Adsorption performance and mechanism of Arsenic(III) and Arsenic(V) by using copper-manganese binary oxide

ABSTRACT

Arsenic contamination threatens the safety of drinking water in many areas of the world. As(V) is less toxic and easier to remove than As(III). Hence, it is essential to oxidise As(III) to As(V). Based on the previous studies, Cu-Mn binary oxide (CMBO) (with a molar ratio of Cu/Mn = 3:1) was prepared by a two-step method. The results showed that CMBO has a large specific surface area (67.74 m²/g) and pore size (16.87 nm). Moreover, CMBO has an inconspicuous crystal structure and abundant hydroxyl groups, which are favourable for arsenic adsorption. The adsorption kinetics results indicated that As(III) was oxidised to As(V) during the adsorption process, and the adsorption rate for As(V) removal was faster than that for As(III) removal. The saturated adsorption capacities of As(III) and As(V) were calculated to be 64.17 mg/g and 84.87 mg/g via the Langmuir isotherm model, respectively. The results of the pH effect studies indicated that acidic conditions promoted the removal of both As(III) and As(V) by CMBO due to the electrostatic attraction. The spectroscopic analysis results demonstrated that Mn oxides within CMBO played a vital role in As(III) oxidation. The removal of As(III) by CMBO was attributed to the synergistic effect of As(III) oxidation by Mn oxides and As sorption by Cu oxides. Overall, CMBO is a promising sorbent with great potential for removing arsenic.

KEYWORDS:

• Mn oxides
• Cu oxides
• adsorption
• arsenite
• oxidation

Author contributions

All authors contributed to the study’s conception and design. Material preparation, data collection, and analysis were performed by Taotao Dai, Hang Lei, Birong Miao, and Jiayou Zhong. The first draft of the manuscript was written by Xuan Sun, Kun Wu, and Ting Liu. All authors commented on previous versions of the manuscript. All authors read and approved the final manuscript

Ethical standards

The work described here is original research that has not been published previously. All authors listed have made substantial contributions to the manuscript. All authors listed have approved and agree to submit the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data will be provided if required.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/03067319.2024.2346189

Additional information

Funding

This work was financially supported by the Key Research and Development Project of Shaanxi Province, China #1 under Grant [number 2019ZDLSF05-03/2021ZDLSF05-06]; the Research Project of Jiangxi Provincial Department of Water Resources #2 under Grant [number 202325ZDKT09]; the Open Fund of Jiangxi Provincial Key Laboratory of Water Resources and Environment of Poyang Lake, Jiangxi Academy of Water Science and Engineering #3 under Grant [number 2021SKSH 04]; and the Research on Key Technologies of Sponge Demonstration City Construction of Changzhi #4 under Grant [number 1404992022CGK00545].