Kinetic modeling of sorption–desorption cycles for phenol removal with a cyclodextrin polymer

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) 2019, 75(0), , pp.93-99
• Main Authors: Peñas, Francisco J., Romo, Ana, Isasi, José R., San José, María J., Alvarez, Sonia
• Format: Article
• Language: English
• Subjects: Breakthrough curve; Cyclodextrin polymer; Elution curve; Kinetic modeling; Mass-transfer coefficient; Sorption–desorption cycles; 화학공학
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2019.03.002

•Phenol adsorption in cyclodextrin polymers and regeneration with short-chain alcohols.•Breakthrough curves very well described by a two-parameter dose–response model.•Elution curves fit well to a pulse-peak equation with two free parameters.•Methanol better regenerant in long-term application of beds of cyclodextrin hydrogels.•Average and local mass-transfer coefficients calculated from breakthrough curve model. This paper examines the long-term application of a cyclodextrin hydrogel sorbent in multiple sorption–desorption cycles. Aqueous phenol was the target pollutant, whilst methanol, ethanol and isopropanol were chosen as eluents. The experimental results were well described by empirical models: the breakthrough curves by a two-parameter dose–response equation, and the elution curves by a pulse-peak equation with two independent parameters. The differences in polarity of solvents produced sorbent fragmentation, particularly marked for isopropanol and considerably lower for methanol, and therefore a progressive increase in mass-transfer coefficients. In addition, a dual approach was developed from the proposed breakthrough model to address the mass transport of sorbate within the packed beds. The first one defines an average mass-transfer coefficient as representative for each complete sorption cycle, whereas a time-profile of this coefficient is deduced in the second method. A sorption capacity of 29.6 mg-phenol/g-sorbent was found in the working conditions.