Conversion of Methanol to Olefins over Modified OSDA-Free CHA Zeolite Catalyst

Abstract

Methanol to olefins (MTO) is an essential process that produces olefins from both renewable and fossil fuels resources. Chabazite (CHA) is an efficient catalyst for MTO process due to its distinct properties that promote light olefins (i.e., ethylene and propylene) production. Herein, we report a series of chabazite-based catalysts (OSDA-free with enhanced textural properties) that facilitate the MTO reaction. The synthesized CHA was modified by steam injection (CHA-S), acid treatment (CHA-A), steam and acid treatment (CHA-SA), and metal incorporation (CHA-SA (Mg), CHA-SA (Ca), and CHA-SA (Ba)). The catalysts were characterized by several characterization techniques. The structure was investigated using X-ray diffraction (XRD) and nuclear magnetic resonance, while the morphology and physical properties were studied by field emission scanning electron microscopy (FE-SEM), N2 adsorption/desorption, and ammonia temperature-programmed desorption (NH3-TPD). The catalysts were evaluated at 450 °C until deactivation. CHA modified by only acid treatment showed higher selectivity to olefins from ca. 92 to 95 wt.% but suffered quick deactivation. CHA modified with both steam and then acid treatment was more stable in the MTO process.

A Review on SAPO‐34 Zeolite Materials for CO2 Capture and Conversion

“…SAPO‐34 materials have received considerable scientific attention because of their high activity toward light olefins [55,74] . SAPO‐34 has been applied in catalytic processes, such as MTO [75–85] . Related research works [86,87] have shown that synthesizing a hierarchical structure that reduces the crystal size of the material regulates the crystal acidity, which can improve the catalytic activity of SAPO‐34, especially for MTO reactions.…”

“…[55,74] SAPO-34 has been applied in catalytic processes, such as MTO. [75][76][77][78][79][80][81][82][83][84][85] Related research works [86,87] have shown that synthesizing a hierarchical structure that reduces the crystal size of the material regulates the crystal acidity, which can improve the catalytic activity of SAPO-34, especially for MTO reactions.…”

Recent Progress of SAPO-34 Zeolite Membranes for CO2 Separation: A Review

“…In addition to distinct pore size and volume, SAPO-34 material exhibits moderate to high hydrophobicity and has high thermal and hydrothermal stability. Due to these characteristic features, SAPO-34 has been extensively used in the methanol to olefin (MTO) process [ 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 ]. In recent years, SAPO-34 has been investigated for CO 2 remediation, including CO 2 capture [ 49 , 50 , 51 ], conversion [ 52 , 53 , 54 ], and separation [ 49 ].…”

Technoeconomic Feasibility of Hydrogen Production from Waste Tires with the Control of CO2 Emissions

“…Generally, it has been observed that the increase in the temperature attributes to more gas yield with higher hydrogen contents with the suppression of tar and char concentrations. The obtained syngas could be used to produce several fuels and chemicals. , …”

“…The obtained syngas could be used to produce several fuels and chemicals. 33,34 Air and steam are the two most commonly used gasification agents, and several studies have been conducted on the gasification of scrap tires utilizing these gasification agents to analyze their impact on the final product and the overall process. Xiao et al 35 studied the impact of equivalence ratio (ER) on the gas yield using air as a gasification agent.…”