Adsorption of Benzene Vapor onto Activated Biomass from Cashew Nut Shell: Batch and Column Study

S.      Suresh; G.      Vijayalakshmi; B.      Rajmohan; V.      Subbaramaiah

Abstract

The preparation of chemically modified activated cashew nut shell (ACNSB) of different impregnation ratios and their effects in adsorption of benzene vapor were studied. Effects of chemical pre-impregnation using phosphoric acid at different ratios (1:1 and 2:1) were investigated in order to patent. Physico-chemical characterization including surface area, scanning electron microscopy, energy dispersive X-ray spectroscopy, High-resolution Transmission Electron Microscopy and Fourier transform infrared spectroscopy of the ACNSB before and after benzene adsorption have been done to understand the adsorption mechanism. Optimum conditions for benzene removal were found to be, adsorbent dose m=10 g/l of solution and time (t) 120 min for the C0 range of 300–500 mg/l. Adsorption of benzene followed pseudosecond- order kinetics. Langmuir and R–P isotherms were found to best represented data for benzene adsorption onto ACSNB. In ACNSB column experiments, it can be concluded that concentration of benzene increases with the longer breakthrough time and hence higher adsorption capacity. ACSNB are many advantages includes simple and fast, organic solvent recovery, economical, energy savings, environmentally safe aspect and minimize the waste management problem.

Keywords: Adsorption, Benzene, cashew nut shell, ACNSB, phosphoric acid, biofiltration, polymerization, phenolphthalein