Hui Zhou Yan Fang Feng Yong Hong Wu Lin Zhang Yang.Mung Bean Shell (Vigna radiata L. Wilczek) - A Novel Cost-Effective Adsorbent for Removing Methylene Blue from Aqueous Solutions. Advanced Materials Research 2012 573-574: 68-79.

Abstract

The aim of this study was to establish an economical and environmentally benign biosorbent for removing synthetic dyes (e.g. methylene blue MB) from wastewater. The adsorption process of MB onto abandoned mung bean (Vigna radiata L. Wilczek) shell (MBS) was investigated in a batch system. The results showed that a wide range of pH (3.74 to 9.78) was favorable for the adsorption of MB onto MBS. Equilibrium studies indicated that the Langmuir model displayed the best fit for the isothermal adsorption data. The maximum monolayer adsorption capacity (165.92 mg g-1) calculated by the Langmuir equation was higher than that of many previously investigated low-cost bioadsorbents (e.g. peanut hull wheat straw etc.). The adsorption process best fitted pseudo-second-order kinetic model. Thermodynamic studies showed that the adsorption process was spontaneously exothermic and was mainly a physisorption. This study indicates that MBS is a promising unconventional affordable and environmentally friendly bio-measure that is easily deployed for removing cationic dyes from wastewater.