Marzhan S Kalmakhanova

M. Kh. Dulaty Taraz University, Kazakhstan

Title: Development and Evaluation of Sustainable Permeable Reactive Barriers Based on Natural Clays and Activated Carbon for Wastewater Treatment

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Biography

Kalmakhanova M.S. is associate professor at M.Kh. Dulaty Taraz University. Since her PhD studies in Chemistry, concluded in 2019 in collaboration with Bragança Polytechnic Institute, Portugal, she has continued involvement with environmental science research activities, specifically focused on the synthesis and characterization of adsorbents and catalysts to solve water environmental problems. She was awarded several prizes and recognitions, as best university teacher in 2022, supervised several projects, performed internships in Portugal, Spain and USA. Presented her work at international conferences in Spain, Greece, Japan, Check Republic, USA and Austria, and authored over 50 publications in scientific journals and conference proceedings. 

Abstract

Permeable reactive barriers (PRBs) are an effective in situ technology for the treatment of contaminated groundwater and wastewater, especially in areas influenced by industrial and municipal effluents. This study is focused on the development and experimental evaluation of sustainable PRBs based on natural clays and activated carbon derived from peanut shells for the removal of pharmaceutical contaminants from aqueous solutions.

Natural clays obtained from different deposits were characterized using physicochemical and structural techniques, including BET surface area analysis, FTIR spectroscopy, XRD, pHpzc determination, and elemental composition analysis. Activated carbon was synthesized from agricultural waste via chemical activation and thoroughly characterized to assess its surface properties and adsorption potential. Batch adsorption experiments were carried out to investigate the influence of pH, contact time, initial pollutant concentration, and adsorbent dosage on removal efficiency. Adsorption kinetics were analyzed using pseudo-first-order, pseudo-second-order, and Elovich models, while equilibrium data were interpreted using Langmuir, Freundlich, and Temkin isotherms.

To simulate real operating conditions of PRBs, fixed-bed column experiments were conducted under continuous flow. Breakthrough curves were obtained to evaluate the dynamic performance and service life of the reactive media. The results demonstrated that PRB systems based on natural clays and activated carbon exhibit high removal efficiency due to synergistic adsorption mechanisms and favorable surface interactions, particularly under optimized pH conditions.

The study confirms that low-cost, locally available natural materials can be successfully applied in PRB design for sustainable wastewater treatment. The proposed approach offers a practical and environmentally friendly solution for reducing pharmaceutical pollution in water bodies located in wastewater accumulation zones.