摘要
Tea polyphenols(TP) were prepared by a complexing precipitation processs with an aluminium salt as the complexing agent.This study mainly focuses on the recycle of the complex agent,and the effect of Fe3+ content on the product yield was investigated.At 3050 ℃ and pH 56,the TP in 200 g of green tea formed complex with 65 g of hydrous(aluminium) chloride.The precipitate obtained was washed with deionized water thoroughly,acidified with 10% hydrochloric acid, and then extracted with an equivalent volume of ethyl acetate.The ethyl(acetate) solution of TP was concentrated to produce crude TP with a yield of up to 11.94% and a purity of 90%.The experimental data also show great reduction in TP yield when Fe(Ⅲ) was involved in the precipitation process of the aluminium salt.In the absence of ferric iron,the aluminium complex agent can be recycled at least 3 times with TP yields of more than 10% and the purity higher than 88%.
Tea polyphenols(TP) were prepared by a complexing precipitation processs with an aluminium salt as the complexing agent. This study mainly focuses on the recycle of the complex agent, and the effect of Fe^3+ content on the product yield was investigated. At 30 - 50℃ and pH 5 - 6, the TP in 200 g of green tea formed complex with 65 g of hydrous aluminium chloride. The precipitate obtained was washed with deionized water thoroughly, acidified with 10% hydrochloric acid, and then extracted with an equivalent volume of ethyl acetate. The ethyl acetate solution of TP was concentrated to produce crude TP with a yield of up to 11.94% and a purity of 90%. The experimental data also show great reduction in TP yield when Fe( Ⅲ) was involved in the precipitation process of the aluminium salt. In the absence of ferric iron, the aluminium complex agent can be recycled at least 3 times with TP yields of more than 10% and the purity higher than 88%.
出处
《应用化学》
CAS
CSCD
北大核心
2005年第12期1387-1389,共3页
Chinese Journal of Applied Chemistry
关键词
茶多酚
络合沉淀法
络合剂的循环利用
tea polyphenols, complexing precipitation process, recycle of complex agent