Adsorption and desorption of three tetracycline antibiotics in petroleum-contaminated soils
Xie XiuJie · China Environmental Science · 2012
On the basis of the OECD Guideline 106,batch adsorption methods were employed to reveal the adsorption and desorption process of three tetracycline antibiotics in petroleum-contaminated soils.The Freundlich model was the best isotherm to describe all experimental data of adsorption and desorption(P0.01).In petroleum-contaminated soils,chlortetracycline adsorption isotherms resembled S-type curves,oxytetracycline adsorption isotherms resembled the L-type curves,and tetracycline adsorption isotherms resembled the linear curves according to adsorption strength(1/n value).The three antibiotics had strong adsorption in petroleum-contaminated soils,and the adsorption capacity(lgKf) was in the order of chlortetracycline(4.168 and 4.514) tetracycline(2.975 and 2.771) oxytetracycline(2.340 and 2.337).The dominant mechanism of three tetracycline antibiotics adsorption was physical adsorption in petroleum-contaminated soils.HI was in the order of oxytetracycline tetracycline chlortetracycline with significant difference(P0.01).For same antibiotic,the petroleum-contaminated extent could not affect the adsorption and desorption of three antibiotics in soil.Thus soil pollution would be greatly increased and complicated with the antibiotic occurring in petroleum-contaminated soils.