Research On The Adsorption Properties Of The Containing Lead Wastewater With Radix Isatidis

With the development of industrialization in the past decades, the discharge ofwastewater is increasing, which leads to serious environmental pollution. And the mainpollution sources of heavy metal lie in mining, milling and surface polishing industrieswhich will discharge, in their production process, the wastewater containing a variety oftoxic heavy metals such as Cu, Zn, Cd and Pb. When the heavy metals melted into thewater and accumulated together, they will do great harm to human beings by going intothe bodies through the food chain.Conventional technologies such as chemical precipitation, oxidation/reduction, ionexchange, electrolysis and membrane filtration have been used in the removal of heavymetals from wastewater. These technologies are most suitable in situations where theconcentrations of the heavy metal ions are relatively high, when heavy metals arepresent in the wastewater at low concentrations; they are potentially risky due to thecomplex process of production, large investment of equipments and the possibility ofthe generation of hazardous by-products. Thus an efficient and low-cost way oftreatment is urged to deal with the heavy metals in the wastewater. Biosorption appearsto offer a technically feasible and economically attractive approach.This paper studies the features of biosorption of lead by Rradix Isatidis. It wasfound that Radix Isatidis could adsorb lead in the wastewater quickly, especially in thecondition when pH is between6.0and7.0, the adsorption time is about3hours. TheRadix Isatidis’ capacity of lead adsorption rate rose from87.1%to88.82%by usingAcid-base method to interfere. The adsorption of Pb2+by Radix Isatidis residueconforms to Freundlieh’s Adsorption Isotherm, with linear regression coefficient of0.9977. Utilizing it into Langmuir’s Adsorption Isotherm is of a good coincidence withlinear regression coefficient of0.9864.