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This study investigated biodiesel production from jatropha seeds in a single step, i.e. by simultaneous solvent extraction and transesterification of jatropha oil, and possibility to transform the obtained cakes into binderless particleboards. n -Hexane was used as extracting solvent. The best operating conditions were identified to obtain optimal biodiesel yield and quality, and optimal physical and mechanical properties for binderless particleboards. Biodiesel yield was usually influenced by operating conditions, and the influences of both n -hexane to seed and methanol to oil ratios were most significant. An increase in n -hexane to seed ratio (from 1:1 to 3:1) combined with the decrease in methanol to oil ratio (from 13.3:1 to 8.0:1) led to an improvement in biodiesel yield. The best biodiesel yield (92% with a fatty acid methyl ester purity >98%) was obtained from 2:1 n -hexane to seed ratio, 10.6:1 methanol to oil ratio, 200–600 rpm stirring speed, 50 °C temperature and 6 h reaction time. Operating conditions had no significant effect on the biodiesel quality, except the n -hexane to seed ratio. Moreover, cohesive particleboards were produced from the obtained cakes, proteins and fibers acting respectively as binder and reinforcing fillers. An increase in the cake moisture content significantly improved the particleboard properties. The most promising binderless particleboard was manufactured from cake B under 20% cake moisture content and 160 °C pressing temperature. Its properties were 0.87 g/cm 3 density, 8.4% moisture content, 7.2 MPa modulus of rupture, 10.4 GPa modulus of elasticity, 0.14 MPa internal bonding strength, 52% water absorption and 20% thickness swelling after 24 h immersion in water. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study was to investigate solvent extraction and in situ transesterification in a single step to allow direct production of biodiesel from jatropha seeds. Experiments were conducted using milled jatropha seeds, and n-hexane as extracting solvent. The influence of methanol to seed ratio (2:1–6:1), amount of alkali (KOH) catalyst (0.05–0.1mol/L in methanol), stirring speed (700–900rpm), temperature (40–60°C) and reaction time (3–5h) was examined to define optimum biodiesel yield and biodiesel quality after water washing and drying. When stirring speed, temperature and reaction time were fixed at 700rpm, 60°C and 4h respectively, highest biodiesel yield (80% with a fatty acid methyl ester purity of 99.9%) and optimum biodiesel quality were obtained with a methanol to seed ratio of 6:1 and 0.075mol/L KOH in methanol. Subsequently, the influence of stirring speed, temperature and reaction time on biodiesel yield and biodiesel quality was studied, by applying the randomized factorial experimental design with ANOVA (F-test at p =0.05), and using the optimum values previously found for methanol to seed ratio and KOH catalyst level. Most experimental runs conducted at 50°C resulted to high biodiesel yields, while stirring speed and reaction time did not give significantly effect. The highest biodiesel yield (87% with a fatty acid methyl ester purity of 99.7%) was obtained with a methanol to seed ratio of 6:1, KOH catalyst of 0.075mol/L in methanol, a stirring speed of 800rpm, a temperature of 50°C, and a reaction time of 5h. The effects of stirring speed, temperature and reaction time on biodiesel quality were not significant. Most of the biodiesel quality obtained in this study conformed to the Indonesian Biodiesel Standard. [Copyright &y& Elsevier]