Synthesis of NaX zeolite: Influence of crystallization time, temperature and batch molar ratio SiO2/Al2O3 on the particulate properties of zeolite crystals

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

“…The higher thermodynamically stable hydroxysodalite zeolite seems to be formed by the metastable NaX zeolite conversion at higher synthesis temperatures. This is in agreement with the Ostwald's law of successive transformation [37].…”

“…In both series of the experiments conducted at temperature range of 80°C-110°C, it was found that an optimum synthesis temperature of the 13X zeolite is 80°C. Increasing the zeolite synthesis temperature from 80 to 95°C leads to formation of the other zeolite types such as A and P [30,37]. At higher synthesis temperatures up to 100°C, the hydroxysodalite zeolite crystals will be formed as is shown in figure 2 (samples S 4 ) and figure 3 (samples of S 3 and S 9 ).…”

Synthesis of Pure Na–X and Na–P Zeolite from Acid-Extracting Residues of CFB Fly Ash by a Single-Step Hydrothermal Method

“…As shown by diffraction pattern in Fig. 5, the crystallinity of zeolite Na-X sample gradually increased while crystallization temperature was raised from 80 C to 100 C. The higher the temperature, the bigger the energy and the shorter the crystallization time will be 26) . At the same time, the higher temperature can enhance concentration of chemical group in sol, and it is also bene cial to crystalline.…”

On the synthesis of AlPO4-21 molecular sieve by vapor phase transport method and its phase transformation to AlPO4-15 molecular sieve

“…Also, the diffraction peaks of AlPO 4 -15 phase still increased till 180 C. This could be resulted from the higher temperature that enhance the concentration of chemical group in sol and be beneficial to crystalline. [18] With further increasing the crystallization temperature, diffraction intensities of AlPO 4 -15 got weak. Xu et al [19] pointed that the excessive crystallization Figure 4, were recorded to study the effect of crystallization temperature.…”