Corn Waste Utilization: Furfural, Hydrol, and Products from Cobs and Husks
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The waste products obtained from corn processing reach far beyond corn extract and monosodium glutamate. When the corn plant is fully and comprehensively processed, scientists have calculated that more than two hundred distinct products can be derived from it.
Separating glucose crystals from the mother liquor yields hydrol, a byproduct used in leather manufacturing, in the production of artificial fibre, and in the medical industry. 
What are corn cob husks and cores used for?
The husks and the cores of corn cobs also find valuable uses. Through chemical processing they yield alcohol or furfural, a chemical product with antiseptic properties that is used in the manufacture of varnishes and paints.
Furfural production begins by crushing the cobs and treating them in a two-percent solution of sulphuric acid. Steam is fed into the apparatus and carries off the furfural that forms; once cooled, the furfural condenses and is bottled. The steps in outline are:
- Crush the corn cob cores.
- Treat the crushed material in a 2% sulphuric acid solution.
- Introduce steam, which carries away the furfural as it forms.
- Cool the vapour so the furfural condenses, then bottle it.
This process rests on the chemical conversion of pentosans, substances close in composition to starch. Under deep hydrolysis, pentosans produce a particular sugar — xylose — from which further chemical processing can yield trioxyglutaric acid, a valuable substitute for citric acid.
The dry distillation of corn cob cores opens up another set of chemical products. From the cores it is possible to obtain acetic acid, formic acid, methyl alcohol, and other compounds.
What can corn stalks and leaves be turned into?
Corn stalks and leaves contain cellulose, and on that basis these seemingly useless parts of the plant can be made into paper, artificial silk, and other goods. 
By way of conclusion, one figure underscores the scale of it all: researchers estimate that the complete and comprehensive processing of the corn plant can yield more than two hundred different products.
