691 results about "Propionaldehyde" patented technology

The invention relates to a new liquid chain hydrocarbon fuel synthetic route that acquires a platform chemical compound based on a lignocellulose raw material and is completely independent of fossil energy. The liquid fuel obtained by the method can be used as a substitute of aviation kerosene and diesel oil or as an additive for improving the cetane number and cold hardiness of fuels, thereby reducing the national dependence on imported petroleum in terms of liquid fuels. The method provided in the invention consists of two parts: 1) on a novel solid acid catalyst, an aldehyde group-containing compound (such as formaldehyde, acetaldehyde, propionaldehyde, and butyraldehyde, etc.) and a furan platform compound (such as furan, methyl furan, and hydroxylmethyl furan, etc.) undergo an acid catalyzed alkylation reaction to prepare an oxygen-containing organic compound with a carbon chain length of 8-16; and 2) hydrogenation and hydrodeoxygenation are conducted on an alkylation product to hydrogenate unsaturated bonds and remove the oxygen therein, thus preparing aviation kerosene or high grade diesel oil with a carbon chain length ranging from 8 to 16.

The invention discloses a method for preparing methionine. The method for preparing the methionine concretely comprises the steps that cyanohydrins, carbon dioxide and ammonia or sodium cyanide, 3-(Methylthio)propionaldehyde, carbon dioxide and ammonia serve as raw materials to prepare hydantoin; alkaline hydrolysis is conducted on the hydantoin and then the hydantoin is acidized to pH 3.0-6.0 to obtain a compound of the methionine and salts; crystallization is conducted under the condition of temperature ranges from 8 DEG C to 45 DEG C, then the compound is separated to obtain a methionine crystal and salt mother liquor, the methionine crystal is washed by water and dried, and washing liquor is standby; finally, the salt mother liquor is concentrated under the condition of temperature which is lower than 60 DEG C, and then the salt mother liquor passes through a chromatographic column to obtain an inorganic salt and the methionine; the preparation method can efficiently separate the methionine and the salts, the recovery rate of the methionine can reach 99%, and the method is green and protects the environment, no methionine is resolved, no large number of acid and stink wastewater is discharged, and the purity of the inorganic salt is high and can be sold as a commodity.

A cigarette comprises a tobacco rod and a carbon-on-tow filter comprising a fiber tow with flavored or unflavored carbon particles distributed throughout the tow. The carbon particles have high activity in the range of 90 to 115%, preferably 95%. As mainstream smoke is drawn through the filter, gas phase smoke constituents are removed and flavor is released when the particles are flavored. Ventilation is provided to limit the amount of tobacco being combusted during each puff and such ventilation is arranged at a location near the downstream end of the carbon-on-tow filter to lower mainstream smoke velocity through the filter. The filter achieves significant reductions in gas phase constituents of mainstream smoke, including 90% reductions or greater in at least one of 1, 3 butadiene, acrolein, isoprene, propionaldehyde, acrylonitrile, benzene, toluene, and 80% reductions or greater in acetaldehyde over extended shelf life of the cigarettes.

A novel process is provided for producing pramipexole base or its optical isomeric mixture as defined hereinabove i.e. (R,S)-2-amino-6-propyl-4,5,6,7-tetrahydrobenzothiazole avoiding the use of borane tetrahydrofuran complex and using a more convenient reducing agent like sodium triacetoxyborohydride instead. The provided process comprises reacting the starting material (S)-2,6-diamino-4,5,6,7-tetrahydrobenzothiazole or its optical isomeric mixture as defined hereinabove i.e. (R,S)-2,6-diamino-4,5,6,7-tetrahydrobenzothiazole with propionaldehyde in an organic solvent to obtain the respective enamine, which is subsequently reduced in situ, optionally without isolation, to obtain pramipexole or its optical isomeric mixture as defined hereinabove i.e. (R,S)-2-amino-6-propyl-4,5,6,7-tetrahydrobenzothiazole, and the acid addition salts thereof. The present invention also provides a process for purifying pramipexole dihydrochloride or the dihydrochloride salt of its optical isomeric mixture as defined hereinabove i.e. (R,S)-2-amino-6-propyl-4,5,6,7-tetrahydrobenzothiazole dihydrochloride by re-crystallization from a suitable solvent.

The invention provides a method for purifying propylene oxide, and relates to a method for separating methanol, methyl formate and aldehyde in the propylene oxide through extracting and rectifying by continuously operated reactions, wherein, the aldehyde can be formaldehyde, acetaldehyde and propionaldehyde. The method comprises the following steps of: adding an alkaline solution containing ammonia or aminium salt above a feeding point of crude propylene oxide; and a reflux ratio of a condensate liquid selected to return a reactive rectification tower to the purified propylene oxide as a product is between 1 and 5, thereby the content of the methanol in the propylene oxide is less than 600ppm, the content of the methyl formate is less than 100ppm, and the content of the aldehyde is less than 100ppm.

A method for measuring main carbonyl compounds in a main stream smoke of a cigarette through ultra high performance convergence chromatography is a method for measuring butyraldehyde, 2-butanone, propionaldehyde, crotonaldehyde, acrolein, acetone, acetaldehyde and formaldehyde in the main stream smoke. The method is characterized in that a filter leaf processed with a derivatization reagent is used to gather the main carbonyl compounds in the main stream smoke of the cigarette, the analyzing and measuring method is used to obtain the contents of the eight carbonyl compounds in the main stream smoke through ultra high performance convergence chromatography (UPC2). When the method provided by the invention is used to detect the contents of the main carbonyl compounds in the main stream smoke of the cigarette rapidly and effectively, the pretreatment is simple, the average relative standard deviation is less than 7%, and the average recovery rate of various indexes is between 75%-94%. The method has the advantages of rapidness, accuracy, high flexibility and good repeatability.

The invention relates to a method for detecting eight volatile carbonyl compounds in a filter tip through liquid chromatography-tandem mass spectrometry. The eight volatile carbonyl compounds are formaldehyde, acetaldehyde, propanal, acetone, acraldehyde, crotonaldehyde, butanal and 2-butanone. The method comprises the following steps: performing ultrasonic extraction on the carbonyl compounds in a filter tip by using an acetonitrile / water mixed solution, performing 2,4-dinitrophenylhydrazine derivatization reaction, and analyzing through a liquid chromatography-tandem mass spectrometer (LC-MS / MS). Compared with the original gas chromatography, the LC-MS / MS method used in the method has the following advantages: (1) the LC-MS / MS method is higher in sensitivity, and the two-stage mass spectrometry can more effectively eliminate the false positive result, thus ensuring that the qualitative analysis accuracy is higher; (2) separation is performed through liquid chromatography, and 2,4-dinitrophenylhydrazone of the carbonyl compounds has favorable stability; (3) the sample does not need to be purified, and the pretreatment is simple and efficient; and (4) the method can realize the simultaneous detection of the eight volatile carbonyl compounds.

The invention discloses a process method for producing L-2-aminobutanamide hydrochloride serving as an intermediate of levetiracetam, which solves the problem that the conventional produced product has excessively high impurity content or production cost is too high for an enterprise to bear and the like. The method is characterized by comprising the following steps of: reacting propionaldehyde with ammonia water, ammonium chloride and sodium cyanide to obtain 2-amino butyronitrile; hydrolyzing the 2-amino butyronitrile under an alkali condition to obtain 2-aminobutanamide; and splitting the 2-aminobutanamide with L-tartaric acid to obtain the L-2-aminobutanamide hydrochloride. An L-2-amino amides product of which the content is over 99.5 percent is obtained by removing a byproduct, namely, sodium chloride by recrystallization so as to meet the use requirement of foreign customers. The process has the advantages of high yield, high safety and low cost and can be widely suitable for industrialized production of medium-sized and small enterprises.

The invention discloses mixed stewed pork essence which consists of furanone, ethyl maltol, 2-acetylpyrazine, methyl cyclopentenolone, difurfuryl sulfide, 3-sulfydryl-2-butanol, 2-methyl-3-furan mercaptan, di(2-methyl-3-furan mercaptan)-disulfide, methyl(2-methyl-3-furan mercaptan)-disulfide, acetic acid, 3-sulfydryl-2-butanone, 3-propionaldehyde, thiophane-3-acetone, 2,3,5-trimethyl pyrazine, counter,counter-2,4-decadiene aldehyde, furfuryl disulfide, furfurylmercaptan, anise camphor, anisic aldehyde, pepper essential oil, 2-acetyl thiazole, delta-dodecalactone, 4-methyl-5(beta)-hydroxyethyl thiazole acetate, onion oil alcohol, 4-methyl-4-bran sulfenyl-2-pentanone and glycerol triacetate. The mixed stewed pork essence is high in biofidelity and mellow and fine in fragrance, has a good application effect and is economical and practical.

The invention provides a method for 3- hydroxyl propionaldehyde hydrogenation to produce 1,3-propanediol, which comprises using molecular sieve, oxide compound or their mixture as carrier, at the presence of Ni-containing dual-component catalyst, transforming 3-hydroxyl propionic aldehyde aqueous solution into 1,3-propylene glycol through two-stage hydrogenation reaction.

The invention discloses a method for synthesizing (trans)-4-alkyl-3-alkene biphenyl derivative monomer liquid crystals, and belongs to the field of the preparation of monomer liquid crystal materials. The method comprises the following steps of: performing condensation of para-bromo cinnamaldehyde or 3-(4-bromo-phenyl)-propionaldehyde serving as a raw material and alcohol to prepare acetal, and performing a cross-coupling reaction of the acetal and 4-alkylbenzene borate in solvent under the catalytic action of palladium to obtain a biphenyl intermediate; and removing protective group alcohol of the biphenyl intermediate to produce an intermediate, performing a witting reaction of the intermediate and alkyltriphenylphosphonium halide in the presence of potassium tert-butoxide to produce a (cis, trans)-4-alkyl-3-alkene biphenyl derivative, and performing the inversion of cis and trans configuration to obtain the (trans)-4-alkyl-3-alkene biphenyl derivative monomer liquid crystals. The method has the advantages of low cost, high quality of products and mild reaction condition, and the expanded production is easy to perform. Therefore, the method is particularly suitable for the industrial production of the (trans)-4-alkyl-3-alkene biphenyl derivative monomer liquid crystals.

The invention provides a synthesis method of propionaldehyde by low-pressure carbonyl of ethylene, belonging to a preparation method of saturated compound which contains -CHO group and is connected with a noncyclic carbon atom. The synthesis method comprises the steps of: taking ethylene, carbon monoxide and hydrogen as raw materials, adopting a rhodium / phosphonium complex catalyst system, and synthesizing the propionaldehyde by ethylene hydrogen formylation reaction. The synthesis method is characterized by comprising a synthesis operating unit and a rectification operating unit, wherein thesynthesis operating unit comprises a compressor, a synthesis reactor, a coarse propionaldehyde collecting tank and a gas stripping column; an entrainment separator is respectively arranged above the synthesis reactor and the coarse propionaldehyde collecting tank; and an iron-free propionaldehyde solution catalyst system of metal rhodium catalyst and ligand triphenylphosphine is used, the rhodiumconcentration in the catalyst solution is 80ppm-150ppm, and the weight percentage concentration of the triphenylphosphine is 1.5%-3%. The synthesis method of the propionaldehyde by the low-pressure carbonyl of the ethylene is simple in equipment, less in investment, simple in technological operation, and small in catalyst consumption. Counting as the ethylene, the raw material conversion rate is more than or equal to 90%, and the propionaldehyde product content is more than or equal to 99.5%.

The invention discloses a method and equipment for separating propionaldehyde-water-acetic acid mixed liquid by combining azeotropic distillation and extraction distillation by saliferous mixed extracting agent. The steps are as follows: (1) performing azeotropic distillation to propionaldehyde-water-acetic acid mixed liquid, and obtaining about 98 percent of propionaldehyde at the top of an extracting and rectifying tower; (2) extracting and separating the about 98 percent of propionaldehyde by the mixed solvent of saliferous sulfolane and glycerin, obtaining over 99.8 percent of propionaldehyde at the top of the extracting and rectifying tower, and flowing out the saliferous mixed extracting agent from a tower kettle; (3) processing the saliferous mixed extracting agent by a regeneration tower and respectively obtaining 98 percent of propionaldehyde, aqueous solution containing acid and distillate containing the extracting solvent at the top of the regeneration tower; (4) returning 98 percent of propionaldehyde into a material tank of an azeotrope tower for circulation use; and (5) dewatering the aqueous solution containing acid, returning the distillate containing the extracting solvent to a mixed solvent storage tank and circularly using the saliferous mixed extracting agent. The invention has simpler process steps, high product purity, circular utilization of the mixed extracting solvent, no waste liquid emission in the production process and low energy consumption.

The invention provides an olefin purification adsorbent and a method thereof for an olefin purification technology, relating to a method for removing trace of methyl alcohol, dimethyl ether and propionaldehyde from olefin material flow. According to the method, a microballoon adsorbent with certain size distribution is prepared by taking kaolin as an inert matrix, aluminum oxide or inorganic silicon-aluminum mixture as an adhesive, and submicron molecular sieve as an active component; under a gaseous phase or liquid phase working condition, the method is used for removing oxy-compound in olefin material flow by a high pressure low temperature adsorption and low pressure high temperature regeneration technology, so that the contents of components of the oxy-compound in the purified olefin product material flow are less than 1ppm (weight ratio), less ethylene and propylene components are lost, the requirements of the olefin purification technology on low pressure drop and large airspeed liquid phase operation are met, and the method can be used in industrial production.

The invention relates to a method for refining epoxypropane and is mainly used for solving the problems of high cost of an extraction agent and poor quality of a product caused by introduction of an outside-of-system medium existing in the prior art. The method for refining epoxypropane disclosed by the invention comprises the following steps of: by virtue of an extraction agent, extracting the crude epoxypropane solution obtained by reacting hydrogen peroxide ethylbenzene with propylene and containing epoxypropane, water, acetaldehyde, propionaldehyde, methanol, acetone and C3-C7 hydrocarbon impurities and distilling. The problem is well solved by the technical scheme that ethylbenzene is adopted as the extraction agent; the method can be used in the industrial production of refining epoxypropane.

The method for preparing 1,3-propylene glycol by means of hydrogenation of 3-hydroxy-propionaldehyde is characterized by that the weight percentage concentration of raw material 3-hydroxy-propionaldehyde aqueous solution is 10-20%, in the presence of catalyst two-stage hydrogenation process can be adopted to obtain 1,3-propylene glycol, in which the first stage hydrogenation temp. is 25-60 deg.C, second stage hydrogenation temp. is 110-130 deg.C, hydrogen gas pressure of two-stage hydrogenation is 4.0-7.0 MPa, and its space velocity is 0.1-5 hr (-1), and the active component of the catalyst is Ni-A, in which A is any one of Cr, Zn, Mo or Fe, and its carrier is molecular sieve containing Al2O3 or SiO2 or containing both them simultaneously, and the weight percetnage content of the actigve component of the catalyst is 30-60%.

The invention provides a method for synthesizing propyl aldehyde by ethylene hydroformylation. The invention belongs to preparation of a saturated compound which contains a -CHO group which is connected to an acyclic carbon atom. In the method, the ethylene, carbon monoxide and hydrogen are taken as raw materials. The method comprises the following steps: adopting a rhodium phosphine complex catalyst system and ethylene hydroformylating to synthesize propyl aldehyde. The invention is characterized in that the system comprises a synthesis operating unit, a separation recovery operating unit and a rectification operating unit; and in the method, the complete separation of the synthesized propyl aldehyde product from the catalyst is realized; and the method has the advantages of low catalystconcentration, low consumption, low reaction temperature, long service life of the catalyst, high raw material conversion, less impurities in the propyl aldehyde product and high propyl aldehyde content. The synthesized propyl aldehyde product is completely separated from the catalyst, thus avoiding catalyst loss, reducing catalyst consumption, avoiding decomposition of the catalyst and prolonging the service life of the catalyst. A double-synthesis reactor is adopted, raw materials are recycled, feed gas conversion rate counted by ethylene is more than or equal to 95%, and propyl aldehyde content is more than or equal to 99.9%.

The invention belongs to the field of bio-pharmaceutical products, which provides a chemical modification method for recombinate human rh-Endostatin ('rh-ES' is called for short) through the way of using mPEG-propionaldehyde to be combined on the fixed point of free amino of N-terminal amino acid of rh-ES. Mono-PEG-rhES is the output material, its purity meet the requirements of biological products. It plays a key role in the hydrolysis resistance of trypsin and chymotrypsin, it can be used as long-acting formulations for its stability for pH and temperature and there is a great perspective in the clinical treatment of cancer.

The invention relates to a multi-phase catalyst for preparing propionaldehyde by ethene hydroformylation and a fixed bubbling bed reaction technology using the catalyst. More specifically, the multi-phase catalyst is formed by self-loading a transitional metal component by an organic ligand polymer carrier; the organic ligand polymer carrier is formed by polymerizing organic ligand monomers containing P, randomly selected N and alkenyl by a solvent thermal polymerization method and adopts a multistage pore structure; the transitional metal component is one or more of Rh, Ir and Co; furthermore, the content of the transitional metal component is 1-20.0 percent based on the total weight of the catalyst. The preparation method for the catalyst and a reaction technology and a reaction device which apply the catalyst are simple; propionaldehyde prepared by ethene hydroformylation of the catalyst is stable in performance and high in activity and yield; ethene hydroformylation reaction with strong reaction heat is realized; the multi-phase catalyst has wide industrial application prospect.

A reactive rectification column suitable for the production of 2-hydroxy-4-methylmercaptobutyric acid and / or methionine contains a weir having a height of 100 mm or more.

The invention provides a refining method of propylene oxide (PO). The method is a method for refining a crude propylene oxide product prepared through a process for preparing propylene oxide through a CHP (cumene hydroperoxide) method. According to the invention, in a de-heavy tower, C2-C6 alkyldiol is adopted as an extraction agent for removing impurities such as water, propionaldehyde and acetone; bottom liquid enters a solvent recovery tower wherein the extraction agent is recovered, and the extraction agent is circulated and fed from the upper part of the de-heavy tower; in a de-light tower, impurities such as C3-C4 light hydrocarbon and acetaldehyde in de-heavy tower top distillate are removed; de-light tower bottom liquid enters an extraction tower wherein C7-C20 hydrocarbon is adopted as an extraction agent for removing impurities such as residual acetaldehyde and water; extraction tower bottom liquid enters a product tower wherein C7-C20 hydrocarbon is adopted as an extraction agent for removing C5-C6 light hydrocarbon, and a propylene oxide product is obtained at the tower top; and product tower bottom liquid enters a solvent stripping tower wherein the extraction agent C7-C20 hydrocarbon is recovered.

The invention relates to application of anilino lithium, in particular to a method of preparing borate ester based on hydroboration reaction of aldehyde and borane. The method comprises the followingsteps of under the conditions without water and oxygen, in an inert gas atmosphere, adding the borane in a reaction bottle subjected to dehydration and deoxygenation treatment, then adding the anilinolithium as a catalyst, performing uniform mixing, then adding the aldehyde for hydroboration reaction, and performing exposure in the air for reaction termination to obtain the borate ester as a product, wherein the aldehyde is selected from fatty aldehydes. By adopting the method provided by the invention, the condition that the anilino lithium can extremely efficiently catalyze cyclohexanecarboxaldehyde, propionaldehyde and heptanal to generate hydroboration reaction with the borane is discovered for the first time, and a new scheme is provided to prepare the borate ester by adopting a carbonyl compound and the borane to generate the hydroboration reaction.

The invention discloses a preparation method of MHA (2-hydroxy-4-(methylthio) butyric acid). According to the preparation method, nitrile generated by a reaction of a hydrocyanic acid aqueous solution and (methylthio) propionaldehyde is subjected to acidolysis and then treated to obtain an organic phase containing MHA and an aqueous phase containing ammonium salt, the organic phase is subjected to concentrating under reduced pressure and organic solvent treatment or is subjected to direct centrifugal treatment to remove ammonium salt, and MHA is obtained; and the ammonium salt can be further purified to obtain high-purity ammonium salt by-product, and brine waste is not generated. During the preparation process, the used organic solvent can be recycled for application, the used hydrocyanic acid aqueous solution has no tail gas incineration, hydrocyanic acid rectification is not required, and the energy consumption is low; and the organic phase and the aqueous phase are treated separately, compared with direct water removal without phase-splitting, the influence of the ammonium salt on water distillation is reduced, the condition that mass transfer and heat transfer during water distillation are affected by a great amount of ammonium salt is avoided, so that the water distillation quantity is reduced greatly while energy consumption is reduced, and steam is saved.

The invention relates to an epoxypropane purifying method. The problems of high extractant cost and bad product quality due to the introduction of a system outside medium in the prior art are mainly solved. The epoxypropane purifying method is characterized in that a crude epoxypropane solution containing epoxypropane, water, acetaldehyde, propionaldehyde, methanol, acetone and C5C7 hydrocarbon impurities and obtained after a reaction of cumene hydroperoxide and propylene is extracted and distilled by an extractant, wherein the extractant is isopropyl benzene. The epoxypropane purifying method well solves the problems, and can be used in the industrial production of epoxypropane purification.

A process for the production of 2-hydroxy-4-methylmercaptobutyric acid (MHA) by electrochemical carboxylation of 3-methylmercapto-propionaldehyde in an undivided electrolytic cell containing a sacrificial anode, in an aprotic solvent in the presence of a supporting electrolyte. Preferred anode / cathode combinations are Mg / Mg and Mg / carbon. MHA is obtainable in a high yield.

The invention aims at the chemical engineering field, and relates to a method for using crude hydrocyanic acid gas for preparing 2-hydroxy-4-methylmercapto-butyronitrile. Based on the Andrussow method composition principle, the method takes methane, ammonia gas and oxygen gas as raw material to obtain hydrocyanic acid mixed gas I through preparation; the hydrocyanic acid mixed gas I is subjected to deamination treatment to obtain hydrocyanic acid mixed gas II; under the alkaline catalytic action, the hydrocyanic acid mixed gas II is fully reacted with methylmercapto-propionaldehyde to obtain the 2-hydroxy-4-methylmercapto-butyronitrile. The raw material without rectification and purification is adopted for the method and is low in price and easy to get, and the prepared 2-hydroxy-4-methylmercapto-butyronitrile is high in yield and purity. Moreover, an obtained 2-hydroxy-4-methylmercapto-butyronitrilereaction system not purified and separated is stable in property, capable of being stored for a long time and convenient to use in production of down-stream products.

The invention relates to a method for preparing 5-(2-methylmercapto-ethyl)-hydantoin by utilizing crude hydrocyanic acid gas and relates to the field of chemical industry. The method disclosed by the invention comprises the following steps of: completely reacting hydrocyanic acid mixed gas made by adopting an Ann method with methylmercapto propionaldehyde to obtain a 2-hydroxyl-4-methylmercapto-butyronitrile reaction system under the catalytic action of organic alkali; and sufficiently reacting the 2-hydroxyl-4-methylmercapto-butyronitrile reaction system with ammonium bicarbonate in a water medium to obtain 5-(2-methylmercapto-ethyl)-hydantoin. Due to adoption of raw materials which are not rectified or purified, the method disclosed by the invention is short in production time, high in production efficiency and low in production cost; the prepared 2-hydroxyl-4-methylmercapto-butyronitrile reaction system is steady in property and can be stored for a long time; and 5-(2-methylmercapto-ethyl)-hydantoin with high purity and high yield can be obtained through simple separation and purification operations under the synergistic effect of other substances in reaction liquid.