Adsorptive removal of pharmaceutical contaminants: Accurate description of tailing breakthrough curves
Document Type
Article
Publication Date
10-1-2023
Abstract
Fixed bed adsorption is a well-established method used to remove various contaminants, including pharmaceuticals, from aqueous solutions. Mathematical modeling plays a pivotal role in analyzing the dynamic behavior of fixed bed adsorption processes. The classic Bohart-Adams model, dating back over a century, is commonly used to describe fixed bed breakthrough curves. However, it encounters difficulties in effectively interpreting tailing breakthrough curves resulting from the slow approach of the fixed bed to saturation. This study presents an enhanced version of the Bohart-Adams model, specifically tailored to address the challenge of analyzing tailing breakthrough data concerning pharmaceutical contaminant adsorption in fixed bed adsorbers. The new formulation incorporates a conceptual steric hindrance model, proposing that the tailing breakthrough behavior is a consequence of a reduction in the rate of adsorption as surface coverage increases. Through rigorous testing, the new model showcased superior performance compared to the original model, accurately describing the tailing breakthrough curves commonly observed with pharmaceutical contaminants such as diclofenac, sulfamethoxazole, and tetracycline. Additionally, comparative analyses of the new model, a mechanistic model, and the empirical Yan model conclusively demonstrated the superiority of the newly proposed approach. The new Bohart-Adams model can be used to precisely predict breakthrough and exhaustion times or optimize column operating conditions.
Keywords
Antibiotic, Asymmetric breakthrough curve, Hindered diffusion, Steric hindrance, Tailing breakthrough curve
Divisions
sch_che
Funders
None
Publication Title
Journal of Environmental Chemical Engineering
Volume
11
Issue
5
Publisher
Elsevier Science Ltd
Publisher Location
125 London Wall, London, ENGLAND