【摘要】 由工业单宁酸经乙酸乙酯溶剂萃取（５０～５５℃，１～２ｈ），制得药用单宁酸，其得率约为８５％，单宁酸含量超过９４％，乙酸乙酯的回收率超过９０％。经乙酸乙酯萃取的剩余水液可用于碱水解制备没食子酸。产物总得率（包括药用单宁酸和没食子酸）约为９１％。更多还原

【Abstract】 Pharmaceutical tannic acid was prepared from industrial tannic acid by ethyl acetate extraction at 50～55℃ for 1～2 h.The yield of the product was ca.85% which contained over 94% of tannic acid.The recovery of ethyl acetate was over 90%.The remaining liquor after ethyl acetate extraction could be used for preparing gallic acid by alkaline hydrolysis.Total yield of pharmaceutical tannic acid and gallic acid was ca.91%.更多还原