Design Of Fuel Based On Cold Filter Point Of Biodiesel

Biodiesel has attracted worldwide attention for its renewable and environmental characteristics,and the development of biodiesel can alleviate the pressure of energy shortage and environmental pollution to a certain extent,which is helpful to the adjustment of energy structure.However,in the low temperature condition,the high melting point of the biodiesel is easy to crystallize and precipitate,and the fluidity is poor.That affected the popularization and application of biodiesel.The main content of this paper is the design of biodiesel based on the cold filter plugging point(CFPP)of biodiesel,so as to improve the low temperature fluidity of biodiesel,and to accumulate some theoretical and experimental support for the popularization and application of biodiesel.In this paper,the physical and chemical properties of eight kinds of biodiesel made in the laboratory and in the market were determined.Determination of biodiesel components by GC-MS,the results show that the main chemical components of biodiesel are long chain fatty acid methyl ester(FAME),which is composed of three elements of C,H and O,including saturated fatty acid methyl esters(SFAME,C14:0?C22:0)and unsaturated fatty acid methyl ester(UFAME,C16:1?C20:1,C18:2,C18:3).Different chemical biodiesel raw material for the preparation of different components,the CFPP and kinematic viscosity also have large differences,the CFPP highest of eight kinds biodiesel is Palm oil methyl ester(PME),the CFPP minimum of eight kinds biodiesel is Rapeseed oil methyl ester(RME).The kinematic viscosity of biodiesel with longer carbon chain SFAME was higher.The content of SFAME in coconut oil methyl ester(CCME)is close to that of No.0 petrol diesel(OPD).The change tendency of the kinematic viscosity of the two oils is similar,and the kinematic viscosity is lower than that of the other seven kinds of biodiesel.The CFPP is lower,the fluidity of biodiesel is better.Through the analysis of the relationship between the chemical composition and the CFPP of biodiesel found thatlong chain SFAME content of biodiesel is higher,the CFPP is higher;the content of short chain SFAME is higher,the CFPP is lower;the content of UFAME is higher,the degree of unsaturation is higher,the CFPP of biodiesel is lower.In this paper,the crystallization mechanism of biodiesel is taken as the theoretical basis,then design of biodiesel fuel based on CFPP.Measures taken include:?Component controlled fuel design.The biodiesel is respectively combined with biodiesel from different raw materials,OPD,-10 petrochemical diesel oil(-10PD),kerosene,ethanol and butanol;High melting point component of SFAME by crystallization separation of biodiesel;and added cold flow improver.The results show that with different fuel hybrid optimization,can reduce the content of SFAME;A large number of small ester crystals were precipitated by adding polar group additives.It is not easy to produce large ester group which affects the low temperature fluidity.The fuel design of the component control can effectively reduce the CFPP of biodiesel.?Molecular control of fuel design.The preparation of biodiesel was replaced by ethanol and butanol,and the fatty acid ethyl ester and fatty acid butyl ester were prepared by ester exchange reaction.The CFPP of the fatty acid ethyl ester and fatty acid butyl ester was lower than that of FAME prepared from the same raw oil.Molecular control optimizes the molecular structure of biodiesel,increases the chain length of the ester group of biodiesel components,and increases the molecular curvature of the components,which hinders the formation of crystals and reduces the CFPP of biodiesel.The highest CFPP is PME in eight kinds of biodiesel,is 10?.Palm oil fatty acid ethyl ester(PEE)and palm oil fatty acid butyl ester(PBE)were prepared from palm oil with ethanol and butanol,the CFPP is 7?and3?,respectively.The CFPP of PME was reduced.