Experimental and modeling of competitive biosorption of benzene, toluene, ethylbenzene, xylenes, and naphthalene (BTEXN) in a packed-bed column with a macroalgae-based composite: Effect of dissolved organic matter and flow rate on breakthrough curves

Abstract

Abstract This study aimed to investigate the adsorption performance of a macroalgae-based biocomposite as a biosorbent of water-soluble hydrocarbons (WSH) like BTEXN (benzene, toluene, ethylbenzene, xylenes, and naphthalene) on packed bed columns. The effects of the inlet flow rate (0.3–1.1 mL/min), using naphthalene as a model, were analyzed and the operation parameters are described. The registered breakthrough volume increased from 12 to 52 mL at an EBCT of 4 and 20 min, respectively. The breakthrough curves profiles of the competitive biosorption of BTEXN were modeled by five well-accepted dynamic adsorption models known as Thomas, Clark, Dose-Response, BDST, and Yoon-Nelson. The biocomposite swelling degree and the external mass transfer limitations are the main factors influencing the adsorption process at different inlet fluxes, a result that was corroborated by the linearized Yoon-Nelson model. In the case of multicomponent systems, the hydrocarbon hydrophobicity determined the composite selectivity (N > X > E > T > B), with breakthrough volume values from 7.51 to 14.33 mL for natural water, and from 12.14 to 28.66 mL for deionized water. Finally, the evaluated biocomposite showed to be adequate for the continuous biosorption of water-soluble hydrocarbons.