Pretreatment of simulated tannery wastewaters by sonication with nanoscale iron particles

Abstract

Radiation processes (RP) have emerged as innovative ultimate treatment technologies for water and wastewater remediation. The advantage over conventional processes is due to their capacity to convert pollutants to simple elemental constituents without transferring them to another phase, as is the case in stripping, precipitation and carbon filtration. Recent research has shown that Nanoscale particles have been demonstrated to be very effective for the transformation and detoxification of a wide variety of common environmental contaminants. The purpose of this research was to investigate treatability of chromium (III) by adsorption on nanoscale ironparticles and the enhancement in the process by sonication of the solution. Selection of Cr(III) was based on the fact that itis the major pollutant in tannery wastewater and very toxic. Experiments with nanoparticles to assess the adsortive properties of the chronium followed by combined processes involving the particles and ultrasound. All those experiments were run to investigate the impacts of operational parameters such as adsorbent concentration, pH and contact time. It was found that the rate of destruction of the chromium by adsorption and ultrasound followed pseudo-first order kinetics. The results has shown that the use of ultrasound in presence of nanoparticles significantly enhanced the degradation duration. Overall, this study has demonstrated that chromium in tannery wastewaters may be effectively destroyed by use of optimized hybrid processess involving ultrasound and nanoparticles.