Water pollution is a global issue that affects both human health and the environment. The increasing use of the methylene blue (Mb) dye in various industrial applications poses significant risks. The study aimed to use hydrochloric acid-modified Ziziphus Spina Christi powdered leaves (ZSC) as an effective and low-cost adsorbent for removing Mb dye from effluents. Batch experiments were conducted with contact times of 10–180 minutes, initial dye concentrations of 10–60 mg/L, temperatures of 25–60°C, pH values of 5–9, and sorbent dosages of 0.25-2 g per 40 ml of dye solution. The results showed that the highest removal efficiency of Mb dye was 97.51% using an initial concentration of 10 mg/L, 1.5 g of adsorbent, pH 8, at 50 °C, a contact time of 60 minutes, a particle size of 0.075 μ m, and a stirring speed of 150 rpm. The ZSC was characterized using SEM and FTIR techniques, and the adsorption kinetics were found to follow the pseudo-first-order model, with a correlation coefficient of 0.969. In general, the modified ZSC is an auspicious, friendly, and cost-effective adsorbent for removing Mb dye from aqueous solutions.
Obaid et al. (2026) studied this question.