Production of 2,3-Butylene Glycol from Citrus Wastes

Early in World War II there developed an increased demand for compounds usable in the manufacture of synthetic rubber and other strategic materials. One which seemed to have great potential for such use was 2, 3-butylene glycol which possessed the added advantage that it could be produced by fermentation from noncritical surplus wheat. Cooperative efforts by universities and agencies of the United States and Canada resulted in a thorough study of all phases in developing plant-scale operations. Underkofler and Hickey (1954) have adequately reviewed these studies and no further discussion will be attempted here. Cessation of hostilities concomitant with high cost of wheat prevented subsequent commercial application. Many industrial uses for 2,3-butylene glycol have been proposed including softeners for textile sizing, solvents for dyes, components of synthetic resins, carriers for pharmaceutical products, manufacture of plastics, and automotive antifreeze (Neish, 1944; Clendenning, 1946). The postwar expansion of the Florida citrus industry has led to waste disposal problems which exceed the capacity of existing facilities. Existing processes, e.g., citrus feed molasses, designed as partial answers to this problem, produce little or no return to the processor and require costly installations. A suggested alternative is the fermentation of certain liquid citrus wastes (press liquor) to potentially higher revenue-yielding products, e.g., 2,3-butylene glycol. Press liquor, since it is a waste, is inexpensive and is readily available in sufficient quantities to meet any foreseeable demand. The present study was designed to provide basic information necessary for commercial production of 2,3butylene glycol from these wastes.