Study On The CaO Catalyst Coating For Production Biodiesel By Trans-Esterification

The whole world is now facing the lack of fossil energy caused by energy shortage and environment pollutions. Thus all the countries are actively looking for a renewable alternative energy to replace the fossil energy. Biodiesel as an environmental biomass fuel has got the attention of the countries all over the world. It’s the production of natural oils and alcohols after transesterification. Biodiesel is a clean and renewable energy with lots of characteristics, such as high oxygen content, low sulfur and aromatics, good fluidity at low temperature, high flash point, and good degradability as well.So far, the development of biodiesel is still restricted by its production process. As for the reactor, heat and mass transfer effect of the traditional reactors are poor; while the produc-tion of new reactors is very small which leads to the difficulty of industrial magnification Be-sides, homogeneous catalyst for the preparation of biodiesel product can cause large amounts of waste water during the washing and post-processing period, which may lead to severe en-vironmental pollution. Compared with homogeneous catalyst, the activity of heterogeneous catalyst is comparatively low, and the post process is also complicated.This paper puts the catalyst coating on the lining of Fe-Cr-Al alloy. In order to get CaO load on γ-Al2O3heterogeneous catalyst, BET, XRD, XPS, FTIR techniques were used to study the character of catalyst carrier and active component. The preparation process are as follows:first, the γ-Al2O3is put into nitric acid, magnetic stir was continuously done to get serous form, then active component Ca (NO3)2-4H2O was added, after a second magnetic stir, the gel was formed, Thus coating the gel on Fe-Cr-Al alloy lining, after desiccation and cal-cinations, the heterogeneous catalyst with CaO load on γ-Al2O3was got. Then the catalyst coating was put into the GSH-25reactor, put to produce biodiesel. After optimization of the experimental parameters by using the response surface method, we got the best process con-ditions are as follows:oil alcohol mole ratio being11.6, the reaction temperature being407.6K, the reaction time being4.4h. When we substituted these parameters into the regression equation, the biodiesel production yield was94.8%. This result was both verified by experi-ment and theoretical estimation, the error was less than4%.