Purification Of Polluted Water Of The Pb-cd, Cress And Iris Body And Repair Test

At present, the heavy metal pollution causes the attention by us gradually. This also becomes the difficult problem and focus in studying water environment pollution at home and abroad. As a country being abundant in coal natural resources, it is a new subject by carrying out phytoremediation technology in heavy metal mining areas.In this paper, the heavy metal pollution is investigated and assessed in the heavy mining areas of GuangXi province. Plants growth and heavy metal accumulation of accumulating ecotypes of the selected planted were studied by hydroponics experiments. On the basis of preliminary experiment, the effects of oenanthe javaniaca BI. and Acorus calamusL. on single Pb or Cd, and Pb-Cd compound pollution were studied.Firstly, to elucidate the characteristics of single Pb or Cd in aquatic plants, a series of chemical, biochemical analytic techniques were used to study the growth, the absorption, the removing efficiency of Pb or Cd, the accumulation and physiological response of the plants. The results show that: both oenanthe javaniaca BI. and Acorus calamusL. could grow well in the solution culture experiment, and the purifying efficiency of Acorus calamusL. was superior to oenanthe javaniaca BI.. The removal rates of Pb, Cd by Acorus calamusL. were 90.4%, 87.5% respectively; and that of Pb, Cd by oenanthe javaniaca BI. were 74.7%, 73.3%.Secondly, using the method of aquatic culture, the growing responses, the accumulating charactertics of oenanthe javaniaca BI. and Acorus calamusL. with high tolerance to Pb-Cd compound pollution and the relationship between Pb and Cd reported in the previous study were further investigated. For the two aquatic plants, the interactive effect of Pb and Cd was complicated, not simply additive, antagonist and synergistic, but also related with many factors, including various concentration combinations of heavy metals, plant species and different tissues.Thirdly, the study investigates the mechanism of heavy metal ions(Pb²⁺, Cd²⁺) adsorption of oenanthe javaniaca BI. and Acorus calamusL. was analyzed by the intraparticle diffusion modle, the pseudo-first-order and the pseudo-second-order equations. The results indicate as follow: adsorptions of Pb²⁺, Cd²⁺ onto oenanthe javaniaca BI. and Acorus calamusL. are multi-linear processes including three processes; the calculated Qe values obtained from linear regression of the Lagergren equation is far deviated from the experiment data. In addition, it was observed that the sorption data were well represented by the lagegren modle only for the first process; and comparison of error analysis of the intraparticle model, the pseudo-first-order and pseudo-second-order equations, the result show that the order of deviation was intraparticle diffusion model> the pseudo-first-order >pseudo-second-order. It was confirmed that the pseudo-second-order was the best one in describing the adsorption kinetics of Pb²⁺,Cd²⁺ onto oenanthe javaniaca BI. and Acorus calamusL..