Removal Of Pesticide Residue From Ginseng Extract With Organic Montmorillonite

Ginseng,as one kind of rare medical herds,have the efficacy of retarding aging,enhancing immunity,reinforcing body fluid and nourishing the blood,stimulating the circulation of blood and lowering blood pressure.one of the main evaluating factor of the Ginseng's quality is its pesticide residue is of important practical value.In this work,we first simulate the pesticide adsorption in water,then evaluated the ability of bentonites exchanged with five natural organic cations containing diverse functional groups: Hexadecyltrimethylammoniumbromide(CTMAB), titanium buty- rate (TBTI), thiamine(VB1), Cysteine(CYS), phenyltrimethylammonium(PTMA) as adsorbents of pesticides varying in their chemical structures (quintozene,α-BHC, Aldrin, pp′-DDT).The results show that these four pestcides display the higher affinity for CTMAB -treated bentonites and PTMAB -treated bentonites.The CTMAB-MMT treated with different quantity CTMAB take on different layer structures.The CTMAB-MMT treated with 0.5CEC CTMAB has the highest affinity for the four pesticides. Pesticide(α-BHC, Aldrin, quintozene, pp′-DDT) adsorption isotherms were fitted to the Freundlich equation: Cs =KfCeNf.In Ginseng extract , calcinatory PTMAB-MMT show the highest affinity to the four pesticides among four sorbent(CTMAB-MMT, PTMAB-MMT, ,heat treatmented CTMAB-MMT, heat treatmented PTMAB-MMT).There being particle concentration effect in the adsorption of pesticides in Ginseng extract with heat treatmented PTMAB-MMT;Organic montmorillonite could strongly neutralize acidic or alkali Ginseng extract,so the pH value don't affect much of adsorption between pesticides and heat treatmented PTMAB-MMT;The adsorption column filled with heat treatmented PTMAB-MMT show prominence effect in the adsorption of pesticides in Ginseng extract,only traceα-BHC was detected in the four pesticides.The analysis of Ginsenosides by high performance liquid chromatography/mass spectrometry show that the loss of Ginsenosides was subter 4%Organic montmorillonite was characterized by XRD,XPS,FTIR.DTA-TG and TEM measurement.Based on the experimental results ,the powder XRD analysis was performed to determine the interlayer spacing of Organic -MMT to analysis the status of organic chains.It is clear that the interlayer spacing of MMT increased after modification,which indicated that the organic reagents had intercalated into the layers of Na-MMT by cation exchange. heat treatmented PTMAB–MMT lost interbedded water and increase the content of organic cations.