Direct synthesis of ZSM-5 from kaolin and the influence of organic template

Abstract

We investigated the transformation of kaolin to ZSM-5 using hydrothermal synthesis method and the influence of organic template as a structure-directing agent. The formation of ZSM-5 from kaolin occurred via dissolution of kaolin to form amorphous silica. Zeolite-like analcime produced when the hydrothermal treatment was extended to 18 h. We found synergistic effect of using a mixture of TPAOH and TPABr organic template to enhance kaolin dissolution, initiate ZSM-5 formation and inhibit the transformation of ZSM-5 to analcime.

Green and low-cost synthesis of zeolites from kaolin: a promising technology or a delusion?

“…58 Prasetyoko et al have obtained ZSM-5 with 100% relative crystallinity without pretreatment from kaolin containing 8.89 wt% Fe 2 O 3 and many other impurities. 99 Quartz and iron ions are undesirable when zeolites are used as detergents. 3 Kwakye-Awuah et al have shown that zeolite NaY obtained from Anfoega kaolin has lower relative crystallinity than NaY obtained from Awaso Volta kaolin under the same experimental conditions.…”

“…58 Prasetyoko et al have obtained ZSM-5 with 100% relative crystallinity without pretreatment from kaolin containing 8.89 wt% Fe 2 O 3 and many other impurities. 99 Quartz and iron ions are undesirable when zeolites are used as detergents. 3…”

“…116 The transformation occurs faster with increasing temperature and NaOH concentration, which is also confirmed in other studies. 82,[220][221][222][223][224][225] ZSM-5 is replaced by quartz, ANA, MOR 94,97,99 and GIS. 43 Hartanto et al have observed that the type of seed in the synthesis of ZSM-5 affects the phase purity of the product.…”

The impregnation of ZnO onto ZSM-5 derived from red mud for photocatalytic degradation of methylene blue

“…ZSM-5 was synthesized from RM using the dualhydrothermal method [26] as follows. RM was pretreated by an alkaline fusion reaction at 450 °C for 2 h before adding distilled water and stirring for 24 h. The filtrate was separated and dried at 105 °C for 24 h. At molar compositions of 0.2 silicon dioxide (SiO 2 ): 0.004 dialuminium trioxide: 0.04 tetrapropylammonium: 3.6 water, the resulting solid substance was used to prepare ZSM-5 by dissolving it in distilled water.…”