Detoxification of Cr(VI) from Tannery Effluents by Natural Adsorbents

Abstract

Researches aimed at remedying our environment from unwanted pollutants have been on the increase with the hope of finding cost effective and efficient methods to replace the existing expensive ones. In this work three natural adsorbents; maize (Zea mays) cob, hardwood sawdust from Khaya senegalensis and coal (letter coded MC, SD and CO respectively) were tested for the detoxification of chromium from tannery effluents. Sorption experiments were carried out using static adsorption process in which changes in concentration of the adsorbate were monitored by the use of Shimadzu AA650 Double Beam Atomic Absorption/Flame spectrophotometer. Results indicated a wider applicability of MC with % removal of the adsorbate varying from 53.8% to 20% in the five different effluents analysed. While CO showed a promising performance of 76.9% to 40% between three effluent samples analysed. However, it shows no effects in the remaining two effluent samples. SD was found to be having least performance in the detoxification of the effluents analysed compared to MC and CO. This suggested that the adsorbents can be employed for the detoxification depending on the applicability needs.