The mineral of manganese oxalate dihydrate was synthesized in aqueous and organic-water binary solvent system (OWBS), respectively. The samples were characterized by XRD and SEM. The results show that OWBS can effectively control the phase and morphology of manganese oxalate dihydrate. The distinction of thermal decompositon of monoclinic and orthogonal manganese oxalate dihydrate can be ascribed to the different linkage mode of manganese cation, oxalate anion and crystallized water in inter-molecules. The kinetic parameters of thermal decomposition were obtained by TG-DTA curves in various scan rates, and notably, porous manganese oxide was prepared from orthogonal manganese oxalate.
