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Jatropha is a species of high economic value, their roots, stems, leaves, fruit can be used. Seed oil content can be as high as 60%, oleic acid and linoleic acid content of more than 70%, the high content of unsaturated fatty acids, low iodine value, is a semi-drying oil, good fluidity, is an ideal raw material for biodiesel production, Jatropha seed oil biodiesel prepared to meet Euro II emission standard. Jatropha seeds rich in protein content, accounting for 27% to 32% of the weight of the seeds, amino acid composition is also more balanced, but due to the presence of Jatropha seeds of toxic proteins (Curcin) and phorbol ester, Jatropha seeds after oil extraction The cake can not be directly forage mainly used as a fertilizer. The use of appropriate protein extraction process, to explore the removal of Jatropha seed protein toxins, will be conducive to the development and utilization of Jatropha seed cake. Jatropha seed oil and Jatropha seeds protein on the following aspects: (1) the subject first cold pressed - leaching Preparation of Jatropha seed oil test that the press pressure 40MPa, press time 120 min, temperature 65 ° C, cold-pressed test under the conditions of the raw material moisture content of 10%, better oil, the oil yield of approximately 41%, 28% cold-pressed cake residual oil amount. The use of hexane as a solvent in a solvent ratio of 1.2:1, the temperature of 55 ° C, time 30min, a continuous leaching of five times under the conditions of the cold pressed cake, the final Jatropha seed meal residual oil amount as low as 0.8%. After degumming, vacuum dehydration Jatropha seed oil acid value 15.49mgKOH / g oil, homogeneous base-catalyzed preparation of biodiesel raw materials are required acid value ≤ 1.0 mgKOH / g oil, hence the need for deacidification treatment. In this paper, the solvent extraction deacidification and concentrated sulfuric acid catalyzed pre-esterification the deacidification two methods were studied. By single factor experiment and response surface analysis, the optimal process of Jatropha seed oil solvent removal by acid: methanol to oil ratio (V / V oil) 2.0:1, the Jatropha seed moisture content of 0.08%, extraction temperature 45 ° C , serials and extracted five times, each extraction 10min. Pre-concentrated sulfuric acid catalyzed esterification deacidification by adding a co-solvent tetrahydrofuran, after a single factor and orthogonal experiments analysis, the optimal process: methanol added amount (V / V oil) 0.85:1, reaction time 45min, the reaction temperature 65 ° C, the amount of catalyst (V / V oil) 0.012:1, added amount of co-solvent (V / V oil) 0.5:1. 3 to select the appropriate co-solvent to promote the formation of methanol and Jatropha oil are phase system. By contrast the nature of the solvent, as well as in different temperature conditions, diethyl ether or tetrahydrofuran solvent and Jatropha seed oil, methanol formed in the ternary phase diagram of the comparator, and the final choice of tetrahydrofuran as a cosolvent present study. In concentrated sulfuric acid catalyzed pre-esterification deacidification conditions using tetrahydrofuran as a co-solvent, NaOH as catalyst, Jatropha seed oil methyl ester biodiesel production by single factor and orthogonal Experimental design that the added amount of methanol (V / V oil) 0.56:1, reaction time 18min, the reaction temperature is 65 ° C, the catalyst addition amount of 1% (w / w oil), the added amount of cosolvent (V / V oil) 0.5 : 1 under the conditions, a higher rate of conversion of methyl. 5 In this paper, the alkali extraction and acid precipitation Jatropha seeds Jatropha seed meal protein extraction studies. Experimental study on the impact of various factors on the extraction rate by single factor and orthogonal test to optimize the process conditions. The optimum conditions: alkali extraction and solid-liquid ratio 1:11, pH 8.5, temperature 55 ° C, time 100min; acid precipitation pH 4.4, temperature 55 ° C, time 40min. Under the process conditions, Jatropha seed protein extraction rate reached 76.63%, 81.18% purity of the protein isolates.
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