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Torrefaction is known to reduce the logistical costs of biomass. Torrefied biomass’ prospects as feedstock for fermentation to liquid biofuel are largely unknown. This study investigated the interactions of torrefaction and alkaline pretreatment of wheat straw on glucose yields from enzymatic hydrolysis, including treatment order and the potential for pH to play a role in the process. Across a range of torrefaction severities with temperatures of 200 °C, 220 °C, and 240 °C and durations of 20, 40, and 60 min, torrefaction had a negative impact on glucose yield of wheat straw with or without alkaline pretreatment and regardless of the order of alkaline pretreatment. Alkaline pretreatment after torrefaction results in higher glucose yield than alkaline pretreatment before torrefaction, or by torrefaction alone. Hence, there is the prospect for adding logistical benefits of torrefaction to the bioethanol system if alkaline pretreatment is coupled with torrefaction. Decreasing trend in pH with increase in torrefaction severities was observed for trials without buffer, indicating chemical changes causing the decrease in pH might be associated with the reduction in yield.

The concept of Frank's hypothesis (that is the effect of large tetra alkyl ammonium iodides on the solvent structure, especially in the ion -ion and ion -solvent interactions) was found to be not applicable when water was replaced by one of organic solvent. That is, if study involves ion-ion and ion -solvent interactions in 1, 3 -Butane diol -DMF solvent mixture. The densities of these mixture and some adding tetra alkyl ammonium iodide salts solutions at different concentrations (0.02 -0.14 M) have been determined at 298.15 K using Magnetic Float Densitometer technique. The apparent molar volume (ϕ v ) and apparent molar volumes of transfer ∆ϕ v 0 (tr) of the electrolytes in above solvent mixtures were calculated. ϕ v vs √C curves are plotted and explained the nature of molecular interactions by using slope (S v ) values. Also, the significant role of varying dielectric constants (ϵ) of the selected solvent mixtures in the ionic interaction is discussed.