Removal of 2-fluoro and 2-iodophenol from aqueous solutions using industrial wastes.

A comparative study of the adsorbents prepared from several industrial wastes for the removal of 2-fluorophenol and 2-iodophenol has been carried out. The results show that maximum adsorption on carbonaceous adsorbent prepared from fertilizer industry waste has been found to be 35.3 and 235.3 mg g(-1) for 2-fluorophenol and 2-iodophenol, respectively. Compared to carbonaceous adsorbent, the other three adsorbents (viz., blast furnace sludge, dust, and slag) adsorb phenols to a much smaller extent. This has been attributed to the carbonaceous adsorbent having a larger porosity and consequently higher surface area. The adsorption of phenols on this adsorbent has been studied as a function of contact time, concentration and temperature. The adsorption has been found to be endothermic, and the data conform to the Langmuir equation. The further analysis of data indicates that adsorption is a first order process and pore diffusion controlled. A comparative study of adsorption results with those obtained on standard activated charcoal sample shows that prepared adsorbent is about 45% as efficient as standard activated charcoal and therefore, can be fruitfully employed for the removal of phenolic pollutants from wastewaters.