Study on adsorption performance of cross-linked carboxymethyl corn starch on methylene blue in aqueous solution

Adsorption of methylene blue by cross-linked carboxymethyl corn starch was studied in simulated wastewater.Effects of the adsorbent content, pH, reaction time and dye concentration on the adsorption performance to methylene blue in aqueous solution were studied on the basis of the results of single factor tests.Also the adsorption isotherm and adsorption kinetics of cross-linked carboxymethyl corn starch on methylene blue in aqueous solution were studied.Results showed that the adsorption rate of methylene blue reached 95.66%under the condition of dye concentration 100mg/L, pH6.0, adsorbent content 0.2g, adsorption temperature 25℃and adsorption time 60min.The theoretical saturation adsorption amount of cross-linked carboxymethyl corn starch was 80mg/g at 25℃.The isotherm indicated that the adsorption process followed the Langmuir adsorption isotherm (R～2>0.99) .Kinetic studies showed that the adsorption process was found to follow pseudo-first-order and pseudo-second-order kinetics equation (R～2>0.99) .