3.1 Phase transition
MDSCTM allows for separation and evaluation of thermodynamic and kinetic processes within the regions of glass and melting transitions as shown in equation (1). Endothermic or exothermic enthalpy relaxation may occur within the glass transition range owing to changes in the temperature of the sample. There was no glass transition (Tg ) on total heat flow and non-reversible heat flow profiles except on reversible heat flow profiles for all biomass samples tested. There was glass transition (Tg ) at a temperature of 239 K and the enthalpy change of 12.586 J/g with an endothermic peak temperature of 292.333 K for BA sample, and aTg of 211 K, an enthalpy change of 22.096 J/g at an endothermic peak temperature of 287 K for BCN samples on the reversible heat flow profiles which was an indication of a structural transformation of the samples studied, i.e. BA and BCN samples; that is reversible with any temperature changes [29, 30]. The lowerTg for BCN samples is an indication of a rapid breakdown of aromatic constituents in Beta vulgaris supplemented biomass owning to the residual free cyanide within the synthetic wastewater used, thereby enhancing microbial growth during the free cyanide biodegradation process. In addition, melting transition (Tm ) was observed on the reversing heat flow profiles for all samples studied – see Table 1.
Table 1: Effect of melting temperature on the samples