Adsorption of Zn(Ⅱ) from wastewater by sulfhydryl rice husk carbon

Removal of zinc ions from the wastewater by mercapto acetic acid modified rice husk carbon was studied. The effects of pH, reaction temperature and time, and desorption on the adsorption effect of thiol based rice husk carbon were studied. Scanning electron microscopy and X ray energy spectrum analysis of modified materials were carried out. The results showed that the surface of modified rice husk carbon was more smooth and porous, and the surface functional group —SH content increased by the chemical modification to rice husk carbon, and the adsorption capacity of Zn(Ⅱ) was improved. The modified rice husk carbon has a wide range of pH (6-8), and the adsorption equilibrium is reached at 300 min at 25 ℃. The adsorption process conforms to the pseudo two kinetic equation and is an endothermic reaction. According to the activation energy calculation by Arrhenius empirical equation, the adsorption belongs to active chemical adsorption. Based on the Langmuir adsorption isotherm equation, the theoretical saturated adsorption capacity of the thiol rice husk carbon to Zn(Ⅱ) is 11.26 mg∕g. When combined with desorption, it is known that the adsorbent has good immobilization on Zn(Ⅱ) and has certain adsorption effect.