Oxidant-Free Thiol–Ene Grafting of Granular Activated Carbon for Mercury(II) Adsorption from Aqueous Solution and Synthetic Gas Condensate

@article{saengsrichan2026oxidantfree,
  title = {{Oxidant-Free Thiol–Ene Grafting of Granular Activated Carbon for Mercury(II) Adsorption from Aqueous Solution and Synthetic Gas Condensate}},
  author = {Aphinan Saengsrichan and Jakkapop Phanthasri and Supawadee Namuangruk and Poobodin Mano and Suttipong Wannapaiboon and Doan Pham Minh and Sanchai Kuboon and Saran Youngjan and Teera Butburee and Issaraporn Rakngam and Panot Krukkratoke and Gopinathan Sankar and Nurak Grisdanurak and Suthirat Kittpongvises and Rattabal Khunphonoi and Pongtanawat Khemthong and Pummarin Khamdahsag},
  journal = {ACS Omega},
  year = {2026},
  month = oct,
  doi = {10.1021/acsomega.6c09402},
  url = {https://pubs.acs.org/acsodf/article/doi/10.1021/acsomega.6c09402/5458080/Oxidant-Free-Thiol-Ene-Grafting-of-Granular},
  note = {CC BY 4.0},
}

TY  - JOUR
TI  - Oxidant-Free Thiol–Ene Grafting of Granular Activated Carbon for Mercury(II) Adsorption from Aqueous Solution and Synthetic Gas Condensate
AU  - Aphinan Saengsrichan
AU  - Jakkapop Phanthasri
AU  - Supawadee Namuangruk
AU  - Poobodin Mano
AU  - Suttipong Wannapaiboon
AU  - Doan Pham Minh
AU  - Sanchai Kuboon
AU  - Saran Youngjan
AU  - Teera Butburee
AU  - Issaraporn Rakngam
AU  - Panot Krukkratoke
AU  - Gopinathan Sankar
AU  - Nurak Grisdanurak
AU  - Suthirat Kittpongvises
AU  - Rattabal Khunphonoi
AU  - Pongtanawat Khemthong
AU  - Pummarin Khamdahsag
PY  - 2026
DA  - 2026/10/26
JO  - ACS Omega
DO  - 10.1021/acsomega.6c09402
UR  - https://pubs.acs.org/acsodf/article/doi/10.1021/acsomega.6c09402/5458080/Oxidant-Free-Thiol-Ene-Grafting-of-Granular
AB  - Mercury removal from aqueous and hydrocarbon media requires sorbents that combine strong binding affinity with sufficient pore accessibility and mass transfer. In this study, granular activated carbon (GAC) was treated with 1,2-ethanedithiol through an oxidant-free, thermally initiated thiol–ene-type radical route to produce sulfur-functionalized GAC (S-GAC) with different sulfur loadings. The sulfur content increased from 3.38 to 15.07 wt %, while the BET specific surface area decreased from 859 to 25 m2 g–1, indicating progressive pore occupation and blockage. At low initial Hg(II) concentration, sulfur functionalization enhanced Hg(II) removal in both aqueous solution and synthetic gas condensate, with 10–30%S-GAC achieving very low residual Hg(II) concentrations. At elevated aqueous Hg(II) concentrations, pristine GAC exhibited faster initial uptake and approached a plateau earlier, whereas S-GAC showed slower but sustained adsorption. At approximately 40 mg L–1 Hg(II) concentration, 5%S-GAC and 10%S-GAC ultimately achieved slightly higher observed uptakes than pristine GAC, while at approximately 120 mg L–1 pristine GAC retained the highest uptake over the monitored period. These results show that the effect of sulfur functionalization depends on Hg(II) loading, contact time, and the balance between Hg–S affinity and pore accessibility. XPS, Hg L3-edge XAS, and DFT calculations were consistent with sulfur-containing Hg coordination environments and more favorable interaction near sulfur-rich edge configurations. Sulfur functionalities remained strongly retained over pH 2–10, although regeneration performance decreased with repeated cycles. Overall, Hg(II) capture reflects the combined effects of sulfur-site affinity, pore accessibility, mass transfer, Hg(II) loading, and the treatment matrix.
SN  - 2470-1343
ER  -