomer product is high, post-treatment is simple, and various plastics can be treated.

The invention discloses a method for recovering monohydroxyethyl terephthalate from a polyester textile, which comprises the following steps: carrying out multi-stage decolorizing treatment on the polyester textile to be recovered by using ethylene glycol as a decolorizing agent to obtain the decolorized polyester textile; mixing a depolymerization catalyst, a sodium phosphate buffer solution and the decolored polyester textile, and carrying out a depolymerization reaction to obtain a depolymerization solution; adding ethyl acetate into the depolymerization liquid for extraction, rotary evaporation concentration and sublimation treatment to obtain monohydroxyethyl terephthalate. According to the method for recycling the monohydroxyethyl terephthalate from the polyester textile, the decolorization rate of the polyester textile can reach 90% or above, the purity of the recycled monohydroxyethyl terephthalate is larger than 98%, and the whiteness of the recycled monohydroxyethyl terephthalate is larger than 97%. The method for recycling the monohydroxyethyl terephthalate from the polyester textile, provided by the invention, is an efficient, economical and green new method for recycling the polyester, and the recycling of the polyester textile is realized.