Tuning Adsorption Capacity by Alkoxy Groups: A Study on Acetic Acid Adsorption on UiO-66 Analogues from Aqueous Solution

Abstract

A series of alkoxy groups are introduced to the UiO-66 structure to enhance its adsorption performance toward acetic acid in water. The adsorption kinetics, isotherm, thermodynamics, and regeneration of these adsorbents have been investigated, and the excellent adsorption capacity of n-propyloxy-substituted adsorbent (UiO-66-3) is illustrated. The adsorption of acetic acid on UiO-66-3 was a complex multistep process, and the close contact between O of the ether bond of the adsorbent and H of the carboxyl group of acetic acid played an important role in adsorption. The kinetic results could be fitted well to the pseudo-second-order model. The adsorption isotherm followed the Langmuir isotherm, which indicated that the adsorption process involved a strong interaction between adsorbate and adsorbent. The thermodynamic parameters (ΔG, ΔH, and ΔS) had also been calculated, which verified that acetic acid adsorption on UiO-66-3 was a spontaneously endothermic process. The adsorbent exhibited good stability under specified experimental conditions, which consolidated its potential as a solution to wastewater containing dilute acetic acid.

Efficient removal of acetic acid by a regenerable resin-based spherical activated carbon

“…At present, a variety of adsorbents have been reported for acetic acid. Xianghai Guo et al used different kinds of water-tolerable metal-organic frameworks to systematically study the adsorptive activities for dilute acetic acid solutions, like MIL-derived and UiO-66-derived materials (Zhang et al 2016;Yu et al 2019). However, the high cost, the difficulty in large-scale industrial production, poor thermal and chemical stability make MOFs materials have many restrictions on industrial application.…”

Synthesis and Application of Ion-Exchange Magnetic Microspheres for Deep Removal of Trace Acetic Acid from DMAC Waste Liquid

“…In recent years, some studies have been published on the adsorption of acetic acid. Guo and Chen’s research group reported a method of using MOF material UiO-66 to adsorb acetic acid in an aqueous solution [ 4 , 5 , 6 ]. Yang et al prepared an alkaline site-modified MgO for the selective adsorption of the CH 3 COOH/C 6 H 6 binary mixture, and their results show the highest selectivity [ 7 ].…”