Efficiency of Waste Mussel Shells (Perna viridis) as Adsorbents for Ammonia (NH3) and Phosphate (PO43?) in Lake Water Treatment

Aquatic plants and algae can grow quickly in lake water that contains excessive levels of minerals like phosphate (PO43?) and ammonia (NH3). This overgrowth frequently jams waterways and causes algal blooms, which lower oxygen levels and kill fish. This study investigates a possible method for purifying nutrient-rich lake water, especially in lakes where ammonia levels fluctuate. The study intends to offer a cost-effective and ecologically advantageous method of treating water by assessing the usage of leftover mussel shells (Perna viridis) as a natural adsorbent. Reducing phosphate and ammonia levels in water not only helps restore ecological balance but may also boost fish populations, supporting local fisheries and the economy. This study aims to assess the efficiency of discarded mussel shells in removing phosphate (PO43?) and ammonia (NH3) from lake water. The goal is to determine which nutrient the adsorbent targets more efficiently. Experimental tests were conducted at the Machine Shop of Mapúa Malayan Colleges Laguna, while pre- and post-water treatments were performed at Cosmolab Laboratories, Inc. Lake water samples (500 mL each) were placed in three capped glass jars, each treated with a different amount of mussel shell powder: 4g, 9g, and 14g. After the adsorption process, phosphate removal efficiency was measured using the spectrophotometric method. Both 4g and 9g samples had a 71% reduction, but 14g samples had a noticeably greater reduction of 97.14%. For the 4g and 9g treatments, the phosphate concentrations decreased to 0.1 mg/L, while for the 14g treatment, they decreased to 0.01 mg/L. In contrast, ammonia levels, as determined by the phenate technique, were consistent at 0.5 mg/L in all three samples. These results imply that waste mussel shells have the potential to be used on a larger scale in water treatment systems since they are very good at eliminating phosphate from lake water.