Biomass properties and composition vary widely. As a result, products from thermochemical conversion processes can be quite variable. The most routinely used biomass properties relevant for thermochemical conversions are heating value, proximate analysis, ultimate analysis and biochemical composition. Proximate analysis includes contents of moisture, volatiles, ash and fixed carbon. Ultimate analysis includes contents of carbon, hydrogen, oxygen, nitrogen, and sulfur. These contents can be reported on a dry basis (d. b.), wet basis (w. b.) or dry and ash-free basis (d. a.f.). The difference among these bases is the mass that the content (such as carbon content) is compared with. Content given in dry basis implies that the content is compared with moisture-free biomass. Content given in wet basis implies that the content is compared with biomass containing moisture. Content given in dry and ash-free basis implies that the content is compared with moisture and ash-free biomass material. Properties of several biomass are presented in Tables 1 (proximate analysis), 2 (ultimate analysis) and 3 (biochemical compositions). However, the above properties do not

completely characterize any biomass feedstock because biomass feedstocks with similar properties and composition stated above may differ in their polymer structure resulting in different products through thermochemical conversion processes.

To understand and reliably predict the effects of the biomass composition and properties on thermochemical conversion processes and products, several equipment have been used by researchers. The most common equipment includes thermogravimetric analyzer (TGA), dynamic thermogravimetric analyzer (DTA), pyrolyzer (Py), Fourier-transformed infrared spectrophotometer (FTIR), gas chromatography (GC) and mass spectrometer (MS) (Lapuerta et al. 2004; Dejong et al. 2007; Fahmi et al. 2007; Boateng et al. 2010; Pasangulapati et al. 2012; Ribechini et al. 2012). TGA provides weight loss of biomass as temperature is varied. Different weight loss stages in gasification and pyrolysis modes can be observed in the TGA data. The stages are separated more clearly using the derivative of the weight loss with time or temperature. Heating rates available in pyrolyzer is much higher than those in TGA, hence pyrolyzer is widely used to obtain volatiles simulating pyrolysis condition. The volatiles evolved from the biomass thermal degradation is detected by FTIR and MS.