Ojiako E. N. and Mokwe C. A.
comparative analysis of oxalic acid produced from rice husk and cocoa seed was carried out by nitric acid oxidation of carbohydrates in order to ascertain which waste sample produced a better yield. The results obtained showed that HNO3:H2SO4 acid ratio of 50:50 for rice husk sample gave a percentage yield of 48.0, 63.2, and 49.3 at temperatures of 55°C, 75°C, and 85°C respectively. At 60:40 acid ratio, the percentage yields were 47.8, 67.8 and 46.6 at the three different temperatures respectively. At 80:20 acid ratio, the percentage yields were 50.2, 67.0 and 45.4 at the three different temperatures .For cocoa seed, a percentage at 50:50 acid ratio, were 44.6, 54.7 and 47.4 at temperatures of 55°C, 75°c and 85°C respectively. At 60:40 acid ratio, the percentage yields were 45, 54.8 and 46.4 at these three different temperatures. At 80:20 acid ratio, the percentage yields were 47.6 51.3 and 45.8 at the above stated temperatures. The variable ratio of 60: 40 gave the maximum yield at the maximum temperature of 75°C for the both samples. But in comparison, it was found that the oxalic acid produced from rice husk gave higher yield by 13% than that from cocoa seed. The use of these raw materials to produce oxalic acid will minimize environmental pollution.
