| Abstract: The pink powder of manganese L-threonate was obtained by extracting with alcohol the concentrated solution derived from the reaction between L-threonic acid solution prepared by double decomposition reaction of calcium L-threonate with oxalic acid and superfluous manganese oxide at 80℃ for certain time. The composition of the new compound was determined by chemical and elemental analyses and its formula fits Mn(C4H7O5)2·H2O, the IR spectra indicated that Mn2+ in the compound coordinates to oxygen atom of the carboxyl group, while the proton of the carboxyl group is dissociated, it was assumed that the coordination number of Mn2+ was 4. The results of TG-DTG showed that the compound have fairish stability, the intermediate and final product of the thermal de-composition of the compound are Mn(C4H7O5)2 and MnO2, respectively. The constant volume combustion energy of the compound, ΔcE, were determined by a precise rotating-bomb calorimeter at 298.15K, it was (-3384.30±1.21)kJ·mol-1, its standard enthalpy of Combustion,ΔcHm?,and standard enthalpy of formation,ΔfHm? , were calculated. They are (-3383.07±1.21)kJ·mol-1 and (-2 571.68±1.63)kJ·mol-1, respectively. |
