This investigation describes the one step preparation of potassium carbonate by electrolysis of potas-sium chloride solution in electrolyzers with various Nation membranes.Potassium bicarbonate solution wasfed to the ...This investigation describes the one step preparation of potassium carbonate by electrolysis of potas-sium chloride solution in electrolyzers with various Nation membranes.Potassium bicarbonate solution wasfed to the cathode compartment,where it was converted into carbonate by reaction with the hydroxideformed at cathode.Because of the low OH^- concentration in the cathode compartment,the back migrationof OH^- through the membrane was almost negligible,resulting in a higher current efficiency,say 90% or more.In this study,electroconductivity,mass transfer,current efficiency and cell voltage were measured.Thefeasibility of the process was discussed and the optimal conditions examined.展开更多
An equation to express ion exchange selectivity coefficient was derived and used for cal- culating that of PPY film with the results obtained by cyclic voltamrnetric measurement.PPY film was synthesized by electrochem...An equation to express ion exchange selectivity coefficient was derived and used for cal- culating that of PPY film with the results obtained by cyclic voltamrnetric measurement.PPY film was synthesized by electrochemical method in aqueous solution using K_4Fc(CN)_6 as supporting electrolyte, and the anions were doped into the film.Ion exchange behaviour of doped Fe(CN)_6^(3-/4-)in the PPY film with Cl^-,NO_3^- or F^- ions in solution has been studied,and the corresponding ion exchange selec- tivity coefficients were determined.展开更多
The rate constants and equilibrium constants of ligand exchange reactions between his (alkylxanthato)palladium(Ⅱ),Pd(S_2COR)_2(R=Am,n-Hex,Bz),and bis(N,N-dialkyldithiocarbamato) palladium(Ⅱ),Pd(S_2CNR_2)_2(K=Et,n-Pr...The rate constants and equilibrium constants of ligand exchange reactions between his (alkylxanthato)palladium(Ⅱ),Pd(S_2COR)_2(R=Am,n-Hex,Bz),and bis(N,N-dialkyldithiocarbamato) palladium(Ⅱ),Pd(S_2CNR_2)_2(K=Et,n-Pr,n-Bu),in chloroform solution have been determined in a temperature range of 20—50°C by means of high-performance liquid chromatography.It was found that both the forward and reverse reactions are of second order.All of the equilibrium constants K determined are 10.3±1.0,much greater than the value(K=4)calculated statistically which indicates that the ternary complexes are more stable than the binary complexes.The experimental results revealed that the reaction rate decreases with the increase in the size of R and R^1 groups and the latter are more remarkable,consistent with the deduction of steric effect.The activation parameters of the reactions have been calculated.In reaction series(11)and(12)(in the text)the isokinetic tempera- tures B=390±8K and β=346±15 K have been observed respectively.A plausiblemechanism in- volving an eight-membered ring intermediate has been proposed on the basis of experimental results.展开更多
(n-Bu_4N)_3W_2Cl_9, prepared from K_3W_2Cl_9, can be readily converted to a series of [W(IV)]cluster compounds,W_3Cl_4(μ-OR)_2(OR')_2(R'OH)_2, including seven known compounds and two newcompounds with R=Me, R...(n-Bu_4N)_3W_2Cl_9, prepared from K_3W_2Cl_9, can be readily converted to a series of [W(IV)]cluster compounds,W_3Cl_4(μ-OR)_2(OR')_2(R'OH)_2, including seven known compounds and two newcompounds with R=Me, R＇=i-Pr and sec-Bu. The crystallographic data of 7 and 8 are herebypresented.展开更多
文摘This investigation describes the one step preparation of potassium carbonate by electrolysis of potas-sium chloride solution in electrolyzers with various Nation membranes.Potassium bicarbonate solution wasfed to the cathode compartment,where it was converted into carbonate by reaction with the hydroxideformed at cathode.Because of the low OH^- concentration in the cathode compartment,the back migrationof OH^- through the membrane was almost negligible,resulting in a higher current efficiency,say 90% or more.In this study,electroconductivity,mass transfer,current efficiency and cell voltage were measured.Thefeasibility of the process was discussed and the optimal conditions examined.
基金This work was financially supported by the National Natural Science Foundation of China.
文摘An equation to express ion exchange selectivity coefficient was derived and used for cal- culating that of PPY film with the results obtained by cyclic voltamrnetric measurement.PPY film was synthesized by electrochemical method in aqueous solution using K_4Fc(CN)_6 as supporting electrolyte, and the anions were doped into the film.Ion exchange behaviour of doped Fe(CN)_6^(3-/4-)in the PPY film with Cl^-,NO_3^- or F^- ions in solution has been studied,and the corresponding ion exchange selec- tivity coefficients were determined.
基金Project supported by the National Natural Science Foundation of China.
文摘The rate constants and equilibrium constants of ligand exchange reactions between his (alkylxanthato)palladium(Ⅱ),Pd(S_2COR)_2(R=Am,n-Hex,Bz),and bis(N,N-dialkyldithiocarbamato) palladium(Ⅱ),Pd(S_2CNR_2)_2(K=Et,n-Pr,n-Bu),in chloroform solution have been determined in a temperature range of 20—50°C by means of high-performance liquid chromatography.It was found that both the forward and reverse reactions are of second order.All of the equilibrium constants K determined are 10.3±1.0,much greater than the value(K=4)calculated statistically which indicates that the ternary complexes are more stable than the binary complexes.The experimental results revealed that the reaction rate decreases with the increase in the size of R and R^1 groups and the latter are more remarkable,consistent with the deduction of steric effect.The activation parameters of the reactions have been calculated.In reaction series(11)and(12)(in the text)the isokinetic tempera- tures B=390±8K and β=346±15 K have been observed respectively.A plausiblemechanism in- volving an eight-membered ring intermediate has been proposed on the basis of experimental results.
文摘(n-Bu_4N)_3W_2Cl_9, prepared from K_3W_2Cl_9, can be readily converted to a series of [W(IV)]cluster compounds,W_3Cl_4(μ-OR)_2(OR')_2(R'OH)_2, including seven known compounds and two newcompounds with R=Me, R＇=i-Pr and sec-Bu. The crystallographic data of 7 and 8 are herebypresented.
