화학공학소재연구정보센터
Chemical Engineering Journal, Vol.369, 996-1004, 2019
In situ investigations on the amorphous to crystalline phase transformation of precursors for methanol synthesis catalysts
Two in situ methods are presented to study phase transformations in the synthesis of Cu/Zn hydroxycarbonates as catalyst precursors for industrial methanol production. In contrast to the well-established application of in situ FTIR probes in the detection of liquid phase concentrations, we evaluated spectra arising from the structural changes in the solid phase during the transformation of amorphous georgeite to nanocrystalline zincian malachite. Further, a novel microreaction system is employed to gain statistical insight on the scattering of the reaction time as a function of various process parameters. The obtained transformation kinetics during aging are described by a model based on the theory of solvent-mediated phase transformations showing excellent agreement with experimental results. The quantitative impact of temperature, concentration and zinc content on dissolution, nucleation and growth of the respective phases is discussed.