Abstract: An improved process is disclosed wherein 1,4-butanediol is produced from a maleic acid-containing solution in a multistep process comprising esterification of maleic acid at elevated temperature and pressure in the presence of a monohydric alcohol to form dialky esters of maleic acid, hydrogenation of the dialkyl esters to 1,4-butanediol in a two-step hydrogenation process, recovery of the 1,4-butanediol substantially free from other close boiling contaminants in an extraction zone and recovering 1,4-butanediol in high purity from a distillation zone operated at reduced pressure.

Abstract: Preparation of esters of maleic acid with monohydric alcohol by forming maleic anhydride by oxidizing a hydrocarbon in a maleic anhydride reaction, scrubbing the gaseous effluent to form aqueous maleic solution which is reacted and dehydrated in a first stage with monohydric alcohol in a distillation column. Reacting the product of the first stage under pressure and under conditions such that boiling occurs.