Ultrastructure of rice straw subjected to ammonia reactor processing

• Zoraida Medina de Salcedo Universidad del Zulia-Venezuela
• Betzabé Sulbarán de Ferrer Universidad del Zulia-Venezuela
• Alexis Ferrer Universidad del Zulia-Venezuela
• Graciela Ojeda de Rodríguez Universidad del Zulia-Venezuela

Resumo

In this study a method that uses pressurization and depressurization with ammonia processing (PDA) was applied to rice straw samples. The effect of PDA on the structure of rice straw samples with various moisture contents (15%, 35% and 60%); different treatment times with ammonia (0 min, 6 min and 20 min) and four combinations of addition and treatment times of ammonia (1-0 min, 1-5 min, 4-0 min, 4-5 min) was determined. Morphological changes were detected by Scanning Electron Microscope. PDA treatment produced noticeable structural changes in rice straw. As moisture content Increased there were more cellular architectural losses of parenchyma tissue. As ammonia treatment time increased, more shredding of cellulose fibrils appeared and the higher the ammonia addition time and the treatment time combination, the higher the parenchymal and epidermal cells collapse as well as that of the epidermal wax.