Korea Institute of Science and Technology

Korea Advanced Institute of Science and Technology

Sung J Uhm

Jun W Oh

Oh S Joo

Sung H Han

Kwang Deog Jung

Eun Sil Choi

Moon Sue Lee

Tae Jae Lee

Jung Y Beak

Dong W Yu

The present invention provides an improved process for selectively producing acetic acid and/or methyl acetate by the gas phase carbonylation of methanol with carbon monoxide; an improved process for producing acetic anhydride directly from the methyl acetate; and a novel method for sustaining the life time of a carbonylation or a hydroformylation catalyst by pretreating the carbon monoxide or the synthesis gas to be used in carrying out the gas phase carbonylation or the hydroformylation.

Processes for the carbonylation of methanol to form acetic acid, methyl

Acetic ester is produced economically by a gas phase carbonylation of methanol with carbon monoxide followed by a transesterification. Specifically, the inventive process comprises (a) carbonylating methanol in a gas phase with carbon monoxide to produce a mixture of acetic acid and methyl acetate; (b) separating from the production mixture the acetic acid, and a mixture of the methyl acetate and the co-catalyst; (c) further separating said methyl acetate and the co-catalyst and recycling the separated co-catalyst to the carbonylation reactor; (d) introducing the separated methyl acetate into a lower region of a transesterification reactor at a temperature of above its boiling point; (e) introducing an C.sub.2 or higher alcohol into an upper region of the trans-esterification reactor at a temperature of up to its boiling point; (f) transesterifying the methyl acetate with the alcohol in the presence of an acid catalyst to produce a mixture containing acetic esters; and (g) recovering the acetic esters from the mixture as a bottom product while recycling the unreacted methyl acetate and methanol to the carbonylation reactor or distillation column.

Process for the preparation of acetic esters from methanol

Ethanol is produced economically by a gas phase carbonylation of methanol with carbon monoxide followed by a hydrogenation. Specifically, the inventive process comprises:

Process for the preparation of ethanol from methanol

A process for preparing phthalic acid esters of formula (I) which comprises reacting the phthalic acids of formula (II) with an aliphatic alcohol in the presence of a catalyst consisting essentially of the dialkyltinoxides of formula (III): ##STR1## wherein R and R.sub.1 are the same or different and include both straight and branch chain aliphatic alkyl groups containing 4 to 13 carbon atoms and R.sub.2 and R.sub.3 are straight or branch chain aliphatic alkyl groups containing 1 to 8 carbon atoms.

Process for producing phthalic acid esters

Growing community of inventors

Seoul, South Korea

Sung J Uhm