Oxalic acid is obtained from corn cobs by subjecting the cobs to the oxidizing action of nitric acid (sp.gr.1.5) in the presence of catalysts, as V2 O5, M0, O3. The cobs, ground to 1/8” mesh, are treated either hot or cold. In the hot method, the heat is removed after decomposition of the cobs (about 5 minutes.) In the cold process, the mixture of cobs, acid, and catalyst is allowed to stand three days. An average yield of 70% is obtained by either method, but greater yields are obtained occasionally. About 5% of the yield remains in the mother liquor.
Proceedings of the Iowa Academy of Science
©1924 Iowa Academy of Science, Inc.
Webber, H. A.
"The Manufacture of Oxalic Acid from Corn Cobs,"
Proceedings of the Iowa Academy of Science, 31(1), 290-290.
Available at: https://scholarworks.uni.edu/pias/vol31/iss1/86