Co‐adsorption of Trichloroethylene and Arsenate by Iron‐Impregnated Granular Activated Carbon

Abstract

Co-adsorption of trichloroethylene (TCE) and arsenate [As(V)] was investigated using modified granular activated carbons (GAC): untreated, sodium hypochlorite-treated (NaClO-GAC), and NaClO with iron-treated GAC (NaClO/Fe-GAC). Batch experiments of single- [TCE or As(V)] and binary- [TCE and As(V)] components solutions are evaluated through Langmuir and Freundlich isotherm models and adsorption kinetic tests. In the single-component system, the adsorption capacity of As(V) was increased by the NaClO-GAC and the NaClO/Fe-GAC. The untreated GAC showed a low adsorption capacity for As(V). Adsorption of TCE by the NaClO/Fe-GAC was maximized, with an increased Freundlich constant. Removal of TCE in the binary-component system was decreased 15% by the untreated GAC, and NaClO- and NaClO/Fe-GAC showed similar efficiency to the single-component system because of the different chemical status of the GAC surfaces. Results of the adsorption isotherms of As(V) in the binary-component system were similar to adsorption isotherms of the single-component system. The adsorption affinities of single- and binary-component systems corresponded with electron transfer, competitive adsorption, and physicochemical properties.

Evaluation of absorption efficiency of Zeolite ZSM-5 in the removal of styrene vapors

“…Furthermore, the absorption capacity of toluene on both types of activated carbon and in all the tested conditions was higher than the absorption capacity of benzene (27). Lilo-Roudnas et al conducted a study to investigate the effects of competitive adsorption of benzene-toluene composition with a concentration of 200 ppm on 8 different samples of activated carbon (26). They reached similar results.…”

“…In this study, with increase in the absorption bed depth, the absorption capacity of zeolite increased; however, with increase in air flow rate and inlet concentration, the absorption capacity decreased. In another study, the researchers investigated benzene absorption on two types of activated carbon; the first type was prepared from the wood composites cutting dust and the second type was a commercially supplied activated carbon prepared from coconut shell (26). Asilian et al reported that in the sampling of benzene as a VOC in ambient air by clinoptilolite zeolite, the mesh number of 80/60 compared to the mesh number of 60/40 has longer breakthrough time (27).…”

Carbon Nanotube Based Groundwater Remediation: The Case of Trichloroethylene

“…Approaches for removal, degradation and detection of TCE have commonly included activated carbon [15,16,17,18,19,20,21,22,23] as a host and adsorbent. Even though activated carbon and naturally sourced materials such as pine needle biochar [24,25] have orders of magnitude advantages in cost, the use of two-dimensional carbon based materials (graphene nanosheets, graphene oxides and various carbon nanotubes (CNTs) with different chiralities) offers specificity in adsorption and remediation with relatively lower % loading in membranes and composites.…”