[Study on adsorption of tea polyphenol and caffine with polyamide resin].
The performance of adsorption of tea polyphenol and caffine with polyamide resin was investigated. The results obtained by spectrophotometry and HPLC show that the ability of adsorption of tea polyphenol with polyamide is stronger than that of caffine, in which hydrogen bond plays a very important role. The adsorption amount of caffine is 2.65 mg.g-1 with 7.5% adsorption ratio when 100 mL of 0.71 g.L-1 caffine is adsorbed on polyamide resine, but the adsorption amount of tea polyphenol is up to 148.13 mg.g-1 with 85% adsorption ratio when 700 mL of 1.98 g.L-1 tea polyphenol is adsorbed on polyamide resine. The dilution ratios of caffine and tea polyphenol are 74% and 90%, respectively, when they are diluted by 85% alcohol. The static adsorptions of caffine and tea polyphenol on polyamide resine reach equilibrium quickly in 80 min, and the plots of adsorption kinetics are nearly linear. Tea polyphenol and caffine are successfully separated on polyamide resine, and the obtained product contains more than 96% of tea polyphenol and 80% of EGCC with caffine less than 2.8%.
Tang
Ke-wen
KW
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
Zhou
Chun-shan
CS
Zhong
Shi-an
SA
Zhu
Jie-ding
JD
D000327:Adsorption; D002110:Caffeine / Q000032:analysis / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005419:Flavonoids / Q000032:analysis*; D009757:Nylons; D010636:Phenols / Q000032:analysis*; D059808:Polyphenols; D012117:Resins, Synthetic; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013662:Tea / Q000737:chemistry*
D005419:Flavonoids; D009757:Nylons; D010636:Phenols; D059808:Polyphenols; D012117:Resins, Synthetic; D013662:Tea; D002110:Caffeine