Influence of pH on Nitrate Removal from Groundwater Using Shredded Tire Rubber

Abstract:

The findings from this study proved the possible usefulness of shredded recycled rubbers from scrap tires as a cheap and effective method for eliminating nitrate ions from water, especially within a certain pH range. Maximum adsorption efficiency was found to occur around pH = 6 which suggested that the surface charge on the adsorbent and the concentration of ions in the medium observed were critical for adsorption. Under controlled conditions and a pH of 6 with an original concentration of 100 mg/L, the adsorption efficiencies of NaNO₃ and KNO₃ were 67% and 60% respectively. These increased to 77% and 70% at 200 mg/L, pH 6. These results elucidate that the type of cation and the chemistry of the solution influences the adsorption process. The kind of nitrate salt employed also had an impact on removal efficiency, with potassium nitrate performing better than sodium nitrate, highlighting the relevance of the associated cation type in the process. As a result, the utilization of recycled rubber might be regarded as an environmentally viable solution for treating nitrate-contaminated water, especially in decentralized treatment systems and mild pH conditions. In addition, shredded tire rubber provides an effective, low-cost, and sustainable solution for nitrate-contaminated groundwater treatment.

• Periodical: Key Engineering Materials (Volume 1052)
• Pages: 145-150
• DOI: https://doi.org/10.4028/p-Idtg0g
• Online since: May 2026
• Authors: Aya M. Khalid, Haneen A. Kh. Karaghool*
• Keywords: Environmental Sustainability, Groundwater, Nitrate, Shredded Tire Rubber

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