ZSM-5 Zeolite Catalyst

ZSM-5 is the most widely used shape-selective zeolite catalyst in industrial chemistry. Its MFI framework with 10-membered ring channels (5.1-5.6 Å) provides molecular sieving that excludes molecules too large to enter the pore system, while strong Brønsted acidity drives reactions inside the channels. This combination of size exclusion and acid catalysis is what makes ZSM-5 indispensable across refining, petrochemical, and environmental applications.

We supply ZSM-5 in H-form (acidic, ready to use), NH₄-form (calcines to H-form on-site), and Na-form, with Si/Al molar ratios from 20 to over 3000. Every shipment includes a Certificate of Analysis with batch-specific XRD, BET, and chemical composition data.

How to Select the Right ZSM-5 Grade

The three decisions that determine which ZSM-5 grade fits your process:

Si/Al ratio controls acidity and hydrophobicity. Lower ratios (20-50) provide higher acid site density for cracking and alkylation. Higher ratios (300-3000) create a more hydrophobic framework suited for VOC adsorption and reactions in aqueous or humid environments.

Particle size affects diffusion and catalyst lifetime. Nano-scale ZSM-5 (0.1-0.5 μm) reduces diffusion path length for faster reactions and slower coking. Micron-grade powders (1-5 μm) work well in fluidized beds and extruded forms. Specify your target range when requesting a sample.

Ionic form determines the active site type. H-form (proton-exchanged) is the standard acidic form for most catalytic applications. NH₄-form is a precursor that converts to H-form during calcination at 500-550 °C. Na-form is non-acidic and used as a precursor for ion exchange.

Available ZSM-5 Grades

We supply ZSM-5 in the following standard grades. Custom formulations available on request.

All grades are available with Certificate of Analysis. If your target Si/Al ratio, particle size, or form is not listed, request a custom specification.

Key Specifications

Available forms: powder (0.1-5 μm), extrudates (1.5-3 mm diameter), and custom shaped bodies. Tell us your reactor configuration and we will recommend the right form factor.

FCC Additives — Propylene and Octane Enhancement

ZSM-5 is the dominant FCC additive worldwide because it selectively cracks low-octane gasoline-range olefins into lighter olefins — primarily propylene — while the Y-zeolite-based base catalyst handles primary cracking. Adding 2-10 wt% ZSM-5 to an FCC catalyst inventory typically increases propylene yield by 2-6 percentage points and raises gasoline research octane by 1-3 numbers.

Key mechanism: ZSM-5’s 10-MR channels crack C₇-C₁₂ linear olefins to C₃-C₅ olefins. Branched and cyclic molecules cannot enter the pores, so high-octane gasoline components are preserved. For refineries targeting maximum propylene, higher ZSM-5 loadings and lower Si/Al ratios (20-50) are recommended.

See ZSM-5 for FCC Additives for detailed operating conditions and yield data.

MTO and MTP — Methanol to Light Olefins

In methanol-to-olefins and methanol-to-propylene processes, ZSM-5 provides a higher propylene-to-ethylene ratio compared to SAPO-34. This makes it the preferred catalyst when propylene is the target product rather than ethylene. ZSM-5 also offers better hydrothermal stability under the steam-rich MTO reaction environment, though it produces more C₄+ byproducts than SAPO-34.

Typical operating window: 400-500 °C, WHSV 1-4 h⁻¹, atmospheric pressure. Si/Al ratios of 50-200 provide the best balance of activity and selectivity. For MTP specifically, ZSM-5 is essentially the only commercial catalyst, delivering propylene selectivities of 40-50%.

See MTO/MTP for application-specific catalyst selection guidance.

VOC Removal — Hydrophobic Adsorption

High-silica ZSM-5 (Si/Al >300) is an effective adsorbent for volatile organic compounds in air and gas streams. Its hydrophobic framework preferentially adsorbs non-polar VOCs (benzene, toluene, xylene, chlorinated solvents) over water vapor, making it suitable for humid exhaust streams where activated carbon would saturate.

Regeneration is by thermal desorption at 200-350 °C in air or inert gas. Particle size and bed configuration depend on flow rate and pressure drop constraints. See VOC Removal for application details.

Alkylation — Shape-Selective Solid Acid

ZSM-5 catalyzes aromatic alkylation reactions with shape selectivity derived from its medium-pore channels. In ethylbenzene production and xylene isomerization, ZSM-5’s pore constraints favor the para-isomer over bulkier ortho- and meta-isomers. This para-selectivity is a key advantage over large-pore zeolites like Y and Beta, which produce equilibrium isomer distributions.

See Alkylation for solid acid catalyst options across zeolite types.

Technical Documentation

Every ZSM-5 shipment includes a batch-specific Certificate of Analysis with XRD pattern, BET surface area, SiO₂/Al₂O₃ ratio, Na₂O content, and particle size distribution. Download the ZSM-5 Technical Data Sheet for detailed specification ranges and typical batch data.

Compare ZSM-5 against other catalyst options:

• ZSM-5 vs Beta — MFI vs BEA for FCC, alkylation, and hydrocracking
• ZSM-5 vs SAPO-34 — MTO catalyst selection: propylene vs ethylene
• ZSM-5 vs Y Zeolite — Medium-pore vs large-pore for FCC systems