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Research was performed to determine whether it was technically feasible to use boronic acid extractants to purify and concentrate the sugars present in hemicellulose hydrolysates. Initially, five types of boronic acids (phenylboronic acid, 3,5-dimethylphenylboronic acid, 4-tert-butylphenylboronic acid, trans-β-styreneboronic acid or naphthalene-2-boronic acid) dissolved in an organic diluent (Shellsol  2046 or Exxal  10) containing the quaternary amine Aliquat  336 were tested for their ability to extract sugars (fructose, glucose, sucrose and xylose) from a buffered, immiscible aqueous solution. Naphthalene-2-boronic acid was found to give the greatest extraction of xylose regardless of which diluent was used. Trials were then conducted to extract xylose and glucose from solutions derived from the dilute acid hydrolysis of sugar cane bagasse and to then strip the loaded organic solutions using an aqueous solution containing hydrochloric acid. This produced a strip solution in which the xylose concentration had been increased over 7× that of the original hydrolysate while reducing the concentration of the undesirable acid-soluble lignin by over 90%. Hence, this process can be exploited to produce high concentration xylose solutions suitable for direct fermentation.

The use of mathematical models to predict the thermal resistance of polymer-based, intumescent coatings are reviewed and their limitations are discussed. A mathematical model is derived to describe the developing temperature profile across an intumescent coating when exposed to a radiant heat source. The model includes the effects of: the endothermic and exothermic reactions; convective heat transfer as degradation gases are transported through the coating; radiation heat transfer across the developing porous solid; and the increase in thermal resistance as gases are formed and the coating expands. The model predictions are compared with experimental data from the heating of epoxy-based and vinyl acetate-based intumescent coatings in a cone calorimeter. A sensitivity analysis is performed to show the effect of the thermal characteristics of the coating on the thermal resistance of the material. The application of the model to newly developed intumescent coatings is discussed.