Selective adsorption mechanisms of iodinated trihalomethanes onto thiol-functionalized HKUST-1s in a mixed solute

Phacharapol Induvesa; Chalita Ratanatawanate; Aunnop Wongrueng; Patiparn Punyapalakul

doi:10.1016/j.jenvman.2022.115099

Selective adsorption mechanisms of iodinated trihalomethanes onto thiol-functionalized HKUST-1s in a mixed solute

J Environ Manage. 2022 Aug 1:315:115099. doi: 10.1016/j.jenvman.2022.115099. Epub 2022 Apr 29.

Authors

Phacharapol Induvesa¹, Chalita Ratanatawanate², Aunnop Wongrueng³, Patiparn Punyapalakul⁴

Affiliations

¹ International Postgraduate Programs in Hazardous Substance and Environmental Management, Graduate School, Chulalongkorn University, Bangkok, 10330, Thailand; Center of Excellence on Hazardous Substance Management, Chulalongkorn University, Bangkok, 10330, Thailand.
² National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, 12120, Thailand; Research Network of NANOTEC - CU on Environment, Bangkok, 10330, Thailand.
³ Department of Environmental Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai, 50200, Thailand.
⁴ Center of Excellence on Hazardous Substance Management, Chulalongkorn University, Bangkok, 10330, Thailand; Department of Environmental Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand; Research Unit Control of Emerging Micropollutants in Environment, Chulalongkorn University, Bangkok, 10330, Thailand; Research Network of NANOTEC - CU on Environment, Bangkok, 10330, Thailand. Electronic address: patiparn.p@chula.ac.th.

PMID: 35500481
DOI: 10.1016/j.jenvman.2022.115099

Abstract

The selective adsorption mechanisms involved in the competitive adsorption of five iodinated trihalomethanes (I-THMs) onto dithiolglycol and (3-mercaptopropyl)-trimethoxy functionalized HKUST-1 (HK-SH and HK-MPTS, respectively) were investigated by single- and mixed-batch adsorption. HK-SH had the highest adsorption rates and capacities for the five I-THMs, followed by HK-MPTS and pristine HKUST-1, even though the porosity and surface area decreased after modification. The primary adsorptive mechanism of HK-SH consists of ion-dipole interactions of I-THMs with the protonated hydroxyl and thiol groups at the metal (Cu) node, which is supported by Lewis acid-base reactions via Cu-Cu complex and π-π interactions. In a mixed solute, bromodiiodomethane, which was the most hydrophobic and had the smallest molecular size, exhibited the most competitive adsorption on HK-SH. In contrast, the selective adsorption of I-THMs onto HK-MPTS was affected by their log K_ow values, causing hydrophobic partitioning onto the alkyl chain of the mercaptopropyl group. Iodinated haloforms tend to achieve a higher adsorption rate and capacity than chlorinated and brominated haloforms via hydrophobic partitioning. Moreover, dithiolglycol grafted onto HK-SH can better promote the excellent selective adsorption performance of iodoacetamide than dichloroiodomethane and iodoacetic acid in both single- and mixed-solute solutions due to hydrogen bonding via the -NH₂ group of diiodoacetamide.

Keywords: HKUST-1; Iodinated DBPs; Iodinated trihalomethane; Selective adsorption mechanism; Thiol functionalization.

MeSH terms

Adsorption
Metal-Organic Frameworks
Solutions
Sulfhydryl Compounds
Trihalomethanes
Water Pollutants, Chemical* / chemistry
Water Purification*

Substances

Metal-Organic Frameworks
Solutions
Sulfhydryl Compounds
Trihalomethanes
Water Pollutants, Chemical
bis(1,3,5-benzenetricarboxylate)tricopper(II)