Facile synthesis and application of Fe(NO3)3.9H2O modified walnut biochar for antimony removal from groundwater

Title : Facile synthesis and application of Fe(NO3)3.9H2O modified walnut biochar for antimony removal from groundwater

Abstract:

This study focuses on synthesizing Iron nitrate nonahydrate-modified walnut biochar (Fe-BC) to remove Sb(III) from groundwater. Batch experiments were conducted to investigate the effects of pH, initial concentration, contact time, and minerals in groundwater on Sb(III) removal. The Sb(III) removal rate reached 99.5% by increasing the Fe-BC dose from 0.1 to 5 mg/L and followed pseudo first order kinetics model. The removal data fitted well with the Freundlich and Sips model indicating that the adsorption of Sb(III) onto Fe-BC was not limited to monolayer adsorption. Sb(III) removal% was consistent over the pH range of 4-10 which is the typical range for actual groundwater, which shows that the adsorbent is not pH specific. Coexisting ions such as Na⁺, NO ^-, Ca²⁺, and Mg²⁺ in groundwater enhance the adsorption of Sb(III) by the Fe-BC adsorbent. The presence of K⁺ and As³⁺ doesn’t affect the Sb removal. On the other hand, HCO3- demonstrates noticeable interference in the removal of Sb(III) due to its chemical resemblance to Sb(OH)6- and Sb(OH)3 but this interference is not expected to severely restrict the practical application of the adsorbent. SEM-EDX, X-ray diffraction and FTIR revealed that biochar modified with iron oxides had more active sites than virgin biochar. Based on the efficient adsorption capacity and low treatment cost, Fe-BC can be used as a promising adsorbent for antimony removal from groundwater

Biography:

Oneeba Tahir studied Chemistry at SBA School of Science, LUMS, Pakistan, and graduated with an MS in 2022. There, she worked in the Water Treatment Lab where she designed sustainable materials for applications in contaminant remediation. She then got a fully funded PhD position and Dean’s fellowship at the University of Nebraska-Lincoln and working in the research group of Prof. Stephen Morin at the Department of Chemistry, UNL. She is a Graduate Lab Assistant at the same institution and her research focuses on repurposed materials and adaptive surfaces.