STUDY ON THE ELECTROCHEMICAL BEHAVIOR OF ION EXCHANGE MEMBRANE IN PREPARING POTASSIUM CARBONATE

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.

Mourning a Master Ji Xianlin, China’s foremost expert in cultural study and exchange, dies at 98

Always plainly dressed and amiable, Ji Xianlin wouldn’t be given a second glance in a crowd. Yet looks can be deceiving. He was

A study of ion exchange selectivity coefficient by cyclic voltammetric measurement

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.

Kinetic study on the ligand exchange reactions between bis(alkylxanthato)palladium(II)and bis(N,N-dialkyldithiocarbamato)palladium(II)by high-performance liquid chromatography

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.

Studies on the alcohol exchange reactions of methoxide ditungsten [W(IV)] compound W_2Cl_4(OCH_3)_4(CH_3OH)_2, prepared from (n-Bu_4N)_3W_2Cl_9

(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.