REMOVAL OF Cr, Nr FROM PLATING WASTEWATER BY ADSORPTION USING RISE HUSKS

Abstract

Study on removing Cr, Ni in plating wastewater by adsorption method with adsorbent materials made from rice husks that activated by H2SO4 at laboratory scale. The results showed that adsorption efficiency reached the highest 82.8% of Cr and 90.7% of Ni under operating conditions: Cr, Ni concentrations were 35.73 mg/L and 54.27 mg/L respectively, pH 6, adsorption time was optimal 60 minutes and adsorbent dose was 3 g/50 mL. The relationship between amount of adsorbed on the adsorbent with the concentration of Cr, Ni in equilibrium was properly expressed through the Langmuir isothermal equation with the maximum adsorption capacity for Cr was 0.598 mg/g and Ni was 0.835 mg/g. Although the concentration of Cr, Ni after treatment has not reached the level of QCVN 40: 2011/BTNMT, but the removal efficiency of the initial concentration of Ni, Cr more than 80% has shown that it can handle a significant amount of Ni, Cr is initially treated by adsorption method.