| 摘要 |
PCT No. PCT/EP95/03068 Sec. 371 Date May 13, 1997 Sec. 102(e) Date May 13, 1997 PCT Filed Aug. 2, 1995 PCT Pub. No. WO96/05173 PCT Pub. Date Feb. 22, 1996Known processes for producing 2-hydroxy-4-methylthiobutyric acid (MHA) use a liquid-liquid extraction or a combined liquid/liquid and solid/liquid phase separation to isolate MHA from a reaction mixture produced by hydrolysing MMP-cyanhydrine. These processes are either costly or produce waste that is difficult to dispose of. These disadvantages are eliminated by isolating MHA by solid/liquid separation. The reaction mixture is evaporated until a MHA-containing salt residue with little or no residual water is obtained the MHA-containing, salt residue is treated with an organic solvent to produce a suspension, solid components are separated from the thus obtained suspension until a MHA-containing solution is obtained, the organic solvent is removed from the MHA-containing solution until a MHA residue is obtained and if required the MHA residue is then conditioned by water admixture. Besides high quality MHA, this process produces marketable crystalline ammonium sulphate and/or hydrogenated ammonium sulphate. This process is useful for producing feedstuff supplements.
|
