An economic and effective method of preparing enriched 10B boric acid was established by chemical reactionof enriched 10BF3 and CaCO3. A process of boron trifluoride reacting with water was investigated under certainc...An economic and effective method of preparing enriched 10B boric acid was established by chemical reactionof enriched 10BF3 and CaCO3. A process of boron trifluoride reacting with water was investigated under certainconditions. Calcium carbonate was selected to counteract hydrofluoric acid followed on. Some key operation factorswere investigated, such as temperature, reaction time and the ratio of CaCO3 to 10BF3. The results showed that the yieldof enriched 10B boric acid could reach 97. 2% and the purity was up to 94. 1% under the following conditions： the temperaturewas 50-60,℃, the reaction time was 28 h and the ratio of CaCO3 to 10BF3 was 4. In addition, after recrystallizationand titration analysis, the purity of the product could reach over 99. 2% from 94.1%.展开更多
Poly-α-olefin(PAO) synthetic oil is the base oil of high-quality lubricants, and has a huge market potential.We illustrate PAO synthesis by catalytic polymerization of 1-decene with a boron trifluoride(BF_3)/alcohol ...Poly-α-olefin(PAO) synthetic oil is the base oil of high-quality lubricants, and has a huge market potential.We illustrate PAO synthesis by catalytic polymerization of 1-decene with a boron trifluoride(BF_3)/alcohol system. Gas chromatography–mass spectrometry, proton nuclear magnetic resonance and ^(13) C nuclear magnetic resonance analysis confirmed dimer, trimer and tetramer structures of PAO. Each component contained branched chains with a 1,2 insertion of a head-to-tail link; a 2,1 insertion of a tail-to-tail link and a methyl-containing linked structure. At a low conversion rate, the reaction rate was related directly with the reaction temperature and the catalyst/1-decene concentration. An apparent kinetic equation for PAO formation was determined during 1-decene polymerization.展开更多
Because of the superior features of boron-10 isotope in absorbing hot neutrons, boric-10 acid(H310BO3)has been used widely in nuclear industry. Boric-10 acid is obtained from boron-10 trifluoride(10BF3) by esterificat...Because of the superior features of boron-10 isotope in absorbing hot neutrons, boric-10 acid(H310BO3)has been used widely in nuclear industry. Boric-10 acid is obtained from boron-10 trifluoride(10BF3) by esterification and hydrolyzation. In this study, trimethyl borate-10 [(CH3O)310B] was prepared from boron-10 trifluoride(10BF3)through chemical exchange rectification. In addition, the hydrolyzation of trimethyl borate-10 was investigated with different p H values, temperatures and molar ratios of water to trimethyl borate-10. Under the optimum process conditions, high yield of boric-10 acid with nuclear industrial purity grade was realized.展开更多
Fatty acid methyl ester (FAME) preparation is an important step to determine fatty acid composition of oils and fats. Transesterification with boron trifluoride (BF3) in methanol has been widely used;however, the tran...Fatty acid methyl ester (FAME) preparation is an important step to determine fatty acid composition of oils and fats. Transesterification with boron trifluoride (BF3) in methanol has been widely used;however, the transesterification of triacylglycerols usually involves a long heating time, whereas much shorter reaction times may be sufficient when microwave irradiation is used. The purpose of this paper was to optimize FAME preparation with BF3 by microwave irradiation. A three-factor central composite routable (CCRD) design was used to study the effect of the heating time (A), irradiation power (B), and volume of sodium hydroxide (C) on FAME concentration. A second-order polynomial model was employed to generate a surface response. Optimum conditions obtained for FAME preparation were time of 60 s, irradiation power of 220 W, and base volume of 1.5 mL. Compared to conventional methods, the advantages of this method are the quick result and the accuracy.展开更多
基金Supported by the Independent Innovation Fund of Tianjin University(No.1307)
文摘An economic and effective method of preparing enriched 10B boric acid was established by chemical reactionof enriched 10BF3 and CaCO3. A process of boron trifluoride reacting with water was investigated under certainconditions. Calcium carbonate was selected to counteract hydrofluoric acid followed on. Some key operation factorswere investigated, such as temperature, reaction time and the ratio of CaCO3 to 10BF3. The results showed that the yieldof enriched 10B boric acid could reach 97. 2% and the purity was up to 94. 1% under the following conditions： the temperaturewas 50-60,℃, the reaction time was 28 h and the ratio of CaCO3 to 10BF3 was 4. In addition, after recrystallizationand titration analysis, the purity of the product could reach over 99. 2% from 94.1%.
基金supported by the Natural Science Foundation of China(21576048)the PetroChina Innovation Foundation(2014D-5006-0503)
文摘Poly-α-olefin(PAO) synthetic oil is the base oil of high-quality lubricants, and has a huge market potential.We illustrate PAO synthesis by catalytic polymerization of 1-decene with a boron trifluoride(BF_3)/alcohol system. Gas chromatography–mass spectrometry, proton nuclear magnetic resonance and ^(13) C nuclear magnetic resonance analysis confirmed dimer, trimer and tetramer structures of PAO. Each component contained branched chains with a 1,2 insertion of a head-to-tail link; a 2,1 insertion of a tail-to-tail link and a methyl-containing linked structure. At a low conversion rate, the reaction rate was related directly with the reaction temperature and the catalyst/1-decene concentration. An apparent kinetic equation for PAO formation was determined during 1-decene polymerization.
基金Supported by the Independent Innovation Fund of Tianjin University(No.1307)
文摘Because of the superior features of boron-10 isotope in absorbing hot neutrons, boric-10 acid(H310BO3)has been used widely in nuclear industry. Boric-10 acid is obtained from boron-10 trifluoride(10BF3) by esterification and hydrolyzation. In this study, trimethyl borate-10 [(CH3O)310B] was prepared from boron-10 trifluoride(10BF3)through chemical exchange rectification. In addition, the hydrolyzation of trimethyl borate-10 was investigated with different p H values, temperatures and molar ratios of water to trimethyl borate-10. Under the optimum process conditions, high yield of boric-10 acid with nuclear industrial purity grade was realized.
文摘Fatty acid methyl ester (FAME) preparation is an important step to determine fatty acid composition of oils and fats. Transesterification with boron trifluoride (BF3) in methanol has been widely used;however, the transesterification of triacylglycerols usually involves a long heating time, whereas much shorter reaction times may be sufficient when microwave irradiation is used. The purpose of this paper was to optimize FAME preparation with BF3 by microwave irradiation. A three-factor central composite routable (CCRD) design was used to study the effect of the heating time (A), irradiation power (B), and volume of sodium hydroxide (C) on FAME concentration. A second-order polynomial model was employed to generate a surface response. Optimum conditions obtained for FAME preparation were time of 60 s, irradiation power of 220 W, and base volume of 1.5 mL. Compared to conventional methods, the advantages of this method are the quick result and the accuracy.
