Preparation of 13X zeolite powder and membrane: investigation of synthesis parameters impacts using experimental design

Abstract

The Plackett—Burman method was used to identify and rank most affective parameters on hydrothermal synthesis and properties of the 13X zeolite powder with gel composition of Al _2 O _3 :aSiO _2 :bNa _2 O:cH _2 O. The affective parameters of SiO _2 /Al _2 O _3 ratio, synthesis mixture alkalinity, synthesis temperature, and water content were selected for further study of their impacts and gel composition optimization using the Taguchi method. The synthesized powders were characterized by XRD and SEM analysis. Synthesis temperature and mixture alkalinity were found as the most affecting parameters on the 13X zeolite synthesis at the best gel composition of Al _2 O _3 :5.4SiO _2 : 13Na _2 O: 840H _2 O. Then 13X zeolite membranes were synthesized on the seeded supports using the optimum gel composition and impacts of synthesis temperature and time and coating layer number on their H _2 and CO _2 permeances and ideal H _2 /CO _2 selectivity were studied. The optimum 13X zeolite membrane for H _2 /CO _2 separation was obtained by three layer coatings at 80 °C for 16 h with H _2 permeance of 2.88 cm ^3 cm ^−2 .Pa.s and ideal H _2 /CO _2 selectivity of 4.72.

Keywords

• 13X zeolite powder
• gel composition
• zeolite membrane
• hydrothermal synthesis
• gas permeation