Novel iron-supported ZSM-5 molecular sieve remove arsenic from wastewater by heterogeneous nucleation with pH limit breaking. (August 2022)

• Record Type: Journal Article
• Authors: Li, Guohua; Qi, Xianjin; Yang, Nina; Duan, Xiaoxu; Zhang, Aimin
• Is Part Of: Chemosphere. Volume 301(2022)
• Publication Date: 2022-08
• Subjects: ZSM-5/Fe adsorbent -- Arsenic -- Industrial wastewater -- Heterogeneous nucleation adsorption; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2022.134676
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Molecular sieves have also been used for arsenic adsorption in recent years because of their special structure. In order to solve the problem of arsenic pollution in drinking water and/or industrial wastewater, ZSM-5/Fe adsorbent was prepared by loading iron on ZSM-5 molecular sieve. It is also used as an excellent adsorbent for removing arsenic and other heavy metal ions from industrial wastewater. At room temperature, the concentration of arsenic was reduced from 100 mg/L to 0.006 mg/L after the solution pH was adjusted to the range of weak acid to weak base (4–10) and 0.5 g of ZSM-5/Fe adsorbent was added for reacting 2 h. The adsorption capacity reached 40.00 mg/g, the adsorption efficiency reached 99.99%, reaching the national standard of drinking water. Adsorption thermodynamics, kinetics and isotherms showed that the adsorption mechanism of arsenic is heterogeneous nucleation adsorption (including electrostatic attraction and chemical precipitation). Moreover, ZSM-5/Fe adsorbent can adjust pH spontaneously by using non-skeleton Si–Al phase to achieve effective adsorption from weak acid to weak base. At the same time, ZSM-5/Fe adsorbent showed good reusability and stability in five cycles. This study provides an important idea for the application of ZSM-5 molecular sieve in many fields and the efficient removal of arsenic from drinking water and industrial wastewater. Graphical abstract: Image 1 Highlights: A new adsorbent material ZSM-5/Fe was prepared for drinking water and industrial wastewater. The adsorption mechanism is heterogeneous nucleation adsorption. High adsorption capacities were noticed in the pH range from weak acid to weak base.