In this work, experimental density data were reported for six fatty acid methyl esters , including methyl butyrate , methyl valerate , methyl caproate , methyl pelargonate , methyl heptanoate , and methyl caprylate . The densities were measured from 293.15 K to 363.15 K and pressures up to 60 MPa by a vibrating-tube densimeter . The relative uncertainty of the measurement is estimated less than 0.001 with a confidence level of 0.95. The high pressure densities were correlated with a Tait-type equation. The overall average relative deviation between experimental data and calculated results from Tait equation for the six fatty acid esters is 0.010%. The derived thermodynamic properties, such as isobaric thermal expansivity and isothermal compressibility , were obtained from the experimental density results. Additionally, for the studied esters, the molecular parameters of the PC-SAFT equation of state were obtained based on the corresponding vapor pressures and liquid densities. The PC-SAFT equation was used to predict the high pressure densities of the esters, and good agreements were observed.
An integrated approach was developed for preparing epoxy fatty acid methyl esters (EFAMEs) from cottonseed using a two-phase solvent extraction (TPSE) process followed by sequential base-catalyzed transesterification and epoxidation reactions. The TPSE process was performed to achieve simultaneous production of high-quality crude cottonseed oil and nontoxic cottonseed meal. The base-catalyzed transesterification of the cottonseed oil proceeded smoothly at 30 °C over 2 h to provide a high yield of fatty acid methyl esters (FAMEs). Subsequent epoxidation of the unsaturated FAMEs using petroleum ether as a non-polar solvent, H 3 PO 4 as a catalyst, 0.3 g/g H 2 O 2 as an oxygen donor, and HCOOH as an oxygen carrier gave the corresponding EFAMEs with a conversion to oxirane of 0.85 g/g. The order of effectiveness of catalysts was found to be H 3 PO 4 > TiO 2 > H 2 SO 4 > strong-acid cation exchange resin. The bio-based integrated process and new methods for the preparation of modified EFAMEs show great promise for comprehensive development and commercial applications of cottonseed with fewer steps and lower cost.
危险品化学品经营许可证（带存储）