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Highlights Tree fruit oils of Allanblackia spp., shea butter and palm kernel were evaluated for their physical and chemical properties using DSC, TGA and FTIR. All oils were thermally cycled to investigate their stability and reliability for potential use as phase change materials (PCMs) for thermal energy storage. Allanblackia spp. oil demonstrated greatest potential for use as PCM in thermal energy storage systems.

This study compared the yield of biodiesel produced from tall oil fatty acids (TOFA) via (i) homogeneous catalyst (sulfuric acid) and (ii) a heterogeneous catalyst (Amberlyst® BD20, together with Ambersep BD 19 (Midcontinental Chemical Co., Olathe, KS, USA)® using a batch reactor. The effect of operation conditions including temperature, catalyst concentration, methanol: oil ratio and reaction time on esterification yield were investigated. Gas chromatographic data showed that the major fatty acids present in the TOFA are oleic acid (C18:1n9) and linoleic acid (C18:2n6). Homogenous catalysis yielded 96.76% biodiesel compared to 90.24% for heterogeneous catalysis. Optimized conditions for homogenous catalysis were at a catalyst concentration of 0.5 w/w%, 15:1 methanol: oil mass ratio at 55 °C for 60 min. FTIR results also showed that the homogeneous catalyst yielded a more complete reaction toward biodiesel production in a shorter time (60 min) compared to the heterogeneous catalyst (4.7 h). For heterogeneous catalysis, the highest yield and the lowest acid value were achieved after a second recycling because the reactants were not fully in contact with the catalyst during the first recycling. The catalyst did not show a reduction in catalytic activity even after the fourth recycling. However, the acid value was higher than that for ASTM standards for biodiesel.

Commercial lignin is a by-product of pulping and the emerging bio-refinery industries. Herein, we report the hydrothermal treatment (HTT) or conversion (HTC) of three commercial types of lignin to carbonaceous materials. HTC of lignin was carried out in an autoclave in the presence of water at temperature and pressure of approximately 300°C and 1000 psi respectively. Morphological, physical and chemical properties of parent lignin and their hydrothermally derived carbonaceous materials were characterized by X-ray diffraction, scanning electron microscopy (SEM), thermogravimetric analysis, elemental composition, Fourier-transform infrared and Raman spectroscopies (FTIR). This study demonstrated differences in the morphology of carbons from the three lignin types. SEM analysis showed that hydrothermally derived carbonaceous materials from Mascoma lignin contained spherical particles with diameters ranging from 50 to 250 nm whereas that from ammonium and sodium lignosulfonate lignins contained similar particles but were highly agglomerated. The better characteristics of the post-HTT Mascoma carbon vis-à-vis post-HTT ammonium and sodium carbons are also evident in the results obtained from X-ray diffraction, thermo-gravimetric analysis, and FTIR spectroscopy. Thus, carbonaceous materials can be obtained from low-value commercial lignins via HTT and their properties are influenced by the type of lignin.