Tio2 and carbon nanotubes composites modify capacitive deionization anodes to improve the dechlorination efficiency in desulfurization wastewater

Abstract

A new capacitive deionization (CDI) technology was used to remove Cl− from desulfurization wastewater. TiO2 and carbon nanotubes (CNTs) were combined with N-methyl pyrrolidone (NMP) to form composites by solvothermal method which is coated onto the CDI anode to improve the dechlorination efficiency (DE). The morphology, surface area, wettability, crystal structure and chemical composition of the TiO2/CNTs were characterized. It showed good hydrophilicity (contact angle: 85.9°), high specific surface area (96.68 m²/g) and high specific capacitance (87.6 F/g). The experimental results illustrated that the best DE was achieved by the composites (60%T/C) under 1.2 V with the maximum electrosorption capacity toward 6.5 mg/g, and the TiO2/CNTs composites have excellent stability. The adsorption kinetics analysis was explored and analyzed. Furthermore, TiO2/CNTs composites exhibit excellent DE in actual desulfurization wastewater. The catalysis and adsorption mechanisms of TiO2/CNTs anode were discussed in detail. This study provides a new direction for the application of TiO2/CNTs composites as adsorption materials of CDI in the Cl− of desulfurization wastewater.

Enhanced adsorption behavior of U(VI) using PZSC/ZnO ceramic composite derived from polyphosphazene

“…On the other hand, the addition of metal oxides (such as Fe 2 O 3 , MgO, Al 2 O 3 , and ZnO) to the carbon substrates can significantly alter the physicochemical properties, such as wettability, specific surface area, and zeta potential, which favors the adsorption behavior. 26,27 ZnO has received extensive attention as an adsorbent for water pollution on account of its unique properties, mild reaction conditions, and low price. 28 Large amounts of polar sites exist on the surface of ZnO, which can form hydroxyl groups (−OH) in aqueous solution and facilitate the combination of ZnO with metal ions.…”