| Considering the double crisis of energy and environment, it is urgent to carry out studies on the transformation and utilization of bioenergy. Jatropha curcas L. is one of the representative diesel plants in the world. It has great application potential and market prospect for non-edible Jatropha oil to produce biodiesel. The paper produced biodiesel using Jatropha oil as the raw material, and systematically studied the influences of catalysts, catalyst preparations, catalytic processes and performances, and other influence factors. Bamboo has the advantages of inexpensive cost, widespreadly distribution and rapid regeneration. In the paper, bamboo chars were prepared through the thermochemical treatment of bamboo powder, and the obtained chars were then used as carrier for synthesizing carbon-based solid acid. The solid acid was used in the catalytic esterification and transesterification of high-acid-valued lipid. Magnetic Ni-based solid base catalyst was synthesized with the assistance of the reducibility of bamboo chars, and was used in the catalytic transesterification of refined lipid. A continuous two-step process, including the catalytic esterification with bamboo carbon-based solid acid and the catalytic transesterification with magnetic Ni-based solid base, was proposed for transforming Jatropha oil to biodiesel, and improved its transformation efficiency.Pyrolysis and hydrothermal method were introduced and compared in the preparation of bamboo char through carbonization, and the physical properties of obtained chars were investigated. Pyrolysis chars were prepared at 300-400℃ for 0.5 or 1 h, while hydrothermal chars were produced at the conditions of 300-370℃,0.5 or 1 h. The results showed that the yields of pyrolysis chars were in the range of 32.40-48.00%, which was higher than that of hydrothermal chars (31.26-43.68%). Pyrolysis chars had special morphology of vascular bundles and porous surfacce, while numerous carbonaceous spheres of micron size and multi-hollow structure were observed over the surface of hydrothermal chars. The BET surface areas of pyrolysis and hydrothermal chars were both low, but pyrolytic chars had larger pore size of 13-17nm. Thermo-gravimetry (TG) experiments of chars showed the thermal stability of pyrolysis chars remarkably improved with the increase of carbonization temperature and the prolonging of carbonization time. Considering the char yields and the pore size of chars, pyrolytic chars exhibited better ability to be a catalyst carrier.The pyrolysis and gasification kinetics of bamboo powder were investigated in TG experiments under CO2 atmosphere, using Satava-Sestak model function method. The results showed that bamboo powder mainly ran through four stages as the promotion of carbonization temperature, namdly glass transition stage (100-200℃), cellulose and hemicellulose pyrolysis stage (200-400℃), lignin pyrolysis stage (400-810℃) and char gasfication stage (810-900℃). The aromatic and graphite transition of char occurred during lignin pyrolysis stage. Thus, in order to obtain complete carbonization of bamboo powder, the pyrolysis temperature should be higher than 400℃. In addition, for the last three pyrolysis stages, the active energies calculated by Satava-Sestak model function method were in the range of 164.10-189.98 kJ/mol,13.91-19.10 kJ/mol and 178.02-226.57 kJ/mol, respectively.Carbon-based solid acids were prepared through the sulfonation of pyrolysis char in high temperature sulfuric acid, and the catalytic activities of solid acids in esterification and transesterification of high-acid-valued lipid was evaluated. The esterification of oleic acid was chosen as reference reaction. The single factor experiments gave the conditions of preparing bamboo carbon-based solid acid with the highest catalytic activity, which were carbonization temperature of 650℃, carbonization time of 6h, sulfonation temperature of 140℃ and sulfonation time of 10h. Carbon-based solid acid had the structure of aromatic carbon with the specific surface of 8.58 m2/g. The solid acid could endure high temperature of 200℃. NH3-TPD test demonstrated that two absorption peaks were both existed, which corresponded to weak and strong acid sites. The sulfonic acid density was calculated to be 1.9 mmol/g by elemental analysis. The bamboo carbon-based solid acid was used in the one-pot transesterification of Jatropha oil to biodiesel. At the reaction temperature of 200℃, reaction time of 5h, methanol/oil mole ratio of 12:1 and catalytic amount of 5%, the biodiesel yield was 71.67%. Because of the low biodiesel yield and serious catalytic deactivation, the repeated use of carbon-based solid acid catalyst should be further improved.New magnetic solid base catalysts were synthesized by magnetic nickel supporting cheap active compound sodium silicate. The transesterification of refined oil (soybean oil) was used as the reference reaction for evaluating the preparation and catalytic performance of magnetic solid base. The transesterification ratio reached 98.46% at the optimized reaction conditions. The catalyst could be recycled with magnet after reactions, and the catalytic activity was still higher than 93% when the magnetic solid base reused for four times. The leaching of active species was believed to be responsible for the loss of catalytic activity.Finally, a two-step course for continuous producing biodiesel from Jatropha oil with high acid value was developed. The combined courses included two steps, namely reaction with bamboo carbon-based solid acid and reaction with magnetic solid base. (1) As the result of optimization, the acid value of Jatropha oil was reduced from 17.13 mg KOH/g to 1.71 mg KOH/g with the esterification ratio of 90.02% under the conditions including reaction temperature of 100℃, reaction time of 60 min, methanol/oil molar ratio of 12:1 and carbon-based solid acid dosage of 7%. (2) The transesterification of pretreated Jatropha oil with less acid value was catalyzed by magnetic solid base. The biodiesel yield reached 90.44% under the conditions including reaction temperature of 65℃, reaction time of 60 min, methanol/oil molar ratio of 9:1 and magnetic solid base dosage of 7%. (3) Within the temperature range of 45-65℃, a first-order kinetic model was used for the study of the reaction kinetics in Jatropha oil transesterification. The results showed that the activate energy was 23.85 kJ/mol, and constant frequency was 252.45/min. (4) After esterification, carbon-based solid acid was separated by simple centrifugation from products. After transesterification, magnetic solid base was recycled with magnet. The pretreated Jatropha oil with less acid value could be directly used in the transesterification reaction without other treatments. Compared with conventional liquid catalysts, the solid catalysis process used here had the advantages of mild reaction conditions, simple operation, easily recycle of products and the reuse possibilities of catalyst.
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