Effect of metal loading processes on the stability and thermal transformation of Co2+- and Cu2+-zeolite Y prepared from Egyptian kaolin

This paper aims to assess the effect of the transition metals (TM) loading procedure on the incorporation of Co2+ and Cu2+ in zeolite Y, and their relevance to stability of the zeolite, particularly with respect to the thermal transformation to the spinel phases. In this work, zeolite Y prepared from Egyptian kaolin was used. XRF, XRD, TEM, UV/visible absorption measurements, and atomic absorption analyses in addition to the visual observations are recorded. XRF has been used to investigate the materials composition. TEM and XRD indicate the presence of nanoparticle spinel upon the calcination of the TM-zeolites at 1000 °C. In addition to spinel particles, XRD shows the formation of metal oxides, SiO2 and alumino-silicate phases. According to the transition metal and the cation loading process, different phases were detected. UV/visible absorption measurements and the visual observations are used to determine the experimental condition of the highest spinel content. It has been noticed that the experimental conditions of the metal sorption processes greatly affect the phase transformation. Stability and thermal transformation of zeolite depend on the initial concentration of the transition cation solutions and the number of loading cycles. - Highlights: ► We study the effects of loading procedure in the incorporation of TM in zeolite Y. ► Synthetic zeolite Y prepared from Egyptian kaolin has been used. ► The type of TM affects the stability and thermal transformation of zeolite. ► Loading processes affect the stability and thermal transformation of zeolite.