On the formation of CoAPSO-44

Abstract Hydrothermal synthesis of CoAPSO-44 in the presence of cyclohexylamine (CHA) as the template is generally accompanied by the formation of an unknown phase, “Co(APSO)N.” Electronic spectroscopy indicates that CO(APSO)N contains Co2+ in a pentacoordinated environment. When Co(APSO)N is heated at 195°C in a water suspension under autogenic pressure, two processes occur: (a) a partial conversion of Co(APSO)N into CoAPSO-44 and (b) decomposition of Co(APSO)N into Co- and Al-phosphates. Thermal removal of CHA from Co(APSO)N results in a breakdown of the latter's cyrstal lattice.