Adsorptive removal of Cd²⁺ ions using dolochar at an industrial-scale process optimization by response surface...

In this work, performance of laboratory-synthesized dolochar has been investigated for adsorption of Cd²⁺ ions in a large-scale process with the application of Aspen Adsorption. Moreover, the optimum values of the operating parameters (namely, flow rate, bed height, and inlet metal ion concentration) that would result into maximum amount of cadmium ion adsorption (high exhaustion capacity) in minimum time (less exhaustion time) for a fixed mass of dolochar have been calculated via the application of response surface methodology. It was found that, at optimum values of bed height (3.48 m), flow rate (76.31 m³/day), and inlet concentration (10 ppm), the optimized value of exhaustion capacity and exhaustion time for cadmium ion adsorption in dolochar packed bed is equal to 1.85 mg/g and 11.39 h, respectively. The validity of these simulation experiments can be proven by the fact that the obtained exhaustion capacity of dolochar packed bed always remained in close proximity of the experimentally obtained value of adsorption capacity of the dolochar in batch process mode (equal to 2.1 mg/g).