Phytoremediation of Azo-based Teztile Dyes
We have investigated the abilities of hydroponically grown sunflowers (Helianthus annuus), and water hyacinth (Eichhornia crassipes) to decolorize a range of textile dyes, at concentrations from 20-80 mg/L. Most studies were done in one-half strength Hoaglands nutrient solution to optimize the growth rate of the plants. Very different responses are sometimes obtained with dyes that have very similar structures, such as Evans Blue which is readily decolorized and Trypan Blue which is relatively recalcitrant. Many diazo dyes are effectively removed from solution while triphenylmethane derivitives are more resistant. Some dyes, such as Rose Bengal, are very toxic to the plants, others, such as Toluidine Blue are strongly sorbed but not fully decolorized. Sorption tests have been done with selected dyes using dried biomass, and pure cellulose (as filter paper), to correct for the sorption effect. Many dyes, originally used to dye cotton, are strongly sorbed to pure cellulose, particularly in the presence of salts. Tests have been done with a laccase mediator, hydroxybenzotriazole, to determine whether root surface laccase is involved in the degradation of various dyes. No evidence was found for its participation. Individual constituents of Hoaglands solution, and similar salts, were tested with Evans Blue and Methyl Red. Calcium, either as the nitrate or the chloride salt, markedly enhanced the rate of removal of Evans Blue from solution by plants, while magnesium salts were toxic. Potassium nitrate, KC1, trace elements, iron citrate, and potassium phosphate were little or no more effective than pure water. Decolorization of Methyl Red did not depend on ion addition. Calcium enhanced sorption of Evans Blue to dried roots or filter paper, but EDTA with 80 ％ methanol released the bound dye. The Evans Blue incorporated into live plants was not removable with this solvent.
dyes laccase perozidase lignin
H.C.Xie J.Ibbini A.J.Dickinson L.C.Davis L.E.Erickson
Department of Chemical Engineering Department of Biochemistry, Kansas State University, Manhattan, KS 66506 Department of Biochemistry, Kansas State University, 141 Chalmers Hall, Manhattan, KS 66506
国际会议
5th International Phytotechnologies Conference(第五届国际植物技术大会)
南京
英文
138-145
2008-10-22（万方平台首次上网日期，不代表论文的发表时间）