Under different modified ratios, temperatures, pH and ionic strengths, the effect of sodium dodecyl sulfonate (SDS) on the adsorption of Cd2+ onto bentonites which modified with amphoteric modifier dodecyl dimethyl betaine (BS-12) was studied by batch experiments, and the adsorption mechanism was also discussed. Results showed that the adsorption of Cd2+ on amphoteric bentonites can be enhanced significantly by SDS combined modification, Cd2+ adsorption decreases in the order: BS + 150SDS (BS-12 + 150% SDS) > BS + 100SDS (BS-12 + 100% SDS) > BS +50SDS(BS-12 + 50% SDS) > BS + 25SDS (BS-12 + 25% SDS) > BS (BS-12) > CK (unmodified soil). The adsorption isotherm can be described by the Langmuir equation.
View Article and Find Full Text PDFHighly ordered channel structure SBA-15 was widely concerned as new adsorbents in environmental protection, in order to increase its heavy metal ions adsorption ability from aqueous solution, the diamine -modified porous silicate SBA-15 was synthesized by a hydrothermal grafting method and characterized by TEM, X-ray diffraction, FTIR and N2 adsorption-desorption. The SBA-15 and modified SBA-15 samples were used as sorbents to adsorb Cd(II) ions from aqueous solution. The effect of experimental parameters, such as pH, contact time, sorbent dosage and temperature were examined, and the maximum adsorption amount was also calculated.
View Article and Find Full Text PDFBecause of its strong chelation, solubilization characteristics, the chelating agents and biosurfactant are widely used in remediation of heavy metals and organic contaminated soils. Ethylenediamine tetraacetic acid (EDTA), citric acid (CIT) and dirhamnolipid (RL2) were selected as the eluent. Batch experiments and column experiments were conducted to investigate the leaching effect of the three kinds of eluent, as well as the mixture of biosurfactant and chelating agent for Cu, Pb contaminated loess soil.
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