For the preparation of Fertilizer B, 50 g of the homogenized plant residue was placed in a beaker containing 20 mL of 20% sodium hydroxide. The mixture was heated at 100-110°C for 10 minutes, after which 15 mL of 30% sulphuric acid was added on continual heating for 10 minutes. Following cooling to room temperature, and the mixture was oven-dried at 47°C for 1 hour, as shown in Figure .