Effect of Steaming on Waste‐Derived Zeolite ZSM‐5 as Methanol‐To‐Hydrocarbons Catalyst

Abstract

The valorization of low-grade industrial residues into valuable materials has been a way to reduce the impact of the industry on planetary boundaries. Silicon-rich wastes have been used for zeolite synthesis while the impurities originating from wastes have a vital role in the physicochemical properties and the catalytic performance of waste-derived zeolites. Here, the effect of steaming and the impact of impurities on waste-derived zeolites were investigated. Steamed waste-derived zeolite ZSM-5 maintained their structure while their Brønsted acidity was decreased significantly due to dealumination. Electron paramagnetic resonance revealed that steaming of the samples resulted in the re-dispersion of Fe impurities phases. The wastederived zeolites exhibited a high amount of weak and intermediate acidity upon steaming. Interestingly, the wastederived sample with a higher amount of impurities had an increase in Lewis acidity upon steaming, while catalytic testing in the Methanol-to-Hydrocarbons reaction exhibited 10 % higher conversion and 4 % in propylene yield.[a] N. Nikolopoulos, O. van Veenhuizen, B.

Evaluating the efficacy of zeolites synthesized from natural clay for the methanol-to-hydrocarbon process

“…, clay, waste, or biomass like rice husk). 12,27–44 Zeolites are porous materials known for their large surface area, microporous structure, solid acidity, excellent thermal stability, and exceptional shape-selective catalytic capabilities. 11,45–47 The traditional zeolite synthesis protocol typically undergoes a hydrothermal crystallization method using Si sources ( e.g.…”

“…26 With this objective, efforts must be prioritized to synthesize zeolites from alternative value-added sources (e.g., clay, waste, or biomass like rice husk). 12,[27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44] Zeolites are porous materials known for their large surface area, microporous structure, solid acidity, excellent thermal stability, and exceptional shape-selective catalytic capabilities. 11,[45][46][47] The traditional zeolite synthesis protocol typically undergoes a hydrothermal crystallization method using Si sources (e.g., silica sol and tetraethyl orthosilicate (TEOS)), Al sources (e.g., aluminium isopropoxide and aluminium nitrate), and organic structure-directing agents (OSDAs).…”

“…45,[47][48][49] Using natural materials containing silicon and/or aluminum elements to synthesize zeolites directly is a green and cost-effective approach. It has been reported that various clay minerals, such as kaolin and montmorillonite, 50 natural zeolite deposits, 51 diatomaceous earth, 52 waste, 29 and biomass materials, 53 have been utilized for zeolite synthesis. Among them, the Earth's abundant kaolin (aka kaolinite, Al 4 [Si 4 O 10 ](OH) 8 ) has recently appeared as a promising source material for zeolite synthesis, 12 including zeolites X, 54 NaA, LTA, [55][56][57] MOR, 58 Y, 40,43 SAPO-34, 59,60 ZSM-5, 37,41,42,61,62 and Beta.…”