Acrylates and acrolein propenal

A variety of processes have been used for the production of esters of acrylic (propenoic) acid, including the solvolysis of acrylonitrile with c. H2SO4 and an alcohol. The Reppe process, commercialized by BASF and associated companies, is based on the reaction of acetylene with carbon monoxide, nickel carbonyl and an alcohol. However, the last U.S. operator of this process commissioned a propylene oxidation plant in October, 1982. 

Several companies have oxidized propylene to acrolein (propenal) on a modest scale, mainly for the production of methionine. All but Shell (copper catalyst) used catalysts similar to those for acrylonitrile production. Two-reactor or dual-catalyst systems have now been introduced to oxidize acrolein further to acrylic acid, most frequently over cobalt and molybdenum oxides. 

Growth in the traditional coating and textile applications of acrylic acid and acrylates is being extended by the use of polyacrylic acid as an absorbent (in diapers ) demand now exceeds 500 kilotonnes per annum in the U.S. and 250 kilotonnes per annum in western Europe. 

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