In the study, the epoxidation process of soybean oil by microflow system (MFS) was investigated. With formic acid as oxygen carrier and EDTA-2Na as stabilizer, the optimal result (epoxidized soybean oil (ESO) with an epoxy number (EN) of 7.3) was obtained in such conditions: temperature 75 °C, H2SO4 concentration 3%, EDTA-2Na dosage 3%, residence time 6.7 min, ratio of formic acid to hydrogen peroxide 1:1, and H2O2 to double bond molar ratio 8:1.

No abstract

During the lactide producing process, volatile impurities, such as lactic acid and its dimer, are simultaneously distilled out with lactide. To remove these impurities, many post-treatments were needed. Herein, we present a novel approach to obtain high purity lactide by adding high-boiling-point alcohols to immobilize these volatile impurities. A series of high-boiling-point alcohols were screened and pentaerythritol was found to be the best immobilization reagent. When the molar ratio of lactic acid’s carboxylic group and pentaerythritol’s hydroxyl group was 15:1, lactide with 99% GC purity was directly distilled out and no traces of lactic acid and its dimer were detected. The results of HPLC-MS revealed that the distillation residues were esters of pentaerythritol with lactic acid or its oligomer. This indicated that volatile impurities were immobilized in distillation residues. The distillation residues were reused for 4 runs, and the purities of lactide were all over 98%.

Key indicatorsSingle-crystal X-ray study T = 293 K Mean (C-C) = 0.004 Å R factor = 0.061 wR factor = 0.192 Data-to-parameter ratio = 14.1 For details of how these key indicators were automatically derived from the article, see

Key indicators: single-crystal X-ray study; T = 298 K; mean (C-C) = 0.003 Å; R factor = 0.046; wR factor = 0.130; data-to-parameter ratio = 14.6.In the molecule of the title compound, C 9 H 8 ClNO 4 , an intramolecular C-HÁ Á ÁO hydrogen bond results in the formation of a planar five-membered ring, which is nearly coplanar with the adjacent six-membered ring, the rings being oriented at a dihedral angle of 4.40 (3) . In the crystal structure, intermolecular C-HÁ Á ÁO hydrogen bonds link the molecules. Related literature ExperimentalCrystal data