Studies On The Methods Of Harvesting Phaeodactylum Tricornutum And Extracting Tridglyceride

Biodiesel is clean renewable energy and good substitutes for petroleum diesel,but the raw materials supply and cost constraints are always important factors in the development of biodiesel industry.As one model of diatom and one type of excellent economy microalgae,Phaeodactylum tricornutum has great exploitation and utilizing potential.There are a lot of researches about the factors which affect the cell growth, propagation,the biochemical composition,PUFA accumulation and so on.But the studies that using Phaeodactylum tricornutum to produce biodiesel is few.It can accumulate triglycerides in the logarithmic phase growth,so that it can provide raw materials for biodiesel synthesis.How to find one method of collecting algal cells which is simple,fast and low-cost and can be used in large-scale is the most important problem, and the extraction of the triglyceride contained is also the key of the study.These two aspects are very important part of the study and are also very difficult studies.The content and result of the paper are as follow.In this thesis,Phaeodactylum tricornutum growth and triglyceride content affected by temperature were studied to determine the optimal culture temperature.The result shows that 20℃is the optimum temperature,while the content of triglyceride is not affected.On the basis of summarizing the method of harvesting microalgae current commonly used,we explored the method to harvest Phaeodactylum tricornutum cosmically,and found a fast,easy,cheap method,which adopts the method of flocculating algal cells.We focused on several flocculants on the flocculation efficiency of algal cells,and ultimately optimized the method of using of ferric chloride and organic polymer anionic polyacrylamide flocculants AGEFLOC WT652 combined.It is suitable for large-scale applications,so it provides a theoretical foundation for Phaeodactylum tricornutum harvesting of large-scale farming.Furthermore,we combined the comprehensive analysis of the literature research and the research conditions of the laboratory can provide,we used soxhlex extraction and ultrasonic-assisted extraction methods to extract triglyceride contained in Phaeodactylum tricornutum cells.The results shows that the method of ultrasound-assisted extraction is better and the extraction efficiency can achieve 27%of cell dry weight.