61 results about "Glycerol dehydration" patented technology

The invention discloses a heteropolyacid-modified Zr-MOF catalyst which is modified by heteropolyacid through a Zr-MOF carrier. The invention further discloses a preparation method for the catalyst and an application of the catalyst to reaction of preparing acraldehyde by catalyzing glycerol dehydration. Compared with the prior art, the obtained catalyst is long in service life, and the glycerol conversation rate and the acraldehyde selectivity are high; the Zr-MOF carrier is good in thermal stability and chemical stability, and the framework structure is kept stable; theacting force between the heteropolyacid and the Zr-MOF carrier is relatively strong, so that the heteropolyacid-modified Zr-MOF catalyst is not liable to lose.

The invention discloses a preparation method of acrolein, taking biological glycerol as the raw material and the modified zeolite supported heteropolyacid as catalyst, the method prepares acrolein directly by dehydration reaction. 18 to 30 catalyst are put in the middle section of a normal pressure continuous fixed bed reactor, with the volume space velocity of 1 to 10 h<-1>; under the protection of N2, the catalyst bed raises the temperature to 180 to 540 DEG C, and the biological glycerol solvent which is added with inhibitor is put into the fixed bed reactor from a micro pump; after gasified, the glycerine solution reacts by the catalyst bed. After reaction, the product is absorbed by acetone, then is separated and purified, thus obtaining acetone. The invention adopts the alkali metal, phosphoric oxides, alkali metal compound improved catalyst as carrier to carry heteropoly acid catalyst which is green and environmental catalyst and has the advantages of high activity, regeneration property, no pollution, simple reaction, operation process, low production cost, high mole selectivity of acrolein and high conversion rate of biological glycerol.

The invention discloses a preparation method of acrolein, and relates to the field of acrolein preparation by catalyzing dehydration of glycerol. The preparation method is characterized in that: glycerol is used as a raw material, an immobilized ionic liquid is used as a catalyst, and acrolein is prepared by dehydration; the used ionic liquid is acidic ionic liquid [BMIM]BF4 (1-butyl-3-methylimidazolium terafluoroborate) or [BMIM]H2PO4, and the acidic ionic liquid is immobilized by impregnation; the molar selectivity of the acrolein prepared by adding 1-8% of hydroquinone used as a polymerization inhibitor to 10-60% of glycerol aqueous solution used as a reaction solution and reacting under the conditions of atmospheric pressure, reaction temperature of 240-360 DEG C and volume space velocity of 5-15/h can reach 90.4%; and the conversion rate of glycerol can reach 100%. The preparation method has the advantages that the immobilized acidic ionic liquid has higher selectivity in the dehydration reaction of glycerol, the acrolein yield is higher, the reaction stability is good, and the life of the catalyst is long.

The invention discloses a process for preparing acrylic aldehyde by using selective glycerol dehydration and a preparation method of a catalyst thereof. Heteropolyacid/a carrier is disclosed in the expression of the catalyst, wherein the heteropolyacid is one of silicotungstic acid, phosphotungstic acid and phosphomolybdic acid, and the carrier is one of activated aluminium oxide, kieselguhr, activated carbon, rutile type titanium dioxide and kaoline. The catalyst is prepared by using a constant-pore volume dipping method. When the catalyst is used in a fixed-bed miniature reaction device, the transformation rate of glycerol is 13.5%-80.6%, and the selectivity of the acrylic aldehyde is 49.0%-90.5%. When used for carrying out the process for preparing acrylic aldehyde by using glycerol dehydration, the catalyst has the advantages of high catalyst activity, high reaction speed, high selectivity for the acrylic aldehyde and the like, and the main byproduct is hydroxyl acetone.

The invention relates to a method for preparing acrylic acid from propylene, comprising the oxidation of propylene to acrolein and a second step comprising the oxidation of acrolein to acrylic acid, including a glycerol dehydration step preformed in the presence of a gas containing propylene and, more specifically, in the presence of the reaction gas originating from the propylene to acrolein oxidation step. The inventive method enables the use, in part, of renewable raw material, while increasing acrylic acid production.

The invention relates to a method for preparing acrolein from propylene, consisting of a first glycerol dehydration step preformed in the presence of a gas containing propylene and, more specifically, in the presence of the reaction gas originating from the propylene to acrolein oxidation step. The inventive method enables the use, in part, of renewable raw material, while increasing acrolein production.

The invention discloses a method for preparing an acraldehyde catalyst by glycerol dehydration. The method comprises the following steps: firstly, adopting zirconium phosphate as a carrier, selecting one or more of Cu(NO3)2, Fe(NO3)3, Co(NO3)2, (NH4)2Mo2O7, Ce(NO)3 and Ni(NO3)2 as active ingredients, and obtaining an MOx/ZrP catalyst by using an impregnation method; secondly, controlling the reaction temperature at 200 to 400DEG C under the condition of a fixed bed, selecting the MOx/ZrP as the catalyst and 10 to 100 percent of glycerine aqueous solution as a raw material and nitrogen as carrier gas and then carrying out a reaction of preparing acraldehyde by the glycerol dehydration. According to the method disclosed by the invention, the catalyst can be prepared simply and conveniently; better activity still can be maintained after being used for several times; meanwhile, the conversion rate of glycerol is between 80 percent to 100 percent and the selectivity of the acraldehyde is between 50 percent to 100 percent.

The invention discloses a method for prolonging the service life of catalyst in dehydration of glycerol for production of acrolein. Reaction conditions in a fixed-bed reactor are changed for reaction of aqueous solution of glycerol of certain concentration at the low temperature of 240 DEG C and high space velocity of 15h-1, the product acrolein and unreacted glycerol are separated, and thus carbon deposition of the catalyst can be well inhibited and unreacted raw materials can be recycled. By adopting the process, the carbon deposition of the catalyst can be greatly inhibited, so that the catalyst can maintain high activity in a long time. Meanwhile, the problem of low conversion rate of raw materials under the conditions can be solved due to separation of the product, and the process is efficient and environmentally friendly.

The invention relates to a method comprising at least the following steps: a) glycerin is dehydrated so as to obtain a dehydrated product containing acrolein; b) the dehydrated product is subjected to gas phase oxidation so as to obtain a monomer gas containing acrylic acid; c) the monomer gas is contacted with a quenching agent so as to obtain a quench phase containing acrylic acid; d) the quench phase is reprocessed so as to obtain a monomer phase containing acrylic acid. A liquid phase (a1) and a gas phase (a2) are provided during the dehydration process, a plurality of gas bubbles being produced in the liquid phase (a1). The invention further relates to a method for producing polymers by polymerizing acrylic acid, preferably for producing water-absorbing polymers, the water-absorbing polymers obtained by means of said method, a compound, a method for producing a compound, the compound obtained by means of said method, and other chemical products.

The invention belongs to the technical field of chemical industry catalysts, and particularly relates to a nano ZSM-5/gamma-Al2O3 composite catalyst for preparing acraldehyde by glycerol dehydration, and a preparation method and application thereof. In the presence of nano ZSM-5, nano gamma-Al2O3 is prepared by a precipitation process, and the nano ZSM-5 and nano gamma-Al2O3 are uniformly mixed to obtain the composite catalyst with strong interaction. The nano ZSM-5/gamma-Al2O3 composite catalyst solves the problems of poor ZSM-5 stability and low gamma-Al2O3 selectivity in the acraldehyde catalytic reaction by glycerol dehydration. The prepared catalyst has excellent catalytic activity, selectivity and stability in the glycerol dehydration reaction.

The invention belongs to the technical field of chemical catalysts and particularly relates to a multistage pore ZSM-5 catalyst for preparing acrolein by glycerol dehydration and a preparation method of the catalyst. The catalyst comprises a multistage pore ZSM-5 molecular sieve which comprises rich transgranular mesopores; the preparation method comprises the steps that cheap silicon source, aluminium source and organic template reagent are dissolved in water, cavatition of ultrasonic wave and fierce mechanical agitation are used, few small molecular alcohol is added as a cosolvent, and a multistage pore ZSM-5 molecular sieve with MFI structure property is synthesized with a hydrothermal method. The multistage pore ZSM-5 molecular sieve which comprises rich transgranular mesopores is obtained through the cheap preparation technology, the crystal grain is large, the hydrothermal stability is good, and high selectivity and high stability are shown in the acrolein preparation process by glycerol dehydration.

The invention discloses a production method of glycerin tribenzoate. The production method comprises the following steps: carrying out heating reflux for water distribution on glycerol and benzoic acid under the existence of an alkaline substance and a dehydrating agent, carrying out a dehydration esterification reaction, carrying out reaction liquid post-treatment after the reaction is finished, to prepare the glycerin tribenzoate. A ratio of the amount of substance of the glycerol to the benzoic acid is 1: (3.0-3.3); and the alkaline substance is carbonate, bicarbonate, hydroxide or benzoate of alkali metals or alkaline-earth metals. In the invention, a dehydration esterification reaction is carried out under the existence of alkaline, so that side reactions such as glycerol polymerization and glycerol dehydration to generate acraldehyde and the like are greatly inhibited, production of corresponding by-products is reduced, and the yield of the principal product and the content of the product are improved. The operation is simple, the process stability is high, the corrosion and material requirements for equipment are greatly reduced, and meanwhile, the product is low and stable in chromaticity, being suitable for industrial production.

The invention discloses a production technology of 1,3-propylene glycol (PDO) by using a biological fermentation method, belonging to the technical field of biochemical engineering. The production technology comprises the following steps of: preparing 2'-dehydroxylase gene (sisII) from 3',4'-double dehydroxylase gene of sisI in micromonospora inyoensis through genetic recombination, DNA (deoxyribonucleic acid) rearrangement and the like; cloning to obtain sisII; constructing the sisII to a pET30a expression vector, and performing heterologous expression in E.coli BL21 to construct engineering bacteria BL21-sis for synthesizing 1,3-propylene glycol through glycerol dehydration; performing immobilization by a supramolecular self-assembly template method; fermenting to synthesize 1,3-propylene glycol in a glycerol-containing culture medium; and obtaining the product 1,3-propylene glycol through fermentation liquid filtration, organic solvent extraction and the like. The method for preparing 1,3-propylene glycol has the advantages of short production period, simple equipment, environmental friendliness, easiness in operation and control, cheap raw materials and the like, facilitates industrial production and has great practical value.

The invention discloses a method for preparing an acrolein catalyst by dehydrating glycerin. The method comprises the following steps: carrying out acid treatment on a molecular sieve, carrying out alkali treatment, filtering and washing the treated molecular sieve to neutrality, drying the molecular sieve, and carrying out ion exchange and calcining to convert the molecular sieve into a hydrogentype hierarchical porous molecular sieve; and dehydrating glycerin in a fixed bed reaction at a reaction temperature of 280-340 DEG C with the prepared hierarchical porous molecular sieve as the catalyst, a 10-50 wt% aqueous glycerin solution as a raw material and nitrogen as a carrier gas to produce the acrolein. The method has the advantages of simplicity in catalyst preparation and operation,low cost, and the obtained modified molecular sieve material has a high activity, and allows the glycerin conversion rate to be 90-100% and the acrolein selectivity to be 70-85% when applied to the dehydration of glycerin to produce acrolein.

The invention discloses a method for preparing hydroxyacetone by glycerol dehydration. A supported Cr2Cu2O5/SAPO-11 catalyst is used, SAPO-11 is fully used as a carrier, the prepared supported nano copper chromite catalyst is high in activity and good in stability, a pure glycerol feed can be used for replacing glycerol solution feed, the conversion rate of glycerol is 97% or above, and the selectivity of the hydroxyacetone is 95% or above.