Effect of Steaming on Waste‐Derived Zeolite ZSM‐5 as Methanol‐To‐Hydrocarbons Catalyst
Nikolaos Nikolopoulos, Oscar van Veenhuizen, Bert M. Weckhuysen
Abstract
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 waste‐derived zeolites exhibited a high amount of weak and intermediate acidity upon steaming. Interestingly, the waste‐derived 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.