摘要:
Disclosed is a process for the preparation of tertiary olefins which comprises catalytically decomposing a tertiary ether to a tertiary olefin, wherein the catalytic decomposition of the tertiary olefin is carried out in the presence of a solid phosphoric acid catalyst which has been calcined at a temperature of at least 500.degree. C. in an inert gas.
摘要:
A commercially economical process for preparing a carboxylic acid ester from a carboxylic acid amide is disclosed. The process is very meritorious, since it produces neither ammonia nor ammonium sulfates. Rather, the process by-produces formamides which are very useful compounds as solvents. Further, formamide can easily be converted to hydrogen cyanide by dehydration. The process comprises reacting a carboxylic acid amide with a formic acid ester and/or methanol and carbon monoxide in the presence of a bicyclic amidine or tertiary amine catalyst and optionally in the co-existence of a metal carbonyl. An industrial process for preparing methyl methacrylate which is a materialization of the process shown above is described in detail referring to a figure.
摘要:
Disclosed is a process for producing methyl methacrylate which comprises:(I) a step of reacting acetone and prussic acid to form acetonecyanhydrin;(II) a step of hydrating the acetonecyanhydrin obtained in the step (I) to form .alpha.-hydroxyisobutyric acid amide;(III) a step of reacting the .alpha.-hydroxyisobutyric acid amide obtained in the step (II) which methyl formate to form methyl .alpha.-hydroxyisobutyrate and formamide;(IV) a step of dehydrating the methyl .alpha.-hydroxyisobutyrate obtained in the step (III) to form methyl methancrylate; and(V) a step of decomposing the formamide obtained in the step (IV) into ammonia and carbon monoxide.The process can produce methyl methacrylate at high yields without by-production of acidic ammonium sulfate.
摘要:
A method for preparing an alkylbenzoic acid is herein disclosed which comprises subjecting an alkylbenzene having at least two alkyl groups of 1 to 3 carbon atoms to a liquid phase oxidative reaction with a molecular oxygen-containing gas in the presence of a soluble heavy metal catalyst to convert one alkyl group into a carboxylic acid, thereby preparing the alkylbenzoic acid, and impurities contained in the alkylbenzene recovered from the reaction solution are removed therefrom by distillation, water washing, alkali washing, a treatment with an anion exchange resin or a treatment with a solid adsorbent, and the impurities-free fraction is reused as a raw material. Furthermore, the conversion of the desired product is regulated to 25% or less in the liquid phase oxidative reaction, whereby the reaction is carried out in a boiling heat removal state and reaction heat is removed as the heat of vaporization. Thus, there can be decreased a dicarboxylic acid secondarily produced during the manufacture of the alkyl-benzoic acid which is a monocarboxylic acid by subjecting the alkylbenzene to the liquid phase oxidation, whereby problems such as the trouble of equipment operation and the deterioration of product quality can be solved.
摘要:
A process for producing an .alpha.-hydroxyisobutyric acid which comprises hydrolyzing .alpha.-hydroxyisobutyric acid ester in the presence of an organic sulfonic acid catalyst, using an .alpha.-hydroxyisobutyric acid ester as the starting material.According to said process, .alpha.-hydroxyisobutyric acid can be efficiently produced.
摘要:
Carboxylic acid esters and formamide are efficiently obtained for reacting carboxylic acid amides and formic acid esters, or carboxylic acid amides, alcohols and carbon monoxide in the presence of an alkaline earth metal oxide catalyst.
摘要:
Disclosed is a process for producing .alpha.-hydroxy-carboxylic acid amide represented by the formula (I): ##STR1## wherein R.sup.1 and R.sup.2 are as defined in the specification, by a catalytic hydration reaction of cyanohydrin represented by the formula (II): ##STR2## which comprises using a modified manganese dioxide containing one or more of an alkali metal element and an alkaline earth element in an amount of 0.05 to 0.5 based on the manganese element in terms of atomic ratio.
摘要:
A tertiary olefin is produced by contacting a gaseous tertiary ether usually represented by the following general formula: ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are alkyl groups each having 1-4 carbon atoms which may be same or different and R.sup.4 is an alkyl group having 1-3 carbon atoms, with a catalyst obtained by calcining a silica-alumina compound at 700.degree.-1100.degree. C. in order to effect cracking of the tertiary ether. This reaction may be carried out in the presence of steam to result in further improvements.
摘要:
In an assembly line in which at least two kinds of workpieces are transported by mixture and in which each of the workpieces is transported by a self-propelling transporting member, a transporting pitch for each kind of workpiece is set in advance based on a difference in the number of assembling man-hours required for each of them. The timing for starting the transporting member off a starting end of the assembly line is controlled according to the transporting pitch such that a pitch between a preceding transporting member and a succeeding transporting member becomes equal to that which is set for a workpiece to be transported by the preceding transporting member.
摘要:
A process for producing .alpha., .beta.-unsaturated carboxylic acid ester which comprises catalytically reacting .alpha.-hydroxycarboxylic acid ester with crystalline aluminosilicate catalyst, and then catalytic reacting the resulting reaction product with solid acid catalyst.According to the process, .alpha., .beta.-unsaturated carboxylic acid ester of a high purity, and a high quality, without by-product, can be produced efficiently.