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Biodiesel as a green renewable energy, no sulfur and aromatics, high flash point, and lubricating properties, biodegradable. Currently, in industrial production, mainly through homogeneous acid or base catalyzed esterification or transesterification reaction of biodiesel, with fast response, high conversion rate, etc., but there is much waste, catalyst separation difficult, complex process shortcomings . Solid acid or base as a catalyst for biodiesel, not only can avoid the traditional problem of homogeneous catalytic process, but also has mild reaction conditions, the catalyst can be reused, easy to use automated continuous production, no corrosion of equipment, environmental pollution and so on. Therefore, this study proposes a solid acid, alkali as catalyst for biodiesel. Through this paper commonly used solid acid catalyst system filter, the initial gain in biodiesel and biodiesel feedstock pretreatment preparation of high activity SO42-/ZrO2 solid super acid, carbon-based solid acid and barium oxide solid base. This study will be a solid acid catalyst and in the preparation of the application of bio-diesel as the research object, focusing on common solid acid catalysts were screened and studied catalyst preparation conditions and the process to solve the current problems of heterogeneous catalysts and the solid catalyst biodiesel in applied research, to be its optimum application conditions, as a solid acid catalyst in the promotion of bio-diesel production basis. The results are as follows: (a) preparing a solid superacid catalyst SO42-/ZrO2 optimal conditions: ZrOCl2 solution and 28% concentrated ammonia under ultrasonic irradiation aging 3h, at room temperature for 24h, washed by deionized water into thermostatic oven drying, fine, obtain a precursor ZrO2; ZrO2 in 2mol · L-1, H2SO4 solution impregnated 24h, calcined at 550 ℃ under the conditions of 4h. The catalyst in the traditional esterification deacidification of optimum application conditions: SO42-/ZrO2 amount of 2.5% of raw material quality, the amount of methanol, 45% of raw material quality, oil bath temperature of 100 ℃, reaction time 4h, transforming rate of 92.83%, catalyst can be reused five times, the esterification rate is still higher than 75%; watershed of the catalyst in the distillation vapor esterification deacidification of optimum application conditions: SO42-/ZrO2 amount of catalyst 4 %, oil bath temperature 100 ℃, gasification temperature 85 ℃, reaction time 3.5h, conversion rate of 97.81%, catalyst can be reused five times, the conversion rate was 36.56%. The results showed that: Distillation Gas Manifold high acid esterification process is more suitable for biodiesel feedstock drop acid, and the catalyst reaction after separation, washing and drying to continue participating in the reaction can extend the life of the catalyst. (2) Preparation of carbon-based solid acid optimal conditions: mass ratio of 25:6 starch and p-toluenesulfonic acid were dissolved in distilled water fever in a muffle furnace 200 ℃ temperature carbonization 10h, cooled to room temperature, ground to a 60 mesh powder. The catalyst in the esterification deacidification processes in the optimum application conditions: methanol to oil mass ratio 1:4, catalyst dosage 6.5%, oil bath temperature 100 ℃, reaction time 6h, conversion rate of 80.21%, catalyst can be reused five times, the conversion rate of 70%. The results showed that: although the catalyst has good stability, but not high activity limits its application (3), barium oxide Catalysts optimal conditions for preparing: Ba (OH) 2.8 H2O was calcined at 450 ℃ conditions 4h, cooled to room temperature in a mortar spare finely desiccator. Transesterification reaction in the conventional process of optimum application conditions: the amount of raw material quality barium oxide 0.9%, the amount of methanol for 30% of raw material quality, oil bath temperature of 70 ℃, reaction time 2.5h, conversion rate was 96.82 % catalyst can be reused 3 times, the conversion rate is still higher than 83%; ester exchange process in the gas phase of the optimum application conditions: amount of catalyst is 1.1%, the oil bath temperature of 65 ℃, reaction time 1.5h, gasification temperature 90 ℃, conversion was 96.31%, catalyst can be reused 5 times, the ester exchange rate of 62%. The results showed that: barium oxide, solid base catalyst and catalytic mechanism of KOH as catalyst, and the catalyst after the reaction was separated, washed and dried in the reaction to continue to extend the life of the catalyst.
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