304results about "Preparation by alcoholysis" patented technology

The present invention relates to sorbierite cracking process to prepare C2-C4 diatomic alcohol and polyol, and is especially the process of preparing sorbierite with corn material and hydrocracking sorbierite to prepare C2-C4 diatomic alcohol and polyol. The process includes hydrocracking sorbierite to prepare the mixture of C2-C4 diatomic alcohol and polyol at high temperature and high pressure in the presence of cracking sodium hydroxide and nickel/ruthenium catalyst, separation and refining to obtain single product. The production process of the present invention has the advantages of novel production path, unique technological condition, simultaneous production of several kinds of alcohol and high product quality. In addition, using grains, such as corn, as material to replace non-regenerable resource is significant.

A method is provided for co-producing dialkyl carbonate and alkanediol by reacting alkylene carbonate with alkanol in the presence of a IIIA metal oxide catalyst, preferably alumina.

The invention relates to rubber seed oil polyalcohol and a preparation method thereof. The method comprises the following steps of: mixing rubber seed oil, hydrogen peroxide and a catalyst serving as raw materials in a weight ratio of 1:0.5-1.5:0.01-0.05, putting the mixture into a reaction kettle, stirring the mixture and raising temperature to 50 to 80 DEG C, keeping reaction temperature for 3 to 8 hours, lowering the temperature to 30 DEG C, separating acid water out, washing the mixture with aqueous solution of sodium carbonate until the pH of the mixture is between 5 and 6, washing the mixture to be neutral with saturated sodium chloride and water, and performing pressure reduction and water removal at the temperature of between 50 and 90 DEG C for 2 to 5 hours to obtain epoxy rubberseed oil; and adding the epoxy rubber seed oil, methanol, isopropanol and fluoboric acid into the reaction kettle in a weight ratio of 1:1-5:1-5:0.002-0.01, raising the temperature to 75 to 100 DEG C, performing a reaction for 0.5 to 3 hours, washing the reaction product with the aqueous solution of the sodium carbonate until the pH of the reaction product is between 5 and 6, washing the reaction product to be neutral with water, and performing vacuum pumping at the temperature of between 50 and 120 DEG C for 2 to 5 hours to obtain the rubber seed oil polyalcohol. In the method, the conventional petroleum chemical is replaced by a non-edible plant oil resource, so that the dependence of polyurethane industry on petroleum chemicals is reduced, and the added value of the rubber seed oil is increased.

The present invention relates to a continuous process for preparing lower dialkyl carbonates as main product and alkylene glycol as by-product by catalyzed transesterification of a cyclic alkylene carbonate (e.g. ethylene carbonate or propylene carbonate) with lower alcohols, where the reaction of the alkylene carbonate is carried out with an alcohol containing dialkyl carbonate in countercurrent, characterized in that introduction of a stream containing at least 99.5% by weight of alcohol takes place below the point of introduction for the alcohol containing dialkyl carbonate in a particular spacing ratio between the abovementioned points of introduction.

The invention relates to a method for producing epoxy fatty acid methyl ester by using illegal cooking oil, which comprises: subjecting illegal cooking oil and methanol to esterification to obtain fatty acid methyl ester; purifying the fatty acid methyl ester by molecular distillation and performing epoxidation; and subjecting the obtained crude fatty acid methyl ester to three-stage rectification to obtain three models of epoxy fatty acid methyl ester. In the invention, illegal cooking oil is used as a raw material, and esterification is performed under normal pressure; as the reaction temperature is higher than the boiling point of methanol, the methanol is gasified immediately upon contact with fat; and the methanol is uniformly, quickly and fully contacted with the fat, so the esterification speed is further improved. When the method is used, the illegal cooking oil waste is utilized, cost is saved, environment is protected, energy consumption is low, process is simple, operation is safe and product quality is high. Therefore, the method is a resource-saving and environment-friendly production method. The epoxide number of the obtained No.1 epoxy fatty acid methyl ester is 4.0to 5.0, the plasticizing effect of the epoxy fatty acid methyl ester is desirable, the acid value is smaller than 1, the saponification of plasticized products is avoided, a flashing point is above 180 DEG C, an iodine value is smaller than 3, and the epoxy fatty acid methyl ester passed the verification of quality supervision and inspection departments and are approved to be qualified.

An ester-forming monomer obtained by depolymerization of polytrimethylene terephthalate and having an acrolein content of no greater than 0.5 wt %. Polymers obtained using the monomer and fibers, films and molded articles comprising the polymers. The ester-forming monomer is obtained by reacting polytrimethylene terephthalate with at least one compound selected from among monoalcohols, 1,3-propanediol and water in the presence of a basic substance. When the recovered ester-forming monomer is used as the starting material for production of a polymer, it is possible to produce a molding polymer for fibers, films and the like with quality equivalent to or higher than that obtained using virgin monomer.

The invention discloses a method for synthesizing sec-butyl alcohol. In the method, sec-butyl acetate and methyl alcohol are used as raw materials, sec-butyl alcohol is produced by ester exchange, and the by-product is methyl acetate. The yield of sec-butyl alcohol is 50-90%. Compared with the method for preparing sec-butyl alcohol by n-butene hydration, the method is high in reaction speed, high in conversion rate and selectivity, mild in reaction conditions and less in corrosion for equipment; and the by-product methyl acetate is also an important industrial raw material.

The invention relates to a catalytic method for preparing dimethyl cabonate along with ethylene glycol. The invention is characterized in that ethylene oxide and carbon dioxide are used as raw materials to prepare ethylene carbonate under the catalysis of a composite catalyst; the composite catalyst and cyclic carbonate are not separated and are used to further catalyze the reaction of ethylene carbonate and methanol and prepare dimethyl cabonate and ethylene glycol. The synthesis method is characterized by high catalyst activity, low cost, long service life and the like.

The invention relates to a dimethyl carbonate and ethylene glycol production process which is characterized in that the process comprises the following five steps: (a) the carbonylation step for production of ethylene carbonate by catalysis of reaction of ethylene oxide and carbon dioxide by use of an ionic liquid composite catalyst; (b) the step of alcoholysis for ester exchange reaction of the ionic liquid composite catalyst-containing ethylene carbonate solution of the step (a) and methanol in a reaction distillation tower and product separation; (c) the step of purification and refining of dimethyl carbonate from tower top condensate in the reaction distillation tower of the step (b); (d) the step of separation, transformation and refining of ethylene glycol from tower bottom liquid in the reaction distillation tower of the step (b); and (e) the step of circulation cycle of from the ionic liquid composite catalyst in the step (d) to the catalyst in the step (a). The process has the characteristics of high ethylene carbonate one-way conversion rate, simple process flow, small equipment investment, less waste emissions, low energy consumption and the like, and can make companies stronger in competitiveness.

The invention relates to a preparation method of 2-butyl alcohol. The method comprises the following steps: carrying out an ester exchange reaction of 2-butyl acetate and low-carbon alcohol in a catalytic rectifying tower in the presence of an ester exchange catalyst, and collecting the 2-butyl alcohol from tower bottoms, wherein the low-carbon alcohol is C1-C3 alcohol. The method has the advantages of high 2-butyl acetate conversion rate and high 2-butyl alcohol selectivity.

The invention relates to a method for producing polyol by using polyurethane waste. In the scheme adopted by the invention, the method for producing the polyol is characterized by sequentially comprising the following steps of: 1. fully mixing polyurethane waste grains, a polyester polyol alcoholysis agent with molecular weight of 200-2000, and an antioxidant, and then injecting into a reaction kettle; 2. injecting a micro-molecular polyol alcoholysis agent with molecular weight of less than 200 into the reaction kettle, controlling the temperature of the reaction kettle to be between 180 DEGC and 240 DEG C, performing alcoholysis reaction for 30-120 min under the protection of nitrogen; and 3. removing micro-molecular alcohol with molecular weight of less than 200 in vacuum, and reducing temperature and discharging when a hydroxyl value and an acid value reach set values. By adopting the scheme, the invention overcomes the defects of the prior art and provides a preparation method, which is favorable for effectively utilizing resources, reducing or eliminating the source of environment pollution caused by human, and obtaining polyol products with stable quantity.

The invention discloses a method for catalyzing synthesizing sec-butyl alcohol through cation exchange resin. The method comprises the step of carrying out ester exchange under the effect of the cation exchange resin with the sec-butyl acetate and the carbinol serving as the raw materials, so as to synthesize to obtain the sec-butyl alcohol. The sec-butyl acetate provided by the invention has the conversion rate up to 35 to 50%; and the method has the advantages that the reaction condition is mild, the corrosion to equipment is low, the selectivity and the activity of a catalyst are high, and repeated use is realized.

The invention relates to an acid-base two-step process system which comprises a preprocessing system and is used for preparing fatty acid methyl ester and glycerol from kitchen waste oil. The system comprises a kitchen waste oil preprocessing unit, an acid-base two-step esterlysis reaction unit, a glycerol separation and recovery unit, a rinsing and dehydrating unit and a decoloration filtering unit and the like. The processes are as follows: step I: after impurity removal, dehydration and deodorization are carried out on the kitchen waste oil, 40% concentrated sulfuric acid the weight of which is 1-5% of that of the waste oil is added, absolute methanol is added based on the alcohol-oil ratio of (6:1)-(9:1), heating is carried out until the temperature is 60-65 DEG C, the mixture is stirred for 1-3 hours at a revolving speed of 200-400r/min, and then rinsing separation and dehydration are carried out, thus obtaining the fatty acid methyl ester and crude glycerol; and step II: solid base catalyst the mass percent concentration of which is 0.5-5% is added in the rinsed fatty acid methyl ester mixture, absolute methanol is added based on the alcohol-oil ratio of (3:1)-(6:1), reaction is carried out for 1-3 hours at 20-50 DEG C, and then distillation is carried out under reduced pressure, thus obtaining the fatty acid methyl ester.

The invention relates to a method for preparing cyclopentanol from cyclopentene through an indirect hydration method. The method comprises steps that: liquid phase cyclopentene and acetic acid are subject to an addition reaction with a fixed-bed catalyst, such that cyclopentyl acetate is obtained, wherein the catalyst is sulfonic cation exchange resin with a mass exchange capacity of 3-5.5mmol/g;the product of the addition reaction is processed through rectification separation, such that refined cyclopentyl acetate is obtained; the refined cyclopentyl acetate is subject to an ester exchange reaction with methanol under the existence of a catalyst CaO, such that cyclopentanol and methyl acetate are produced; the produced methyl acetate is removed during the reaction process; the product of the ester exchange reaction is filtered, such that the catalyst is removed; and the obtained product is processed through rectification separation, such that the product cyclopentanol is obtained. The method provided by the invention provides substantial positive effects. The addition reaction and the ester exchange reaction have relatively high conversion rate and selectivity, and an average overall yield reaches approximately 80%. More importantly, no substance with high acidity and corrosivity is appeared in the reaction system during the whole reaction process. The raw materials which are not reacted can easily be recovered and reused, and almost no environment pollution is caused.

It is an object of the present invention to provide a specific apparatus and process for industrially producing a high-purity diol by taking a cyclic carbonate and an aliphatic monohydric alcohol as starting materials. Moreover, it is an object to thus provide a specific industrial apparatus and industrial production process that are inexpensive and, for example, enable the high-purity diol to be produced in an amount of not less than 1 ton/hr, preferably not less than 2 tons/hr, more preferably not less than 3 tons/hr, stably for a prolonged period of time (e.g. not less than 1000 hours, preferably not less than 3000 hours, more preferably not less than 5000 hours). According to the present invention, the above objects can be attained by using a continuous multi-stage distillation column A, a continuous multi-stage distillation column C, and a continuous multi-stage distillation column E, which have a specified structure, and withdrawing a liquid component from the side cut outlet, which is installed at the bottom of a chimney tray having a specified structure installed in an enrichment section of the continuous multi-stage distillation column E.

The invention relates to a method for continuously producing dimethyl carbonate and co-producing 1, 2-propylene glycol by virtue of a transesterification method. The method comprises the following steps: (1) reacting and rectifying; (2) recovering dimethyl carbonate; (3) recovering methanol; (4) separating methanol and 1, 2-propylene glycol; (5) carbonizing; (6) filtering; (7) separating 1, 2-propylene glycol; and (8) refining 1, 2-propylene glycol. The method provided by the invention is used for solving the problem in the prior art that 1, 2-propylene glycol is low in yield and low in purity and cannot be continuously produced as a methanol alkaline metal catalyst is hard to be separated from 1, 2-propylene glycol. The purity of 1, 2-propylene glycol produced by the invention reaches 99.99%, so that the pharmaceutical grade production requirement is realized. The method is safe in operating process, energy-saving and high in yield, the discharge of kettle bottom slurry is reduced by 50% or over, and continuous production is realized.

The invention discloses a method for degrading polyethylene terephthalate. The method comprises the following steps: carrying out alcoholysis reaction on the polyethylene terephthalate in the presence of a catalyst by utilizing a brominated 1-butyl-3-ehtyl imidazole ionic liquid and methanol as solvents; and filtering and separating so as to obtain glycol and dimethyl terephthalate, and simultaneously recovering the brominated 1-butyl-3-ehtyl imidazole ionic liquid. By using the method, the characteristic that used high-concentration inorganic strong acid or strong alkaline can not be recycled is overcome, reaction conditions are mild, and the high requirement on equipment is improved.

The invention relates to a methyl ethyl ketone preparation method. The method comprises the following steps: 1, carrying out an ester exchange reaction of sec-butyl acetate and low carbon alcohol in a catalytic rectifying tower in the presence of an ester exchange catalyst, wherein the low carbon alcohol is C1-C3 alcohol; and 2, carrying out a dehydrogenation reaction of the tower bottoms obtained in step 1 or sec-butyl alcohol separated from the tower bottoms obtained in the step 1 in the presence of a dehydrogenation catalyst. The method which allows sec-butyl alcohol to be prepared through using the sec-butyl acetate and the low carbon alcohol has the advantages of high raw material conversion rate and high sec-butyl alcohol selectivity.

The invention relates to the field of production of chemical products, and particularly relates to a preparation method of diethyl carbonate and methylethyl carbonate. The preparation method comprises the following steps: continuously adding the raw materials including dimethyl carbonate, absolute ethyl alcohol and a catalyst into a first rectifying tower for reactive rectification, wherein the temperature of a tower kettle is controlled to be 80-100 DEG C; adding a substance discharged from the tower kettle of the first rectifying tower into a second rectifying tower for reactive rectification to obtain a diethyl carbonate product, wherein the temperature of the tower kettle is controlled to be 115-130 DEG C; adding the substance discharged from the top of the second rectifying tower into a third rectifying tower for reactive rectification to obtain a methylethyl carbonate (EMC) product, wherein the temperature of the tower kettle is controlled to be 100-115 DEG C. The preparation method provided by the invention is used for preparing diethyl carbonate and methylethyl carbonate by adopting a continuous reactive rectification process, and the parameters such as the operation ratio, the reflux ratio and the like of the rectifying tower need not to be changed after being determined during the whole operation process as long as the feeding process is well controlled, therefore, the energy consumption is relatively low.

The invention relates to a method and a system for preparing 3-methyl-2-buten-1-ol through ester exchange. According to the method, solvent-free heterogeneous catalysis ester exchange reaction is carried out on 3-methyl-2-buten-1-ol acetic acid ester and methyl alcohol used as raw materials under the catalytic action of solid alkali or strongly alkaline anion exchange resin so as to obtain 3-methyl-2-buten-1-ol and methyl acetate, and after purification, the unreacted methyl alcohol and the unreacted 3-methyl-2-buten-1-ol acetic acid ester can be recycled. The method has the characteristics that the catalyst is easy to separate, recycle and reuse, no three wastes (waste gas, industrial wastewater and industrial residue) are generated, the yield of the 3-methyl-2-buten-1-ol product is high, and the like.

The invention provides a method for preparing cyclohexanol from cyclohexyl carboxylate serving as raw material by performing an ester exchange reaction under a near critical or supercritical condition. According to the method, a catalyst is not used, reaction products do not need to be separated in the reaction process, and low alcohol-to-ester ratio can be adopted; furthermore, the method has the characteristics of high reaction rate, high conversion rate, high selectivity and simple aftertreatment.