Cadmium is a toxic metal that can contaminate water sources and pose serious health risks to humans and the environment. Therefore, there is a need for developing low-cost and eco-friendly methods for cadmium removal from water. In this research, we investigated the efficacy of barley straw in removing cadmium ions from aqueous solutions. The adsorbent utilized was laboratory-scaled barley straw that underwent pulverization via standard ASTM sieves, specifically those within the 40 to 120-mesh sieve size range. The functionalization of barley straw was achieved via treatment with a 0.8 M NaOH solution. The adsorbent was subsequently characterized by FTIR analysis to identify the presence of functional groups. The FTIR analysis indicated that the modification of barley straw led to an elevation in the stretch vibration band of hydroxyl and carboxyl groups. At the optimized experimental condition, a cadmium removal efficiency of up to 98.60% was achieved. These results demonstrate the potential of barley straw as an effective adsorbent for removing cadmium ions from aqueous solutions. تفاصيل المقالة