ZSM-5 for MTO
ZSM-5 is the propylene-oriented catalyst for methanol-to-olefins conversion. Its 10-MR channels (5.1-5.6 Å) lack the cage confinement of SAPO-34’s CHA framework, producing a broader product slate with a significantly higher propylene-to-ethylene ratio — the right choice when the downstream market values propylene over ethylene.
ZSM-5 vs SAPO-34 for MTO
| Performance Metric | ZSM-5 | SAPO-34 |
|---|---|---|
| C₂H₄ selectivity | 15-25% | 40-50% |
| C₃H₆ selectivity | 30-40% | 35-45% |
| C₂+C₃ total | 50-65% | 80-90% |
| Propylene/ethylene ratio | 1.5-3.0 | 0.8-1.2 |
| C₄+ byproducts | 15-30% | 5-12% |
| Single-cycle life (fixed bed) | 12-48 hours | 2-8 hours |
| Catalyst cost (relative) | Lower | Higher |
When to Choose ZSM-5 for MTO
Propylene economics: If your integrated complex consumes more propylene than ethylene — polypropylene, propylene oxide, oxo-alcohols — ZSM-5’s higher P/E ratio (1.5-3.0) reduces the need for supplementary propylene production.
Process design: ZSM-5 cokes more slowly than SAPO-34, enabling longer single-cycle operation. This is an advantage in fixed-bed or swing-reactor MTO designs where continuous regeneration is not available.
Cost: ZSM-5 is the lower-cost catalyst, both per tonne and per unit of propylene produced in propylene-maximising operation.
Recommended ZSM-5 Grades
| Objective | Recommended Grade | Key Parameters |
|---|---|---|
| Maximum propylene selectivity | Si/Al 100-300 | Suppresses hydrogen transfer and aromatisation |
| Longer catalyst life | Si/Al 200-500 | Higher SAR reduces coke formation rate |
| Balanced activity and selectivity | Si/Al 50-150 | Higher acid density for conversion, balanced with propylene selectivity |
ZSM-5’s stronger acidity drives higher conversion per active site but also promotes hydrogen transfer and aromatisation; higher Si/Al ratios (100-300) partially suppress these side reactions. Operating window: 450-550 °C, with propylene selectivity of 30-40% and P/E ratios of 1.5-3.0.
For a complete head-to-head comparison, see ZSM-5 vs SAPO-34. When requesting a sample, specify your target P/E ratio, reactor type (fluidised or fixed bed), and preferred crystal size.
Request a Sample or Quote
Share your zeolite catalyst product, application, required specification, and quantity so the right TDS, COA, sample, or quotation can be matched to your evaluation.
Request a Sample or Quote