An investigation was carried out to develop an economical process for making nitrogenous fertilizers from ammonia and cellulosic waste materials such as corncobs, cornstalks, and oat hulls. In this endeavor, two different methods were investigated;One method was based on hydrolysis of the hemicelluloses in these materials with dilute solutions of mineral acids or salts followed by ammoniation with anhydrous ammonia of the hydrolysate. With corncobs, when 8.25 percent sulfuric acid and a liquid/solid ratio of 2.0 was used for hydrolysis, and ammoniation was carried out slightly above room temperature, a product was obtained containing 7.4 percent total nitrogen of which 4.2 percent was organic nitrogen (Product A), With the same hydrolysis conditions and an ammoniation temperature of 249°C, a product was obtained containing 9.5 percent nitrogen of which 56 percent was organic nitrogen (Product B). In Product A, 86.4 percent of the total nitrogen was water-soluble, and in Product B only 17.6 percent was water-soluble. Normal and concentrated superphosphates or dilute phosphoric acid in the hydrolysis step did not result in as much organic nitrogen an sulfuric acid;The second method involved the ammoniation of the cellulosic materials with anhydrous ammonia. By this process, a product containing 4.6 percent total nitrogen was obtained with corncobs at a temperature or 300°C (Product C). In this product, all the nitrogen was organic and none of it was water-soluble;Small-scale engineering equipment for producing Product A was built and tested. Products were made which were essentially the same as those prepared on a laboratory scale;An evaluation of Products A, B, and C as fertilizer materials was made. Tests were made to determine chemical stability, hygroscopicity and caking characteristics. These tests showed that Products A, B, and C could be used in mixed fertilizers. Greenhouse plant-growth tests were carried out. Product A proved to be better than Milorganite, a commercial nitrogen fertilizer made from sewage, and was almost an good as ammonium sulfate, Products B and C did not compare well with Product A ammonium sulfate, or Milorganite in the plant-growth tests; however, under different conditions of a longer growing season, these two products might be better;A preliminary cost analysis indicated that Product A might compete with ammonium sulfate and could easily undersell Milorganite;It is recommended that further pilot plant work be carried out on the production of Product A.
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