Snail Shells as Sustainable Remediation Agents: A Novel Approach to Removing Heavy Metals from Produced Water in the Oil and Gas Industry

Abstract

Abstract Global environmental standards mandate Oil and Gas producers to treat Produced Water (PW) before disposal. This can pose an economic conundrum as PW's low economic value does not justify the high cost of treatment. This study explores the use of the adsorption capabilities of Achatina fulica snail shell particles in eliminating heavy metal contaminants from PW thus providing a better alternative without compromising industry standards. Through comprehensive optimization using response surface methodology and central composite design, various adsorption parameters such as temperature, adsorbent dosage, contact time, pH, and lead concentration were examined on wastewater samples. Lead nitrate content was measured as a heavy metal contaminant. The snail shell adsorbent underwent thorough characterization employing Scanning Electron Microscope (SEM), Energy- Disperse X-ray (EDX) analyses, and Fourier Transform Infra-Red Spectroscopy (FTIR). Atomic Absorption Spectrophotometry was employed for heavy metal analysis. Response Surface Methodology was employed to evaluate the adsorption of lead (II) ions on the bioadsorbent. The snail shell bioadsorbent exhibited a composition rich in various organic compounds and results indicated that lead ion removal positively correlated with increasing lead concentration and pH, inversely correlated with escalating snail shell dosage, and exhibited a slight decrease with contact time. Furthermore, optimal conditions for achieving a 99.3167% adsorption percentage of lead ions were identified. This study underscores the sustainable nature and efficacy of snail shells as a remarkable adsorbent for mitigating heavy metal contamination, particularly relevant to the challenges posed by heavy metal contamination in produced water in the oil and gas industry.