超临界CO_2络合萃取绿茶中Cu、Pb和Cd的研究

本文采用超临界CO2络合萃取法萃取绿茶中的Cu、Pb和Cd。分别考察了不同改性剂和络合剂、萃取压力、萃取温度以及静态和动态萃取时间对三种重金属的萃取率影响。研究结果表明:以磷酸三丁酯(TBP)/HNO3为络合剂,乙醇为改性剂,在20MPa、333K、静态和动态萃取时间分别为30min的最佳条件下,Cu、Pb和Cd的萃取率分别为78.3%、73.2%和69.5%。

Extraction of Copper, Lead and Cadmium in Green Tea by Supercritical Carbon Dioxide Chelating Extraction

In this paper, the extraction of copper, lead and cadmium in green tea by supercritical carbon dioxide chelating extraction (SCCE) has been investigated. The effect of pressure, temperature, static and dynamic extraction time and the type of modifier and ligand on the extraction efficiency were considered. Findings suggested that at the best condition of 20 MPa, 333 K, 30 min static extraction time and 30 min dynamic extraction time, with tri-n-butyl phosphate/nitric acid complex (TBP/HNO_3) as the ligand and ethanol as the modifier, the extraction efficiencies of Cu, Pb and Cd were 78.3%, 73.2% and 69.5%, respectively.