| China is a country short in supplies of petroleum and natural gases. The percentage of imported petrols and edible vegetable oil in China has gone up to60%in recent years. Along with the rapid development of national economy and fast depletion in fossil energy resources, however, the conflict between the supply and demand in biofuel and edible vegetable oil has become one of the key issues. As an alternative solution to energy shortage crisis, use of biofuel as a green energy resource has been received worldwide attention.To fulfill the further need in biofuel production it is thus of high importance to promote the cultivation of oil-rich plants and to develope new green technologies for biofuel processing with high efficiency. Swida wilsoniana is one of the typical plant species for biodiesel feedstock. The oil content in the whole fruit of Swida wilsoniana is higher than30%. Its oil can be converted into products in light industry and biodiesel production. Based on the principle of ecological energy value, the present study is focused on the establishment of a new green bio-energy transform technology system using the fruit of Swida wilsoniana as raw material. The results obtained from the present work will be useful with respect to the enhancement of oil-plant cultivation, reduction of fossil energy consumption, ensurence of national energy-safty and promotion of low carbon Economy.Along with the rapid development of national economy and fast depletion in fossil energy resources, however, the conflict between the supply and demand in biofuel and edible vegetable oil has become one of the key issues. The consumption of the edible vegetable oil in China has been increasing significantly and the proportion of the edible vegetable oil imported from overseas has amounted up to more than60%. China is a country short in supplies of petroleum and natural gases and the percentage of imported petrols in China has gone up to60%in recent years. As an alternative solution to energy shortage crisis, use of biofuel as a green energy resource has been received worldwide attention. To fulfill the further need in biofuel production it is thus of high importance to promote the cultivation of oil-rich plants and to develope new green technologies for biofuel processing with high efficiency. Swida wilsoniana is one of the typical plant species for biodiesel feedstock. The oil content in the whole fruit of Swida wilsoniana is higher than30%. Its oil can be converted into products in light industry and biodiesel production. Based on the principle of ecological energy value, the present study is focused on the establishment of a new green bio-energy transform technology system using the fruit of Swida wilsoniana as raw material. The results obtained from the present work will be useful with respect to the enhancement of oil-plant cultivation, reduction of fossil energy consumption, ensurence of national energy-safty and promotion of low carbon Economy.In this work, the Swida wilsoniana fruits of the improved varieties (Xianglin Gl) cultivated by the Hunan Academy of Forestry (HAF) were selected as the raw material, to explore the bio-transformation of the Swida wilsoniana fruit on the basis of bio-techniques, green chemical engineering technology and emergy theory. Grounded on the comprehensive analysis of the composition of Swida fruits, the thesis probed into the green technologies of efficient oil extraction and clean liquid fuel bioconversion. In addition, life cycle assessment of the whole procedure was carried out. A set of green conversion technology system on Swida wilsoniana fruit was build up, which provided a theoretical ground and technology support for energy-application of Swida wilsoniana fruit. The results were summerized as follows:1. The compounds and distribution of fatty acids in Swida wilsoniana fruit (Xianglin G1) were systematically investigated, and the near infrared NIR model and database of Swida wilsoniana fruit were built.①The whole fruit was included sarcocarp (41.32%), testa (49.93%) and kernel (8.75%). The oil content varied in the different part of fruit, which was shown as55.00%,11.53%and62.14%in sarcocarp, pit and kernel, respectively. Oleic acid and linoleic acid were the main fatty acids in fruit. The main fatty acid compounds in sarcocarp were cetylic acid (24.41%), linoleic acid (32.46%), oleic acid (30.07%) and octadecanoic acid (1.64%), respectively. The main fatty acid compounds in testa were cetylic acid (12.48%), linoleic acid (54.79%), oleic acid (26.93%) and octadecanoic acid (2.18%), respectively. The main fatty acid compounds in testa were cetylic acid (6.61%), linoleic acid (58.80%), oleic acid (22.32%) and octadecanoic acid (2.03%), respectively.②The Swida wilsoniana fruit (Xianglin G1) was composed of oil of33.95%, cellulose of29.16%, protein of7.72%, starch of10.60%, sugar of3.22%, water of9.36%, phospholipid of0.66%, and some other of5.33%.③Based on46samples of fruit, the Near Infrared Spectroscopy (NIRS) model was established with the convention properties of fruit including oil content, moisture and calorific value. The correlation coefficients of oil content, moisture, protein and calorific value were0.99,0.95,0.91and0.96, respectively.2. The new "cold pression-n-butyl alcohol extraction" procedure was built up in the present work.①That procedure can be carried out without preheating, which simplifying process with lower energy requirement. In addition, protein inside would be applied as an industrially feedstock. The residual oil content of once-pressing was lower than7%, when the operation condition was fruit moisture9%, pressing axle rotation speed30-40rpm, and exit diameter4-8mm.②The by-products can be extracted by n-butyl alcohol with higher efficiency during cold compressing. The optimal condition was shown as:extraction3times, extraction time90min, extraction temperature60℃and liquid/solid ratio1.2:1, in which the oil extraction rate achieved around88.62%.③The compound enzyme of "cellulose enzyme+neutral protease" was adopted to realize oil extraction from Swida wilsoniana fruit in this study. The optimal operation process was described as following:adding2.5%of protease into system after the treatment of cellulose enzyme3h with the mixing ratio of enzyme of4:1and enzymolysis time of4h. The color of extracted oil was lighter. That process is better than the other processes with less impurity and better fluidity. However, the oil extraction rate reached80.54%.④The energy consumptions of cold-pressing were decreased by "cold pression-rc-butyl alcohol extraction" with96.73%of oil extraction rate and97.69%phospholipid extraction rate, while the load of n-butyl alcohol extraction was also reduced with simultaneous extraction of oil and phospholipid. Therefore, the "cold pression-n-butyl alcohol extraction" is a promising green processing technology.3. The mechanism of methoxycarbonyl bio-diesel catalytically produced from Swida wilsoniana oil by CRL was studied in this work.①Porous magnetic polymer particles with epoxy group were produced for immobilized enzyme with particle diameter4μm. The surface of particles was porous with uniform distribution.②The immobilization condition of lipase was optimized with GHD(40) as carrier:lipase125mg/g, immobilization time7h, enzyme absorption118.5mg·-1, specific enzyme acitivity7.56×105U/g, and activity recovery0.95.③Three kinds of immobilized CRL with different epoxide number were made. The adsorption isotherm line was fitted by Langmiur equation of monomolecular layer, which correlation coefficient was higher than0.99. The effects of epoxide number and temperature on adsorption of Swida wilsoniana oil were researched. The fitting pseudo-second-order kinetic equation was built up with correlation coefficient higher than0.99. And for the oil of Swida wilsoniana, the surface of the immobile lipase has30.44kJ/mol activation energy of adsorption.④Compared with isolated enzyme, the optimal reaction temperature of interesterification catalyzed by immobilized enzyme was enhanced from37℃to42℃, while optimal pH was increased from7.2to7.5. After recovering12times, the acitivity of immobilized enzyme was kept over92%. However, the similar catalyzing trends were found between immobilized and isolated enzymes. That trend was shown as increasing in the initial process and then decreasing with moisture increasing.⑤As depicted by GC-MS, The main compounds in Swida wilsoniana oil methyl ester were methyloleate (50.61%), methyl hexadecanoate (14.74%), and methyl stearate (7.11%). Therefore, methyl ester from Swida wilsoniana oil should be a potential substitute for conventional fossil diesel.4. The catalytic pyrolysis of Swida wilsoniana oil into rich-alkyl bio-oil by alkalinity catalyst was carried out in this research. The results were described as follows:CD The composite catalysts were composed of adding KF into CaO. The lamellar structure with porosity was clearly imaged by SEM. Its specific area was enhanced significantly compared with CaO. As shown by XRD analyses, neutralization of basic sites during addition of KF was inhibited, resulting in increasing catalyst’s activity and stability.②The optimal condition in KF/CaO runs were catalyst1.0%, temperature494.2℃, and reaction68.6min, in which the liquid yield reached upwards of84.0%.③There are several kinds of carboxylic acids in The pyrolysis products have several kinds of carboxylic acids resulting a high acid value. Therefore, ionic liquid [Hnmp]+HSO4-was applied as fine catalyst in order to reduce acid value of product in this study. After that treatment, the rich-alkyl bio-oils with good quality were obtained. The highest esterification rate was shown as95.7%. In addition, the total esterification rate could be kept as over90%after recovering6times. The optimal condition was alcohol/oil rate30%, reaction temperature75℃, reaction time100min, and catalyst additive2.0%.5. Based on the principle of eco-energy value and the input-output model, the energy life cycle analysis for biofuel from Swida wilsoniana fruits was carried out. The results showed that, before allocating co-product value, the net energy value (NEV) of carbomethoxy and rich hydrocarbon biofuel were31593.38MJ/ha and36924.16MJ, and the fossil energy ratio (FER) were3.94and6.71, respectively.And if conside the co-product value, the net energy value (NEV) of carbomethoxy and rich hydrocarbon biofuel were98453.66MJ/ha and99121.2MJ/ha, and the fossil energy ratio (FER) were4.52and7.17, respectively. And the results further demonstrated that both the carbomethoxy and the rich hydrocarbon biofuel from Swida Wilsoniana fruits have positive energy efficiency, and can save some of the fossil fuel. But from the standpoint of energy efficiency, the hydrocarbyl-rich biofuel is more competitive. Compared with the conventional transesterification technology, the catalytic pylolysis technology is more suitable for the conversion of biofuel. The research results provided some information for us to choose the emergy product or techonology which is more effective. |
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