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This study investigated the physical properties of water-blown rigid polyurethane (PU) foams made from VORANOLV R 490 (petroleum-based polyether polyol) mixed with 0-50% high viscosity (13,000-31,000 cP at 22 C) soy-polyols. The density of these foams decreased as the soy-polyol percentage increased. The compressive strength decreased, decreased and then increased, or remained unchanged and then increased with increasing soy-polyol percentage depending on the viscosity of the soy-polyol. Foams made from high viscosity (21,000-31,000 cP) soy-polyols exhibited similar or superior density-compressive strength properties to the control foam made from 100% VORNAOLV R 490. The thermal conductivity of foams containing soy-polyols was slightly higher than the control foam. The maximal foaming temperatures of foams slightly decreased with increasing soy-polyol percentage. Micrographs of foams showed that they had many cells in the shape of sphere or polyhedra. With increasing soy-polyol percentage, the cell size decreased, and the cell number increased. Based on the analysis of isocyanate content and compressive strength of foams, it was concluded that rigid PU foams could be made by replacing 50% petroleum-based polyol with a high viscosity soy-polyol resulting in a 30% reduction in the isocyanate content.

During the conversion of glycerol to propylene glycol, highly selective conversion is necessary for commercial viability. The greatest strides in achieving high selectivity are attained with catalyst and temperature. For the conversion of glycerol to propylene glycol, these parameters can be optimized to achieve selectivities of greater than 80%. This paper is on the optimization of more-subtle parameters such as concentration, water content, pressure, isothermal operation, and residence time to achieve selectivities in excess of 90%. Data reveal that low concentrations are important to reduce by-product whose formation relies on second-order reaction mechanisms. Water is important to reduce dehydration reactions and indirectly helps to maintain more-isothermal operation. An optimal hydrogen partial pressure between 5 and 15 bar minimizes the cumulative amount of by-product that results from hydrocracking versus dehydration side-reactions.

This article describes the investigations carried out on the vapor-phase hydrogenolysis of glycerol to acetol over a copper-chromite catalyst in a packed bed flow reactor. The effects of reaction method (liquid-phase vs. vapor-phase mode), vapor-phase reaction with gas feed, reaction temperature, catalyst loading, and hydrogen feed rate were studied to arrive at optimum conditions. Operating the reactor in vapor-phase mode dramatically reduced the amount of undesired by-product formation, and thereby increased the overall yield of acetol and propylene glycol. The optimum reaction temperature is near 2208C. Higher hydrogen feed rates increased propylene glycol selectivity. The proposed production scheme has application for production of both acetol and propylene glycol from the crude glycerol that contains various soluble salts.

The effect of incorporating 1–7% microsphere and nanoclay fillers on the physical properties of polyurethane (PU) foams containing 15% soybean oil-based polyol was investigated. Increasing filler percentage reduced the PU foam density. The compressive strength of PU foams decreased slightly when increasing the microsphere content from 1 to 3% and then increased. At 7% microsphere content, the foams displayed the same compressive strength as the control foams made from 100% petroleum polyol. For PU foams reinforced with nanoclay, their compressive strength changed little from 1 to 5%, but decreased at 7% due to a lower density and weaker matrix structure. Foams containing 5 to 7% microspheres or 3 to 7% nanoclay had density-compressive strength comparable or superior to the control. Foams reinforced with fillers had more cells and smaller cell size than foams made from 15% soy-polyol but without fillers. During the foaming process, the maximal temperatures reached by PU foams were not affected by the presence of 1 to 7% of microspheres or nanoclay, but slightly lower than the control. In addition, foams with fillers displayed roughly the same thermal conductivity as soy-polyol based foams without fillers.