Work

Hydroxyapatite-activated seaweed biochar for enhanced remediation of fluoride contaminated soil at various pH ranges

Year: 2022

Type: article

Abstract: This study investigated the defluoridation efficiency of hydroxyapatite-activated seaweed (Eucheuma Cottonii) biochar (HSB) at various soil pH ranges (3â-11) while monitoring the impact of contact time (30Â min - 2.5Â h), adsorbent dosage (0.1â-0.5 g) as well as the initial fluoride concentration and compare its performance to its respective seaweed biochar (SB). Activation of SB with the hydroxyapatite lead to a shift in its point-zero-charge (pHPZC) from 6 to 7.4 broadening its defluoridation pH range from a solitary 5 to amid 3 through 11. The fluoride adsorption mechanism was found to follow both Langmuir (R2Â =Â 0.956) and Freundlich (R2Â =Â 0.942) isotherm models with a maximum defluoridation capacity of 3.03 mg/g equivalent to the defluoridation efficiency of 79. This is accounted to the existence of soil ions, SB active sites, and the attached hydroxyapatite, as fluoride adsorption sites each exhibiting a dissimilar fluoride removal mechanism. Therefore, the HSB could be a promising adsorbent for fluoride removal in the fluoride contaminated agricultural soils of inclusive pH ranges.

Source: Environmental Advances

DOI: 10.1016/j.envadv.2022.100329

Authors: Ruth Lorivi Moirana, Josephine Mkunda, Revocatus Machunda, Marcos Paradelo, Kelvin Mtei

Institutions: Nelson Mandela African Institution of Science and Technology, Natural Resources Institute, University of Greenwich

Language: English

Topic: Fluoride Effects and Removal

Subfield: Water Science and Technology

Field: Environmental Science

Domain: Physical Sciences

SDGs: Clean water and sanitation, Responsible consumption and production

Open Access status: gold

Estimated APC paid: $1,750