Recently, enzymatic method has been used to prepare biodiesel using various oils. But the high acid value of the biodiesel product using enzyme as a catalyst has been one issue. In this work, an attempt to reduce the acid value of fatty acid ethyl ester (FAEE) product to satisfy the specified requirement (AV ≤ 0.5 mgKOH/g), a complex enzyme-catalyzed method was used for the ethanolysis of Semen Abutili seed oil (SASO) (AV = 5.5 ± 0.3 mgKOH/g). The effects of various variables (constituents of complex enzyme, type and addition of water removal agent, time, temperature, enzyme addition load, substrate ratio) on the enzymatic reaction were investigated. The optimal reaction conditions were: 1% addition of liquid lipase Eversa ® Transform 2.0% and 0.8% of enzyme dry powder CALB, reaction temperature 35°C, alcohol-oil ratio 9:1 (mol/mol), 0.8 g/g of 4A-MS and reaction time 24 h. Under the optimal reaction conditions, the FAEE yield was 90.8% ± 1.5% and its acid value was decreased from 12.0 ± 0.2 mgKOH/g to 0.39 ± 0.10 mgKOH/g. In further evaluating the feasibility of preparing FAEE from SASO, the FAEE products obtained under the optimal reaction conditions were purified and evaluated with reference to the ASTM D6751 standard for the main physicochemical indexes. The results obtained were in accordance with the requirements except for the oxidative stability.
Herein, a series of esteryl-bridged energetic compounds were prepared using a simple and efficient esterification approach. All the compounds were fully characterized by IR spectroscopy, multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, thermogravimetric analysis (TG), and differential scanning calorimetry (DSC). Structures of 1 and 4 were further confirmed by single crystal X-ray diffraction. Energetic performance was evaluated by EXPLO5 based on the measured densities and calculated heats of formation (Gaussian 09). These fluorodinitroethyl esters have good thermal stabilities (190.7–208.3 °C) and high densities (1.81–1.90 g cm−3). Detonation pressures and velocities of 1–5 fall in the range of 27.4–36.6 GPa and 7870–8459 m s−1, respectively. Sensitivity data based on impact and friction tests show that these compounds are insensitive (IS = 27.6–40 J; FS > 360 N). Moreover, two of the representative compounds 1 and 4 exhibit the desired melting points (1: 85.0 °C; 4: 94.7 °C) as the ideal melt cast explosives, relatively high detonation properties (D = 8459, 8196 m s−1; P = 36.6, 29.8 GPa), as well as relatively low sensitivities (IS = 30.5, 27.6 J; FS > 360 N).
The accumulation of waste PET leads to serious environmental problem. PET degradation has been hot topic and is studied by lots of researchers. At present, numerous catalysts have been developed, among which ionic liquid catalyst is attractive due to its excellent advantages like convenient recycling and highly catalytic effect. In this work, a series of ionic liquids based on 1,1,3,3-tetramethylguanidine (TMG) were synthesized and used as catalyst of PET degradation. The influence of different structure of cation and different metal salt on PET degradation were studied. DFT calculation showed that the interaction between the ionic liquid and ethylene glycol can be changed by adjustment of the structure of the cation. At optimal condition, using [C 6 TMG]Cl/2ZnCl 2 as catalyst, PET conversion was 100% and BHET yield was 92.7%. To our best knowledge, this is first report about ionic liquid catalyst of PET degradation with superior BHET yield. Catalytic effect of [C 6 TMG]Cl/2ZnCl 2 did not obviously decrease after it was reused for six times. Moreover, the degradation of commercial beverage bottles was investigated using [C 6 TMG]Cl/2ZnCl 2 as the catalyst, the BHET yield of 84% was obtained, and the quality purity of the product was 90%. In addition, possible mechanism was explored.
危险品化学品经营许可证（带存储）