| 摘要 |
The process is partic. applied to an aq. alcoholic extract obtd. from grapes or grape prods., pref. grape residues from wine making. The reverse osmosis is pref. preceded by ultrafiltration, partic. using membranes giving a mol. wt. of 1,000-70,000, esp. about 20,000 at 2-40 kg./-cm2, esp. about 10 kg./cm2. Before the osmosis, the tartrates are removed by pptn. and sepn. The membrane for osmosis has an NaCl retention power of 30-99%, esp. 50-90%; a CaCl2 retention power of 70-99.8%, esp. 75-99.7%; specifically an 85% NaCl, 99.5% CaCl2 and 100% saccharose retention. The pressure used in the osmosis is 10-100 kg./cm2, esp. about 50 kg./cm2. Alcohol is recovered from the diffusate. Process avoids problems of degradation and contamination associated with previous processes. |
