Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying t...Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying to obtain ruthenium trichloride,nitrosation and hydrolysis to obtain ruthenium nitrosyl hydroxide,removing of K^(+)and Cl^(-),and neutralization with nitric acid.The effects of temperature,concentration,time and pH on the yield and purity of intermediates and final product were studied,and the optimum process conditions were obtained.The yield of ruthenium nitrosyl nitrate is 92%,the content of ruthenium in high purity product is 32.16%,and the content of Cl^(-)and K^(+)are much less than 0.005%.The reaction kinetics of ruthenium nitrosyl chloride to ruthenium nitrosyl hydroxide was studied.The reaction orders of Ru(NO)Cl_(3)at 40,55 and 70℃are 0.39,0.37 and 0.39,respectively,while those of KOH are 0.16,0.15 and 0.17,respectively.The activation energy is-2.33 k J/mol.展开更多
A method for preparing D-valine from L-valine by racemization and chemical resolution is presented. The resolving reagent, D-2,3-dibenzoyl tartaric acid was obtained by hydrolyzation of D-2,3-dibenzoyl tartaric anhydr...A method for preparing D-valine from L-valine by racemization and chemical resolution is presented. The resolving reagent, D-2,3-dibenzoyl tartaric acid was obtained by hydrolyzation of D-2,3-dibenzoyl tartaric anhydride prepared by reaction of benzoyl chloride with D-tartaric acid. DL-valine was prepared by racemization of L-valine in the presence of aldehyde in a medium of acetic acid at 100 to 110°C for 3 h. In the presence of mineral acid, reaction of D-2,3-dibenzoyl tartaric acid with DL-valine formed diastreroisomeric salts at 84 to 95°C. Salt composed of D-2,3-dibenzoyl tartaric acid and D-valine precipitated when the diastreroisomeric salts mixtures were cooled to 15°C. The salt was reacted with base giving D-valine with yield of 70% to 80% and optical purity of over 98%.展开更多
The viscosities of pure water,the acetic acid+water binary system,and the p-xylene+acetic acid+ water ternary system at different concentrations were determined with a rolling-ball viscometer at temperatures from 313....The viscosities of pure water,the acetic acid+water binary system,and the p-xylene+acetic acid+ water ternary system at different concentrations were determined with a rolling-ball viscometer at temperatures from 313.15 to 473.15 K and pressures from 0.10 to 3.20 MPa.The viscosity data were fitted by a correlation equation for the estimation of the mixture viscosities.The average absolute deviations(AAD)of the correlation for binary and ternary systems are 2.48%and 1.77%,respectively.展开更多
Self-made enriched IUB boric acid as raw material was purified by recrystallization. The effects of final crystallization temperature, crystallization time, stirring speed, crystallization frequency and other factors ...Self-made enriched IUB boric acid as raw material was purified by recrystallization. The effects of final crystallization temperature, crystallization time, stirring speed, crystallization frequency and other factors on the purity were investigated. The appropriate operating condition was that the final crystallization temperature and time were 5 ℃ and 10 h respectively under a low-speed stirring for crystallizing twice, which would make the purity and yield of boric acid reach 99.94% and 95.36%, respectively. Taking this as foundation, recrystallization process was optimized with acetone as anti-solvent, whose amount was the most important index. The boric acid solution was added into acetone and recrystallized under the same condition, and the purity and yield of boric acid would reach 99.98% and 99.61%, respectively. The product detected by XRD was confirmed as boric acid crystal. Main ion concentration in the product was detected by ICP, which basically met the national standard of high purity. Crystal morphology of boric acid was observed by SEM.展开更多
基金Project(22178392)supported by the National Natural Science Foundation of China。
文摘Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying to obtain ruthenium trichloride,nitrosation and hydrolysis to obtain ruthenium nitrosyl hydroxide,removing of K^(+)and Cl^(-),and neutralization with nitric acid.The effects of temperature,concentration,time and pH on the yield and purity of intermediates and final product were studied,and the optimum process conditions were obtained.The yield of ruthenium nitrosyl nitrate is 92%,the content of ruthenium in high purity product is 32.16%,and the content of Cl^(-)and K^(+)are much less than 0.005%.The reaction kinetics of ruthenium nitrosyl chloride to ruthenium nitrosyl hydroxide was studied.The reaction orders of Ru(NO)Cl_(3)at 40,55 and 70℃are 0.39,0.37 and 0.39,respectively,while those of KOH are 0.16,0.15 and 0.17,respectively.The activation energy is-2.33 k J/mol.
文摘A method for preparing D-valine from L-valine by racemization and chemical resolution is presented. The resolving reagent, D-2,3-dibenzoyl tartaric acid was obtained by hydrolyzation of D-2,3-dibenzoyl tartaric anhydride prepared by reaction of benzoyl chloride with D-tartaric acid. DL-valine was prepared by racemization of L-valine in the presence of aldehyde in a medium of acetic acid at 100 to 110°C for 3 h. In the presence of mineral acid, reaction of D-2,3-dibenzoyl tartaric acid with DL-valine formed diastreroisomeric salts at 84 to 95°C. Salt composed of D-2,3-dibenzoyl tartaric acid and D-valine precipitated when the diastreroisomeric salts mixtures were cooled to 15°C. The salt was reacted with base giving D-valine with yield of 70% to 80% and optical purity of over 98%.
基金Supported by China Petrochemical Corporation(X505012)
文摘The viscosities of pure water,the acetic acid+water binary system,and the p-xylene+acetic acid+ water ternary system at different concentrations were determined with a rolling-ball viscometer at temperatures from 313.15 to 473.15 K and pressures from 0.10 to 3.20 MPa.The viscosity data were fitted by a correlation equation for the estimation of the mixture viscosities.The average absolute deviations(AAD)of the correlation for binary and ternary systems are 2.48%and 1.77%,respectively.
文摘Self-made enriched IUB boric acid as raw material was purified by recrystallization. The effects of final crystallization temperature, crystallization time, stirring speed, crystallization frequency and other factors on the purity were investigated. The appropriate operating condition was that the final crystallization temperature and time were 5 ℃ and 10 h respectively under a low-speed stirring for crystallizing twice, which would make the purity and yield of boric acid reach 99.94% and 95.36%, respectively. Taking this as foundation, recrystallization process was optimized with acetone as anti-solvent, whose amount was the most important index. The boric acid solution was added into acetone and recrystallized under the same condition, and the purity and yield of boric acid would reach 99.98% and 99.61%, respectively. The product detected by XRD was confirmed as boric acid crystal. Main ion concentration in the product was detected by ICP, which basically met the national standard of high purity. Crystal morphology of boric acid was observed by SEM.
