Modified Bentonite Adsorption Remobilised Class Pollutants And Its Mechanism

Bentonite is a montmorillonite clay as the main ingredient rock, because of itsgood adsorption, ion exchange, and etal., it can react with pollutants in aqueous solutionby adsorption, ion exchange, coagulation. Therefore, the bentonite as adsorbent hasbeen widely applied in wastewater treatment.In this paper, the calcium-based soil is purified, sodium, respectively, cetyltrimethyl ammonium bromide (CTMAB), benzyl triethylammonium chloride (BTMAC)organically modified, get the CTMAB modified soil BTMAC modified soil,modification of soil structure was characterized using X-ray diffraction (XRD), infraredspectroscopy (FTIR) and thermal analysis (DSC). The results obtained Na soil afterorganic modification, the interlayer spacing varying degrees of increase, which CTMAmodified△d=0.6729nm, BTMA modified soil△d=0.2175nm, indicating thatCTMA and BTMA ion have been inserted into the bentonite layer, increasing the layerspacing.In this study, the CTMA modified soil and BTMA modified soil adsorption insimulated wastewater of nitrobenzene and2,4-dichlorophenol analyzed using theLangmuir and Freundlich adsorption isotherm model experimental results, and in termsof thermodynamics, kinetics study the adsorption process. The experimental resultsshow that the modified bentonite on the adsorption of nitrobenzene in line with theLangmuir and Freundlich adsorption isotherm model,303K,50ml concentration10mg/L nitrobenzene simulated wastewater, the modified soil dosage of1g when Themaximum removal efficiency of62.34%. CTMA modified bentonites BTMA modifiedbentonite and sodium bentonite on the equilibrium adsorption amount of nitrobenzenewere0.3118mg/g,0.2560mg/g,0.04765mg/g, the adsorption is a spontaneousexothermic process, the adsorption kinetics of the quasi-second order kinetics equation.303K when the concentration is50mg/L of2,4-dichlorophenol wastewater by modifiedsoil dosage is0.4g, the maximum removal rate of2,4-dichlorophenol reached89.72%of CTMA modification of soil, BTMA modified soil and sodium soil equilibriumadsorption amount of2,4-dichlorophenol were5.6075mg/g,4.8963mg/g,0.7644mg/g, the adsorption is a spontaneous exothermic process. In addition, the modified soiladsorption of2,4-dichlorophenol in line with the Langmuir isotherm model.