Fixed-Bed Adsorption Performance And Empirical Modeling Of Cadmium Removal Using Adsorbent Prepared From The Cyanobacterium Aphanothece Sp Cultivar

Water contamination by cadmium (Cd), which is a toxic heavy metal widely used in many industrial processes, is a pervasive environmental problem. This study investigated the removal of Cd by dry cyanobacterium Aphanothece sp cultivar in adsorption columns The effect of inlet Cd concentrations (1.00 - 4.85mg/L), flow rates (0.30-0.60 L/h) and bed height (4.6 -7.2 cm) on the breakthrough characteristics of the adsorption column was investigated. The maximum adsorption capacity and efficiency were found to be 8.20 mg/g and 89.07 %, respectively with a flow rate of 0.60 1411 and 4.85 mg/L inlet concentration of Cd. The fixed bed adsorption data were fitted to three well known fixed bed empirical models namely Thomas, Adam-Bohart and Yoon-Nelson. The experimental results well fitted with the models mentioned above with R-2 of greater than 0.98 at different conditions. The regeneration efficiency of benthic cyanobacterium Aphanothece sp cultivar based adsorbent was studied using 0.1 M HCl. Repetitive adsorption-regeneration experiment show that, at the end of the fifth cycle, the desorption efficiency decreased by 21%. Thus, further research is necessary to improve the reusability of dried biomass of cyanobacterium Aphanothece sp adsorbent. (C) 2020 Elsevier B.V. All rights reserved.