Organic compounds -- part of the class 532-570 series – Organic compounds – Oxygen containing
Reexamination Certificate
1999-08-06
2001-02-20
O'Sullivan, Peter (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Oxygen containing
C054S050000
Reexamination Certificate
active
06191322
ABSTRACT:
DESCRIPTION
The present invention relates to a process for the production of 1,4-butanediol, and particularly it relates to the employment of mixed phase flow catalytic hydrogenation of gamma-butyrolactone, succinic anhydride esters, or mixtures thereof.
It is known from the prior art that there exist several processes for production of 1,4 butanediol (BDO) from dicarboxylic acid esters with four carbon atoms as starting materials.
In USSR Patent No. 400,567 a copper chromite catalysed liquid phase conversion of esters into BDO at temperatures ranging between 280 and 300° C. and 300 bar pressure is given.
In U.S. Pat. No. 4,613,707 a conversion of diethylsuccinate into BDO at 200° C. T and 135 bar pressure with a mainly copper and aluminium borate catalyst is given.
In U.S. Pat. No. 2,079,414 a vapour phase hydrogenation of esters is given, on a copper chromite type catalyst and temperatures ranging between 300 and 400° C.
In U.S. Pat. No. 204,944 a broad description of both liquid and vapour phase ester hydrogenations is given, using copper chromite catalysts. In one example, a liquid phase butyl succinate hydrogenation at 207 bars is described.
In U.S. Pat. Nos. 4,584,419 and 4,751,334, owned by Davy Mc Kee Ltd. (U.K.) processes for the large scale production of BDO are described, wherein 4 carbon dicarboxylic acid hydrogenations are resorted to.
In the above processes, the hydrogenation rections take place in two sequential stages in the vapour phase, and in the presence of a copper chromite type hydrogenation catalyst.
According to the processes assigned to Davy Mc Kee Ltd., each of the two hydrogenation stages occurs in the conditions ranging between the following values:
Pressure: between 25 and 70 bars
Temperature: between 150° and 200° C.
H
2
/ester ratio: between 100/1 and 800/1
1,4-butanediol synthesis from gammabutyrolactone (GBL) is mentioned in German Patent No. 2,144,316, assigned to Mitsubishi Corporation of Japan. Conversion is carried out on a nickel-cobalt catalyst, at temperatures between 200 and 250° C. and pressures between 100 and 120 bars.
In Belgian Patent No. 892,958 a vapour phase hydrogenation process of GBL to BDO is given, at pressures between 15 and 30 bars, and temperatures ranging between 200 and 230° C., on a copper-zinc oxide based catalyst.
In U.S. Pat. No. 4,652,685 a similar process is described, and this is carried out in the vapour phase and at 40 bar pressure, 210° C. and on a barium stabilised copper chromite type catalyst.
In German Patent No. 3,903,563 a process is described wherein reaction pressure is 60 bars and a cobalt-copper catalyst is employed.
The conditions to maintain vapour or mixed flow conditions being strictly necessary, all solutions so far proposed for a process for the production of 1,4-butanediol present two types of problems both of which considerably affect costs.
One relates to the large amount of hydrogen needed, more so if compared with the actual amount of this gas which goes to react with the starting material; the other stems from the need to reduce the catalyst before use, operation which is also time consuming, as it entices an at times long phase prior to the process itself.
It is therefore an aim of the present invention to propose a process for the production of 1,4-butanediol which is speedy and cost effective as in this catalysts in their unreduced forms are used, and a very much smaller amount of H
2
is used than in anyone of the processes objects of the patents and methodologies in the prior art.
Such aims are accomplished by a process for the production of butanediol by selective catalytic hydrogenation of gamma-butyrolactone, succinic anhydride esters or mixtures of gamma butyrolactone and succinic anhydride esters, characterised by the fact that it occurs in at least two catalytic stages at a pressure ranging between 60 and 100 bars and temperature ranging between 160 and 250° C. which are characterised with the presence of a liquid phase at the entrance of the first stage.
REFERENCES:
patent: 2079414 (1937-05-01), Lazier
patent: 3772395 (1973-11-01), Yamaguchi et al.
patent: 4613707 (1986-09-01), Kouba et al.
patent: 4652685 (1987-03-01), Cawse et al.
patent: 4751334 (1988-06-01), Turner et al.
patent: 5334779 (1994-08-01), Kuo et al.
patent: 892958 (1982-08-01), None
patent: 2144316 (1972-03-01), None
patent: 3903363 (1990-08-01), None
patent: 0382050 (1990-08-01), None
patent: 400567 (1973-10-01), None
O'Sullivan Peter
Pantochim S.A.
Stevens Davis Miller & Mosher LLP
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