JPS5813575A - Preparation of gamma-butyrolactone - Google Patents

Abstract

PURPOSE:In preparing the titled compound by subjecting 1,4-butanediol to catalytic oxidative dehydrogenation with molecular oxygen, to improve the yield, by carrying out the reaction in the presence of a catalyst comprising platinum and copper without using a solvent. CONSTITUTION:1,4-Butanediol is subjected to catalytic oxidative dehydrogenation with molecular oxygen in the presence of a catalyst comprising platinum and lead at 0-250 deg.C, preferably at room temperature -220 deg.C at normal pressure - tens atmospheric pressure, to give the desired compound. The catalyst may be used in unsupported state, a carrier is preferably used with respect to reaction and economic points, and especially active carbon, graphite, alumina, etc. may be cited as the carrier. The amount of platinum in the supported carrier is 0.1- 20wt%, preferably 0.5-10wt%, and the amount of the lead compound is an amount to give an atom ratio of lead to platinum of 0.01-50, preferably 0.1-10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing r-butyloctone. According to the OI production method of the present invention, 1.4
1-Butyrolactone can be obtained from -butanediol.

Conventionally, r-butyrolactone is anhydrous! Leic acid O hydrogenation,
Alternatively, it is prepared industrially by dehydrogenation of 1,4-butanediol. The latter method uses 1. '4-Butanediol is produced* by hydrogenating the reaction product of acetylene and formalin, so it was not necessarily an advantageous method because it was expensive. However, in recent years, 1.4 -The method for synthesizing butanediol is
By reaching an industrial level, it is possible to obtain inexpensive 1,4-butanediol, and it is attracting attention as a more advantageous method than the former. However, in the latter method, the reaction is carried out using a supported catalyst containing steel in the gas phase, but the reaction temperature is high (for example, British Patent No. 1.066.9 'I
(see No. 9), the catalyst deteriorates over time.

This poses an operational problem for the papermaking industry, which requires regeneration of the catalyst. As a method to solve this problem, a method has been proposed in which 1,4-butanediol is catalytically oxidized and dehydrogenated under mild conditions to produce r-butyrolactone. Round method using platinum (see JP-A No. 185!-24107)
, using intermetallic compounds consisting of specific elements including palladium and lead.

How to do it←Refer to Japanese Patent Application Laid-Open No. 5A-153740 l1l)
is disclosed. However, with these methods, the yield of r-butyrolactone cannot be said to be at a practical level.

In order to find a catalyst that is satisfactory from an industrial standpoint, the present inventors conducted extensive studies and discovered that r-butyrolactone can be obtained at an extremely high yield by using a catalyst containing platinum and lead. That is, the present invention uses a catalyst containing todosho, platinum, and lead to produce r-butyro2chton by catalytic oxidation and dehydration of 1,4-butanediol with molecular oxygen. K provides a manufacturing method characterized by:

The method of the present invention can be carried out by reacting 1,4-butanediol alone in a liquid phase or gas phase without using a solvent, but an organic solvent unrelated to the reaction can also be used. Han, 1 is an organic solvent that can be used in the 0III manufacturing method.
．． Any material that can dissolve or disperse 4-butanediol may be used, such as ethers such as leethyl ether, diethylene glycol diethyl ether, anisole, tetrahydrofuran, and dioxane, nitriles such as propionitrile, and amides such as N-methylpyrrolidone. esters such as ethyl acetate, lactones such as r-butyrolactone, ketones, nitro compounds, hydrocarbonated aromatics, and the like. First, alcohols can be used as a solvent, but this is not preferable because the solvent itself undergoes an oxidation reaction and by-products such as esters other than the desired product increase. The amount of solvent used varies depending on the reaction temperature, amount of catalyst, reaction time, etc., but is 0.5 to 400 times, preferably 1 to 200 times, by weight relative to 1.4-butanediol. is used. Although the catalyst can be used unsupported, it is preferable to use a carrier from the reaction and economical viewpoints. 41 activated carbon, graphite,
A1, silica, calcium carbonate, etc. are preferred.

As the platinum compound serving as the catalyst raw material used in the present invention, platinum chloride, platinum chloride, ammonium chloroplatinate, etc. are preferably used, but it is also possible to use dinitrediaelectroplatinum, etc. When using a single carrier , there is no limit to the amount of platinum supported, but the amount of platinum in the supported catalyst is 01
1 to 10 wt%, preferably 10% to 10% by weight. Lead compounds include lead salts such as inorganic acid salts such as nitric acid, sulfuric acid, hydrochloric acid, and boric acid, as well as formic acid, acetic acid, propionic acid, Organic acid salts such as malonic acid, succinic acid, glutaric acid, maleic acid, and benzoic acid, oxides, and hydroxides can be used, and the amount added is 0.01 to 50 in atomic ratio to platinum. The ratio is preferably 0.1 to 10 times.

In addition to platinum and lead, the catalyst of the present invention may contain one or more elements such as palladium, copper, germanium, soot, alkali metals such as sodium, and alkaline earth metals such as magnesium. For supporting the catalyst component O, the omniscient method for preparing supported metal catalysts can be used in Tateshima.Platinum, lead, and the above-mentioned elements may be supported at the same time, or they may be supported separately at different stages of catalyst preparation. It is also possible to support the catalyst by using a well-known method for the reduction operation, but it is also possible to prepare a paper-based catalyst by appropriately repeating the reduction-oxidation process.
On the other hand, a solution containing the above-mentioned lead and a compound of the above-mentioned elements is supported on a commercially available platinum-activated carbon or platinum-aluminum catalyst by a method such as dipping, and then dried. Catalysts that have been treated with oxidation or the like can be similarly used in the method of the present invention. The molecular oxygen used in the reaction does not need to be pure oxygen, but rather inert oxygen.
It may also be oxygen diluted with gas, such as air. The reaction temperature was o-zs.

°C, preferably room temperature to 220 °C is used. Although the reaction pressure line is not limited, the zero reaction, which is usually carried out under normal pressure to several tens of atmospheres of pressure, can be carried out in either a batch type or a continuous type. Next, the present invention will be explained in further detail by giving Examples and Comparative Examples. In addition, "u" in the analysis results in Examples and Comparative Examples means "r morra".

Example 1 1,4-butanediol St was converted into dioxane 5OtKil
Scale it and charge it into a four-loaf flask equipped with a gas inlet, a stirrer, a cooler and a temperature needle, and then add this liquid W.
16W as a metal on c5Wt9 & platinum-active rock catalyst (Japan Engelhard shaved)! % of lead acetate supported and dried, 2.52% of the catalyst was added, air was introduced into the solution at a flow rate of 11 $0114 I/min, and the reaction was carried out under normal pressure for 80 C1S, and the above platinum-activated carbon catalyst was After the completion of the reaction, which is a commercially available product but has been reduced in advance, it was analyzed using a gas chromatograph, and a yield of 81.2% was obtained as r-butylactone, which was 9,1,4-butane. Diol conversion rate 14. ! ! %, r-butylocton selectivity is 8
5.9 shi motsu 9.

Example 1 #1 of 4-butanediol, 201. of r-butyrolactone as a solvent. Reaction temperature: 75°C and reaction time: 3
Time and nine others are lI! Carry out the reaction in the same manner as in Vaginal Example 1.

After the reaction was completed, analysis was performed in the same manner as in Example 1, and the results were r-
Yield as butylocton: 74%, 1,4-butanediol conversion rate: 90%, r-butylocton selectivity: 82%
Met.

Comparative example 1! The reaction was carried out in the same manner as in Example 1, except that a swt% platinum-activated carbon catalyst (manufactured by Nippon Kougernolt Co., Ltd., which had been reduced in advance) was used. As a result of analysis, r-
Yield as butyrolactone 3.6%, 1,4-butanediol conversion rate 22.6%, r-butyrolactone selectivity 1
6.0% and 9.

From the above Examples and Comparative Examples, it is clear that the production method of the present invention is superior.

Claims (1)

[Claims] 1. A production method for producing r-butyrolactone by catalytic oxidative dehydrogenation of 4-butanediol using molecular oxygen, using a catalyst containing platinum and lead.