Study On The Synthesis And Properties Of Lubricant Base Oil For Pentaerythritol Ester

Pentaerythritol fatty acid ester is not only used in industy, such as a dust-proof oil, adhesives, plasticizers, etc, but also widely used in aviation fields as an excellent green lubricant base oil, for its good biodegradability, thermal stability and anti-wear and friction. The branched-chain pentaerythritol ester has more excellent low temperature performance. The low-temperature properties of lubricant base oil can be significantly improved when it mixed with straight-chain esters. Therefore, it become a research hotspot in the synthesis of branched-chain pentaerythritol ester. The difficulties is to choose a suitable catalyst system, because the branched-chain fatty acids is difficult to be carried out fully because of its steric.In the synthesis process of pentaerythritol fatty acid ester, the scholars committed to the choice of catalyst by solvent. Because of the effumability and toxicity of organic solvent it will become harmful to human and environmental factors. In order to meet the requirements of environmental protection, safety, green in modern chemical industry, the pentaerythritol and Isocaprylic acid are taken as raw material to synthesize2-ethyl-,1,1’-[2,2-bis[[(2-ethyl-l-oxohexyl)oxy]methyl]-1,3-propanediyl] ester under solvent-free condition. The optimal operating conditions can be get by the choice of catalysts and the comparing of the the raw materials’s ratio, reaction temperature, reaction time, etc. The optimal esterification conditions were as follows:para-toluenesulfonic acid is the best catalyst with usage amount of2%(w/w) based on the total weight of the raw materials, n(pentaerythritol):n(Isocaprylic acid)=1:5, the reaction was carried out at160"C for5h while the esterification rate of97%was obtained. The structure of the product was determined by FT-IR spectrum. The products have high purity, low color, low acid value. It is an ideal process with simple, low cost, without environment.In addition, the experiment study on the catalytic effect of solid acid catalyst in the synthesis process. The influence of preparation conditions of the catalyst such as, calcination temperature, catalytic property were studied. The flowing Hammett indicator method was used to test the acidity of the catalyst and the catalyst SO42-/TiO2was characterized by means of IR spectra of pyridine adsorbed on the surface. The optimal prepared conditions were as follows:the concentration of H2SO4was1mol/L, the catalyst SO42-/TiO2was calcinated at500℃for3h, while the esterification rate of85%was obtained.