The method of producing styrene
(57) Abstract:The invention relates to the petrochemical industry and can be used to obtain propylene oxide (OP) and styrene. Describes a method of producing styrene by dehydration methylphenylcarbinol raw materials in the liquid phase, and as a catalyst for the use of phosphoric and/or organic acid, modified additives oxygen and/or nitrogen-containing compounds. Possible dehydration in the presence of hydrogen. The technical result is an increase in the yield of styrene and reduction of the yield of heavy products. The invention relates to the petrochemical industry and can be used to obtain propylene oxide (OP) and styrene.A known method of producing styrene by dehydration of methylphenylcarbinol (IFC) in the presence 0,008-0,15 hours, preferably between 0.01 and 0.1 PM of concentrated sulfuric acid at 100 hours IFC at 110-200oC, preferably 130-180oC, at 500 mm Hg - 2 kg/cm2or normal pressure. The dehydration reaction is recommended in the apparatus, which formed during the reaction water can be removed (application of Japan 62-164637, MKI C 07 C 15/46, publ. 21.07.87 the heavy products and the use of concentrated sulfuric acid, causing severe corrosion of the equipment.The closest in technical essence is a method of producing styrene liquid-phase dehydration of methylphenylcarbinol (IFC) at 180-220oC in the presence of organic sulfonic acids as catalysts (Japan's bid N 62-37021, MKI C 07 C 15/46, publ. 10.08.87, N 3-926, Tokka, Coho).The disadvantages of this method are the low yield of styrene and a significant release of heavy products.The objective of the invention is to increase the yield of styrene and reduction of the yield of heavy products.To solve this problem is proposed a method of producing styrene by dehydration methylphenylcarbinol raw materials in the liquid phase in the presence of a catalyst, which is used as phosphate and/or organic acid, modified additives oxygen and/or nitrogen-containing compounds. Possible dehydration in the presence of hydrogen.As organic oxygen-containing and/or nitrogen-containing compounds are used, such as, for example, ketone, alcohol, carboxylic acid, allenglish, ethers, esters and polyesters derived from olefin oxides and IFC, the organic acid is mouths, the basis of manniche, oksihinolina, alkyldiethanolamine, hydrazine, pyridine, amides, such as formamide, alkylborane, dialkylphosphate, ndimethylacetamide, sulphonamide, amigorena acid, urea and/or mixtures thereof.The use of this method allows to increase the output of styrene, reduce the formation of heavy products and thereby reduce the amount of waste production. The method is as follows. Fraction IFC, consisting of IFC, acetophenone (ACP) and heavy products, is heated to a temperature of 140-200oC, is mixed with a catalyst of liquid-phase dehydration and enters the reactor. As a catalyst for the reaction of liquid-phase dehydration uses a catalyst based on phosphoric and/or organic sulfonic acids, modified additives oxygen and/or nitrogen-containing compounds. Oxygen-containing and nitrogen-containing modifying additives may be introduced into the reactor device or separately and/or together with the acid in the form of pre-prepared solution. The catalyst is introduced into the mixture to dehydration in the amount of 0.001-0.2 wt.% in the calculation of acid. In the reactor at a pressure of 100-790 mm RT. senior flows through the reaction of dehydration of the IFC with the formation of styrene. the at) IFC consisting of styrene, IFC, ACF, heavy food, water and minor amounts of other impurities from the reactor arrive at the separation in the system of distillation columns for the extraction of commodity styrene.All of the above is illustrated by the following examples.Example 1
The process is carried out according to the proposed method. IFC containing of 99.5 wt. % main product and 0.5 wt.% Act, the number 89,5 kg/h is mixed with a catalyst, is heated to a temperature of 180oC and fed into the reactor. The process of dehydration is carried out at a temperature of 180oC and a pressure of 200 mm RT. Art. as a catalyst is used naphthalenesulfonate, modified by amidon sulfuric acid and IFC. The content of catalyst in the reaction mass based on naphthalenesulfonate of 0.01 wt.%.The amount of reaction products from the reactor after separation of the reaction water 77,58 kg/h composition, wt.%: styrene - 88,76; IFC - 4,25; ACF - 6,25; heavy products of 0.62 and other impurities - 0,12. When this conversion IFC was 96,3% and the selectivity of the formation of styrene was 94.2 mol.%. The yield of heavy products laid out on the IFC to 0.72 wt.%.Example 2
The process is carried out on the proposed method,other impurities - 0.8 in number 89,5 kg/h as a catalyst using a complex catalyst consisting of paratoluenesulfonyl, diethylhydroxylamine, Nonylphenol and urea taken in a weight ratio of 1: 0,01:1:0,01. The content of the catalyst is 0.05 wt.% per acid. Paratoluenesulfonyl, diethylhydroxylamine and Nonylphenol injected into the reactor in the form of a solution in a fraction of the IFC. Urea is introduced into the reactor in the form of aqueous solution. Fraction IFC before entering into the reactor is heated to a temperature of 190oC. the Amount of the reaction products from the reactor after separation of the reaction water 79 kg/h composition, wt.%: styrene - 78,82, IFC - 1,64, ACF - 18,82, heavy products - 0.42 and other impurities down to 0.3. During this conversion, IFC 98,3% and the selectivity of the formation of styrene to 94.8 mol.%.Example 3
The process is carried out according to the method described in example 1. In used as the raw material fraction IFC composition, wt.%: IFC - 65, ACF - 34,1, heavy products and other impurities - 0.9 in the number 89,5 kg/h Dehydration IFC in styrene is carried out in liquid phase at a temperature of 200oC, at atmospheric pressure and in the presence as catalyst of phosphoric acid, taken in an amount of 0.1 wt.% per IFC. Phosphoric acid mod is. During this conversion, the Corporation has accounted for 95.8% with a selectivity of formation of styrene of 92.7%. The content of heavy products of 0.91 wt.%.Example 4
The process is carried out under the conditions of example 1. As catalyst, a mixture of equal amounts of phosphate and paratoluenesulfonyl, modified by the addition of diethylamine. The amount of catalyst of liquid-phase dehydration of the per acid is 0.05 wt.% from the supplied IFC.When this conversion IFC was 96,3% with a selectivity of formation of styrene to 92.4%. The content of heavy products to 1.0 wt.%.Example 5
The process is carried out under the conditions of example 1, but the dehydration is carried out in the presence of hydrogen, taken in an amount 0,0006:1 mol/mol per IFC. When this conversion IFC amounted to 97.1% with a selectivity of formation of styrene to 96.8 mol.%. The content of heavy products - 0.56 wt.%.Example 6
The experience is conducted according to the recipe of example 2. As the sulfonic acids used 2,5-(HO)(SO3H)C6H3COOH2H2O (sulfosalicylic acid), taken in an amount of 0.2 wt.%, modified by addition of Mannich bases, taken in an amount of 0.05 wt. % and 0.0005 wt.% diethanolamine. Conversion of IFC was 90,6% selectionfailure use a mixture of ortho - and para-phenolsulfonate, taken in a weight ratio of 1:1 in an amount of 0.2 wt.%, modified additive oksihinolina, taken in an amount of 0.02 wt.% and 0.5 wt.% a mixture of simple and complex esters derived from olefin oxides and IFC. The mixture of simple and complex esters derived from olefin oxides and IFC contains 10 wt.% benzoate of propylene glycol, 15 wt. % benzoate IFC and the rest in equal amounts of dipropyleneglycol, simple ester of the IFC and monopropellants and simple ether IFC. Conversion of IFC amounted to 91.5% at a selectivity of formation of styrene to 96.2 mol.%.Example 8
The experience is conducted according to the recipe of example 2. As sulfonic acids using phenol-2,4-disulfonate, taken in an amount of 0.2 wt.%, modified by addition of stearic acid, taken in an amount of 0.04 wt.% and 0.02 wt.% pyridine. The reaction temperature of the dehydration 130oC. Conversion of IFC was 92.3% with a selectivity of formation of styrene 94,1 mol.%.Example 9
The experience is conducted according to the recipe of example 2. As sulfonic acids, a mixture consisting of 20 wt.% 1-naphthol-2 - and 35 wt.% 1-naphthol-4 sulphonic acids, and 18 wt. % 2-naphthol-3,6 - and 27 wt.% 2-naphthol-6,8-disulfonate, taken in an amount of 0.18 wt.% per monosulphite, modificy the FC amounted to 94.5% with a selectivity of formation of styrene to 96.2 mol.%.Example 10
The experience is conducted according to the recipe of example 2. As sulfonic acids using 1-naphthol 2,4,7-trisulfonic, taken in an amount of 0.2 wt.%, and 3.7-disulfonato 1,2,4,5,6,8-hexoxyethanol, taken in an amount of 0.01 wt. % modified additives of monopropellants, taken in an amount of 0.8 wt. % and 0.05 wt.% hydrazine. Conversion of IFC was 90.8% with a selectivity of formation of styrene 97 9 mol.%.Example 11
The experience is conducted according to the recipe of example 2. As sulfonic acids, a mixture containing a weight ratio of 1:1:1 meta - para - and ortho-sulfobenzoic acid, taken in an amount of 0.2 wt.%. As an additive to the catalyst used ortho-sulphonamide benzoic acid in the amount of 0.03 wt. % of supplied raw materials. Conversion of IFC reached 90.7% with a selectivity of formation of styrene of 97.8 mol.%.Example 12
The experience is conducted according to the recipe of example 2. As sulfonic acids, a mixture of econsultancy with a 1.8-disulfonato anthracene (in a weight ratio of 2:1), taken in an amount of 0.2 wt.%. As an additive to the catalyst used sulfinic benzoic acid and dimethylformamide, taken in a weight ratio of 1:1 in the amount of 0.08 wt.% on the supplied raw material. Conversion of M the inventory example 2. As the sulfonic acids used benzosulfimide, taken in an amount of 0.2 wt.%. As an additive to the catalyst used ndimethylacetamide, in the amount of 0.08 wt.%, and tetraethylene glycol, in an amount of 0.2 wt.%, on the supplied raw material. Conversion of IFC amounted to 93.1% of when the selectivity of formation of styrene 98,7 mol.%.As can be seen from the presented examples, the proposed method allows to obtain styrene with high selectivity and good conversion methylphenylcarbinol. The method of producing styrene by dehydration methylphenylcarbinol raw materials in the liquid phase in the presence of an acid catalyst, wherein the catalyst used phosphoric and/or organic acid, modified additives oxygen and/or nitrogen-containing compounds.
FIELD: industrial organic synthesis.
SUBSTANCE: embodiments of invention are accomplished via liquid-phase dehydration of methyl phenyl carbinol-containing feedstock in presence of acid-type catalyst in column-type reactor-rectifier comprising still portion, built-in heat-exchanger, and rectification portion, volume of still portion constituting 80% of built-in heat-exchanger volume. Temperature of till portion of reactor-rectifier is 140-205°C and temperature in rectification portion 130-180°C. Advantageously, methyl phenyl carbinol-containing feedstock is supplied to and/or under built-in heat-exchanger and catalyst or mixture of catalyst with feedstock and/or still product is supplied to still portion at mixing. Linear velocity of reaction mass vapors within free cross-section of reactor is 0.05 to 0.9 m/s, residence time of styrene in reaction zone 0.05 to 50 sec, and residence time of still product in reactor 5 to 500 h.
EFFECT: increased conversion of feedstock and final product formation selectivity.
5 cl, 14 ex
FIELD: industrial organic synthesis.
SUBSTANCE: invention relates to production of alkylaryl hydroperoxides useful as starting material in production of propylene oxide and alkenylaryl. Process of invention comprises following stages: oxidation of alkylaryl compound to form reaction product containing alkylaryl hydroperoxide; contacting at least part of reaction product with basic aqueous solution; separation of hydrocarbon phase containing alkylaryl hydroperoxide from aqueous phase; containing at least part of above hydrocarbon phase with aqueous solution containing waste water, said aqueous solution containing less than 0.2% alkali metal and/or salt (determined as ratio of metal component to total amount of solution); and separation of hydrocarbon phase from aqueous phase. By bringing at least part of above hydrocarbon phase containing alkylaryl hydroperoxide into interaction with propylene and catalyst, alkylaryl hydroxide and propylene oxide are obtained. At least part of propylene oxide is then separated from alkylaryl hydroxide. Dehydration of at least part of alkylaryl hydroxide results in formation of alkenylaryl.
EFFECT: reduced amount of contaminating by-products in alkylaryl hydroperoxide preparation stage.
8 cl, 4 ex
FIELD: industrial organic synthesis and catalysts.
SUBSTANCE: invention provides a method for processing methanol into dimethyl ether and liquid hydrocarbons, the latter being used as high-octane components of gasolines Ai-92, 95. Processing comprises contacting of raw material, in at least one step, in at least one reactor containing catalyst: Pentasil-type zeolite and binder, followed by cooling resulting products, condensation and separation thereof to isolate methanol conversion hydrocarbon gases, water, and desired products, after which cooled hydrocarbon gases are recycled to methanol conversion stage in at least one reactor. Catalyst is characterized by SiO2/Al2O3 molar ratio 20-100, content of sodium oxide not higher than 0.2%, and additionally contained silicon dioxide and zirconium dioxide at following proportions of components: 1.0-15.0% silicon dioxide, 1.0-5.0% zirconium dioxide, 20-70% zeolite, and binder - the balance.
EFFECT: increased yield of desired products and improved performance characteristics of catalyst.
4 cl, 5 tbl, 18 ex
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to a method for synthesis of styrene. At the first step the method involves interaction of ethylbenzene hydroperoxide with propene in the presence of catalyst to yield propylene oxide and 1-phenylethanol followed by separate treatment of reaction flow and removing propylene oxide. At the second step the method involves interaction of 1-phenylethanol-containing distillate with a heterogenous dehydration catalyst at temperature 150-320°C to obtain styrene. Distillate contains 0.30 wt.-%, not above, compounds of molecular mass at least 195 Da. Invention provides decreasing the content of by-side compounds in styrene and to enhance it's the conversion degree.
EFFECT: improved method of synthesis.
3 cl, 3 tbl
FIELD: chemical industry; methods of production of the pure isobutene out of the isobutene-containing mixture.
SUBSTANCE: the invention is pertaining to the method of production of the pure isobutene out of the isobutene-containing mixture predominantly - out of hydrocarbon С4 with usage of the catalysis by the strong-acid cationite(s) including the liquid-phase interaction of the isobutene with the water at the temperature of from 60 up to 130°С in one or several sections at the stage of hydration, delamination of the being withdrawn from it stream(s), distillation of the unreacted hydrocarbons С4 from the hydrocarbon layer, decomposing of the tret-butanol in the section(s) at the stage of dehydration, separation of the formed isobutene from the water and its) purification and characterized by that isobutene and the total amount of the returned from the stage of dehydration fresh water is fed in the section of hydration in the total molar ratio from 1:0.4 up to 1:20, and it is preferential from 1:1 up to 1:5, in the straight-flow or bubbling mode in the absence of the emulsifier hydrate from 30 up to 97 % of isobutene. From the stage of the hydration in the stage of the dehydration at least one-third of the produced tret-butanol is fed in the stream, separated by the rectification from the layer of the unreacted hydrocarbons and containing from 5 up to 30 mass % of the water, and, possibly, the rest amount - in the stream of the water layer, at the total content of the different, than the isobutene, the hydrocarbons not exceeding their admissible quantity in the target isobutene, and from the stage of the dehydration the water at least partially is returned into the stage of the hydration. The presented method requires the low power input and the low metal input.
EFFECT: the invention ensures the low power input and the low metal input.
14 cl, 2 dwg, 4 ex
FIELD: one-stage production of isoprene.
SUBSTANCE: proposed one-stage production method includes continuous or cyclic delivery of isobutylene and/or tert-butanol, formaldehyde and water to aqueous acid solution and interaction of reaction mixture at distillation of mixture containing isoprene to be produced, water, unreacted starting materials and other low-boiling components from reaction mixture beyond reaction system where said reaction is conducted at regulation of concentration of high-boiling byproducts which are accumulated in said reaction mixture at interval of from 0.5 to 40 mass-%.
EFFECT: enhanced efficiency.
10 cl, 2 dwg, 1 tbl, 13 ex
FIELD: industrial organic synthesis.
SUBSTANCE: production of styrene is effected via gas-phase dehydration of 1-phenylethanol at elevated temperature in presence of dehydration catalyst including molded particles of alumina-based catalyst having BET surface area 80 to 140 m2/g and pore volume (Hg) above 0.65 ml/g.
EFFECT: reduced amount of by-products and prolonged service cycle of catalyst.
3 cl, 1 tbl, 5 ex