Lignin Ammoxidation: Synthesis of Nitrogen Releasing Soil Conditioning Products from Waste Pulp Liquor and Their Pot Trial Evaluation

Lignin is a precursor of humus, and by-product the pulp paper industry. This study investigated synthesis soil conditioning materials from industrial lignins (kraft, soda sulphite), through ammoxidation. The were characterized ammoxidized in 1 L Parr reactor at 80 °C, 10 barg, for 4 h, with 7 wt% ammonia lignin reaction mixture. A plant trial assessment products was conducted over four weeks. N-lignins C/N ratios 12.30, 15.81, 14.64 obtained kraft, sodium lignosulfonate against standard requirement < 20. However, an oxidation step 5% hydrogen peroxide required (prior to ammoxidation) because criterion (C/N 20) could not be met under conditions. In trial, N-modified kraft (3.50 t/ha) (3.21 recorded crop yields that 71% 57% higher than control (2.04 t/ha), respectively. lignosphonate, while it requirements use as fertilizing material terms nitrogen content, resulted complete failure. Further characterization showed had high pH (8.81 pH) salt index (63.62%) due pulping technique used its isolation. Kraft successfully synthesize are suitable materials.