Stephen Westley Brewer

US Patent:

6969779, Nov 29, 2005

Filed:

Oct 1, 2003

Appl. No.:

10/676690

Inventors:

Stephen Edward Brewer - Houston TX, US
Zaida Diaz - Houston TX, US
Joseph Broun Powell - Houston TX, US
Paul Richard Weider - Houston TX, US
Glenn Charles Komplin - Houston TX, US
Robert Lawrence Blackbourn - Houston TX, US

Assignee:

Shell Oil Company - Houston TX

International Classification:

C07C027/04
C07C029/14
C07C031/18
C07C027/26
C07C029/74

US Classification:

568862, 568852, 568861, 568868, 568872

Abstract:

The present invention is an improvement upon the process for the production of 1,3-propanediol (PDO) wherein an aqueous solution of 3-hydroxypropanal (HPA) is formed, and the HPA is subjected to hydrogenation to produce a crude PDO mixture comprising PDO, water, MW176 acetal, and high and low volatility materials, wherein the crude PDO mixture is dried to produce a first overhead stream comprising water and some high volatility materials and a dried crude PDO mixture as a first distillate bottoms stream comprising PDO, MW176 acetal, and low volatility materials, and wherein the dried crude PDO mixture is distilled to produce a second overhead stream comprising some high volatility materials, a middle stream comprising PDO and MW176 acetal, and a second distillate bottoms stream comprising PDO and low volatility materials. The improvement on this process comprises treating the crude PDO mixture and/or the dried crude PDO mixture and/or the PDO product with an acidic zeolite, an acid form cation exchange resin, or a soluble acid to convert the MW176 cyclic acetal to more volatile materials which can be easily separated from PDO by distillation.