| As a kind of renewable energy sources, biodiesel can not only relieve environmental pollution problems caused by the use of fossil fuels in large scale modern industry, but can reduce the impacts caused by the "oil crisis" to modern economic in the world. At present, the biodiesel production in China is of its drawbacks with outdated processes technologies, low production process efficiency and seriously raw material shortage. Those cause a very high level of biodiesel production cost. To solve these issues above, our research group submits a research Application Form, which named "Research on the conversion of biodiesel from special sunflower oil ", to Hebei Provincial Science and Technology Agency, and successfully got the financial support with the project. (Issue number: 09277103D). After that, two kinds of special designed sunflower seed are imported from Romania. It is of high oil content and good biodiesel production features. Prof. Wei Jingfang had successfully plant it in HeBei province and made of its seed oil. With this oil, the biodiesel production process is studied in this paper for the first time and also provides a solid fundamental research for the following pilot plant research in its optimization process parameters.The paper firstly emphasizes on the production process by two kinds of sunflower oil. Firstly, according to our national standards, the oil’s nature has been texted. Results show that a good consistent with national standards. Comparing with the palm oil, the water contents of that oil have obvious advantages. Therefore, two kinds of raw material are both good raw material for biodiesel. Secondly, According to the nature of raw materials selection and experimental design requirements, we select the sodium methoxide as a catalyst of transesterification. The single factor experiments about the NO.1 oil and the NO.2 oil have been made. It considered the following aspects:the molar ratio of methanol to oil; the amount of sodium methoxide; Reaction time and the temperature. It is the basis for establishing the level of orthogonal factors. Orthogonal test have been made. The results show us the optimum reaction conditions. The production rate of the NO.1 oil was 94.5% and the production rate of the NO.2 oil was 93.1%. Highest transesterification rate was obtained when 0.5wt% of sodium methoxide was used in the reaction mixtures containing the molar ratio of methanol to oil with 8:1 at 67℃for 60 minutes. Compared with other vegetable oil, this reaction needs to be optimized because of the high ratio of alcohol to oil. Optimum conditions:Lower alcohol to oil ratio to 6:1. By separating out the method of glycerol, we improve the reaction yield. Corresponding yield of two materials are 95.7%、94.3%, which are slightly increased before optimization. Biodiesel nature is determined in accordance with national standard and the results meet the standards. Comparing the feedstock nature, the yield of transesterification and bio-diesel oil quality, the results show that the 1st fuel oil is more suitable for biodiesel production than the 2nd.In order to reduce biodiesel production cost. optimization of washing conditions is needed. Through the single factor experiments, the optimum conditions have been obtained as follows:the quality ratio of water to biodiesel is 30%, washing temperature is 50℃, washing times is at least 3. After the washing process, the content of glycerol will less than 0.02%. It is achieve the standards of biodiesel in our country. At the same time, we had purified glycerol as by-product of biodiesel. And the relative technique and process parameters had been studied. It is found that the purity of refined glycerol could reach up to 96.8% in the follows condition:crude glycerol was diluted with methanol, then was neutralized to pH= 5.0～6.0 with phosphate. The temperature of vacuum distillation was between 184～204℃. |
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