Biomass represents an abundant carbon-neutral renewable resource for the production of bioenergy and biomaterials, and its enhanced use would address several societal needs. Advances in genetics, biotechnology, process chemistry, and engineering are leading to a new manufacturing concept for converting renewable biomass to valuable fuels and products, generally referred to as the biorefinery. The integration of agroenergy crops and biorefinery manufacturing technologies offers the potential for the development of sustainable biopower and biomaterials that will lead to a new manufacturing paradigm.

Ion Interaction parameters for 304 single salts In aqueous solution have been obtained lor PHzer's equations. For most of the cases we evaluated, the range of molality extended up to saturation when data were available. The calculated activity coefficients of HCI, LIBr, CaBr2, Pr(N03)3, and MgS04 from our results and Pltzer's were compared to available smoothed experimental data. The comparisons show better agreement with experimental data when we use values of our parameters which were evaluated at higher concentrations than those used by Pitzer.

We have mapped the formation of tars during white oak thermochemical conversion using a bench scale laminar entrained flow reactor (LEFR). White oak particles (80 mesh, <180 μm) were pyrolyzed under conditions not limited by heat transfer. Measurements were made with residence times of 0.2, 0.4, 0.6, and 0.8 s, between 500 and 900 at 100 °C increments, and with residence times of 1 s at temperature from 450 to 950 °C at 25 °C increments. Products were monitored with a molecular beam mass spectrometer (MBMS), and the mass spectra were analyzed using model-free multivariate analysis (multivariate curve resolution). Six groups of correlated masses were identified that suggest the mechanisms of pyrolysis and gasification. The first group of masses (lowest temperature) is associated with primary species from lignin and hemicellulose, followed by cellulose products. The next two groups (increasing temperature) are composed of secondary products resulting from the cracking of carbohydrate vapors and the cracking of lignin in the gas or solid phase. Molecular weight growth products are seen in the next two groups including substituted aromatic compounds in the fifth group and polycyclic aromatic hydrocarbons (PAHs) in the sixth group. The results of this study show that as the temperature of pyrolysis is increased, the molecular weight of the tars decreases up to 750 °C, because the pyrolysis vapors are cracked. As the temperature increases beyond 750 °C, molecular weight growth is seen with increasing temperature. The analysis also shows that as the temperature increases from 450 to 950 °C, oxygen is lost from the tars and converted into CO and CO2. The char samples were collected and analyzed with light and electron microscopy. This analysis revealed that micropores develop in the cell wall around 550 °C and increase in size and coalesce into a cenosphere morphology with increasing temperature. Above 850 °C, these cenospheres appear to rupture, releasing their contents into the gas phase. This rupture event correlates with increased MBMS signals from PAH-associated masses.

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