Adsorption performance of methylene blue on modified coal gangue

The alkali heat modification used in coal gangue. And the adsorption effect of MB on original gangue and modified gangue were observed. The results were showed that removal rate of MB was 96.87% and 45.45% by modified gangue and original gangue under the conditions of MB initial concentration 50mg.L-1. The adsorption mechanism was discussed based on Freundlich isotherm model and Langmuir isotherm model. It was proved that MB was easy to be adsorbed by modified coal gangue and the adsorption was belong to monolayer adsorption.The pseudo-second-order kinetic model was best accord to adsorption. And the rate of absorption was control by intra-particle diffusion.