Sustainable utilization of water treatment residue as a porous geopolymer for iron and manganese removals from groundwater

Pumipat K Pachana; Ubolluk Rattanasak; Kamchai Nuithitikul; Peerapong Jitsangiam; Prinya Chindaprasirt

doi:10.1016/j.jenvman.2021.114036

Sustainable utilization of water treatment residue as a porous geopolymer for iron and manganese removals from groundwater

J Environ Manage. 2022 Jan 15;302(Pt A):114036. doi: 10.1016/j.jenvman.2021.114036. Epub 2021 Nov 1.

Authors

Pumipat K Pachana¹, Ubolluk Rattanasak², Kamchai Nuithitikul³, Peerapong Jitsangiam⁴, Prinya Chindaprasirt⁵

Affiliations

¹ Department of Chemistry, Faculty of Science, Burapha University, Chonburi, 20131, Thailand; Center of Excellence on Environmental Health and Toxicology (EHT), Faculty of Science, Burapha University, Chonburi, 20131, Thailand.
² Department of Chemistry, Faculty of Science, Burapha University, Chonburi, 20131, Thailand; Center of Excellence on Environmental Health and Toxicology (EHT), Faculty of Science, Burapha University, Chonburi, 20131, Thailand. Electronic address: ubolluk@go.buu.ac.th.
³ Biomass and Oil Palm Center of Excellence, School of Engineering and Technology, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
⁴ Center of Excellence in Natural Disaster Management, Department of Civil Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai, 50200, Thailand.
⁵ Sustainable Infrastructure Research and Development Center, Department of Civil Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen, 40002, Thailand; Academy of Science, The Royal Society of Thailand, Office of The Royal Society, Dusit, Bangkok, 10300, Thailand.

PMID: 34735831
DOI: 10.1016/j.jenvman.2021.114036

Abstract

Raw water is a significant resource for industrial water usage, but this water is not directly suitable for use due to the presence of contaminants. Therefore, pre-treatment is essential. The treatment generates water treatment residue (WTR) which consists of silt, clay and undesirable components. Most WTR is conventionally disposed of in landfill. In addition, the presence of iron (Fe) and manganese (Mn) in groundwater can result in a reddish-brown color and undesirable taste and odour. A number of expensive and complex technologies are being used for the removal of such iron and manganese. Due to the high Al₂O₃ and SiO₂ content in WTR, therefore, this research proposes the use of WTR as the source material for geopolymer production for Fe/Mn removal. With the availability of free alkali in the geopolymer framework, the OH^--releasing behavior of the WTR-based geopolymer was investigated by the precipitation of Fe(II) ion. The WTR-based geopolymer was calcined at 400 °C and 600 °C to obtain a strong geopolymer matrix with the ability to remove Fe/Mn ions. The results show that the WTR-based geopolymer has the potential to remove Fe from Fe-contaminated water. Hydroxide ions are released from the geopolymer and form an Fe(OH)₃ precipitate. Geopolymer with a calcination temperature of 400 °C provides total removal of the Fe after 24 h of immersion. In addition, the existence of Fe(OH)₃ helps to coprecipitate the Mn(OH)₂ in the Fe/Mn solution leading to a significant reduction of Mn from the solution. The pH value and retention time play an important role in the final metal concentration. The final pH of the solution is close to 8.5, which is the recommended value for boiler water. This method offers an alternative use of WTR in making a porous geopolymer for groundwater Fe/Mn removal using a simple method.

Keywords: Fe removal; Geopolymer; Hydroxide precipitation; Mn removal; Water treatment residual.

MeSH terms

Groundwater*
Ions
Iron / analysis
Manganese / analysis
Porosity
Silicon Dioxide
Water Purification*

Substances

Ions
Manganese
Silicon Dioxide
Iron