2 results found.
European Journal of Sustainable Development Research, 2022, 6(1), em0173, https://doi.org/10.21601/ejosdr/11377
ABSTRACT: Biomass is a source of low-cost adsorbents used in the removal of contaminants. In this study, shells from an indigenous tree in Southern Africa called Morula were pyrolyzed to produce biochar that was used to sequester heavy metals from coal wash water. The produced biochar was activated using hydrochloric acid (HCl) and parameters such as the cation exchange capacity (CEC), point of zero charge (pHzc), elemental composition, mineral composition, proximate analysis and surface functional groups were determined. Batch adsorption experiments were carried out at 150 rpm for 60 min and 25 ºC at different metal ion concentrations and adsorbent dosages. The metal ions of interest were Zn, Ni and Fe and it was found that Fe recorded higher removals for both raw and activated biochar. Generally higher removals were noticed for both raw and activated at lower dosages (0.2 – 1.0 g/100 mL) and lower metal ion concentration (between 40 and 60 ppm) while lower removals were found at higher dosages (1 – 5 g/100 mL) and higher metal ion concentrations (between 400 – 600 ppm).
European Journal of Sustainable Development Research, 2019, 3(1), em0065, https://doi.org/10.20897/ejosdr/3917
ABSTRACT: The existing study demonstrates that water hyacinth (eichhorniacrassipes) is a potential adsorbent for the removal of Congo red dye from synthetic wastewater by batch process. The experiments were conducted to study the influence of various parameters such as initial dye concentration, pH, contact time and adsorbent dosage at different operating conditions. The effect of pH and dye concentration was found to be significant and the maximum removal was detected at pH 5 and concentration 100 ppm; considered to be optimum values. The removal of Congo red was consistent initially proportional to the adsorbent dosage. The adsorption process followed Langmuir adsorption isotherm model; point out that the process supported monolayer adsorption of Congo red on the adsorbent surface. Adsorption kinetics closely followed the pseudo-second-order model and mass transfer analysis indicated better transportation of adsorbate from solution phase to solid phase. These results point out suitability of the locally available low cost adsorbents in the niche area of wastewater treatment and can be implemented in commercial dye enriched industrial effluent.