| 摘要 |
<p>Processes are disclosed for producing lactic acid, esters of lactic acid, acrylic acid, and esters of acrylic acid, primarily from fermentable carbohydrate materials. An overall process for producing esters of acrylic acid comprises: a) fermenting carbohydrate material with a lactic-acid-forming organism in the presence of NH3 to produce ammonium lactate; b) combining the ammonium lactate with an alcohol; c) combining the ammonium lactate and alcohol with an effective catalyzing amount of gaseous CO2 to catalytically esterify the ammonium lactate and alcohol into a lactic acid ester containing solution; d) recovering purified lactic acid ester; and e) vaporizing the lactic acid ester and passing it through a solid catalyst bed comprised of an effective catalyzing amount of crystalline hydrated and partially calcined calcium sulfate to catalytically convert lactic acid ester into an acrylic acid ester. Step "d" would be useful in a process for making low-cost, purified lactic acid. Similarly, step "e" would be useful in a process for making low cost, purified acrylic acid.</p> |
