Ethylene Purification Adsorbent

What Is an Ethylene Purification Adsorbent?

An ethylene purification adsorbent is a CuO-ZnO adsorbent specifically developed for the removal of CO from polymer-grade ethylene feedstock. It also effectively removes trace amounts of O₂, H₂S, COS, AsH₃, PH₃, and other impurities that can poison downstream polymerization catalysts. These trace contaminants cause catalyst deactivation and disrupt normal polyethylene production. The adsorbent is prepared by a co-precipitation method, ensuring uniform dispersion of active components (CuO-ZnO) for high selectivity and activity. It features high mechanical strength, large adsorption capacity, excellent performance, and convenient operation, making it ideal for ethylene purification in polyethylene production units.

Key Takeaways

• Purpose: Removes CO plus trace O₂, H₂S, COS, AsH₃, and PH₃ from polymer-grade ethylene in a single guard bed.
• Mechanism: CuO-ZnO active components made by co-precipitation, working through catalytic oxidation and chemisorption.
• Why it matters: Protects Ziegler-Natta and metallocene polymerization catalysts from irreversible poisoning.
• Where it fits: Final trace-impurity guard bed in the ethylene purification train, typically downstream of drying and desulfurization stages such as COS Adsorbent and CD Adsorbent.

Composition & Structure

Active Components:

• CuO (Copper Oxide) — Primary active component for CO removal through catalytic oxidation and chemisorption
• ZnO (Zinc Oxide) — Co-active component enhancing selectivity and providing support for copper oxide dispersion

Physical Form: The adsorbent is manufactured using a co-precipitation process followed by pelleting, producing uniform black cylindrical pellets (Φ5×5 mm, with Φ5×3 mm also available). This cylindrical shape ensures good flow distribution, low pressure drop, and excellent mechanical strength (radial crush strength ≥ 80 N/cm) for industrial service.

Purification Mechanism

The adsorbent removes contaminants through catalytic and chemisorption mechanisms:

1. CO Removal:

• CO is oxidized to CO₂ on the CuO-ZnO active surface
• In the presence of trace O₂, CO + ½O₂ → CO₂ (catalytic oxidation)
• Even at ambient temperature, the CuO-ZnO system exhibits high CO conversion efficiency

2. Multi-Contaminant Capture:

• O₂ is removed through catalytic reduction or direct chemisorption on Cu sites
• H₂S and COS are captured by CuO through sulfidation: CuO + H₂S → CuS + H₂O
• AsH₃ and PH₃ are irreversibly chemisorbed on the active metal surface

This multi-mechanism approach enables comprehensive purification of ethylene streams in a single guard bed.

Key Advantages

Co-Precipitation Technology:

• Uniform dispersion of CuO and ZnO active components ensures consistent performance
• High surface area and intimate contact between active phases provide superior activity

High Selectivity & Activity:

• Specifically targets CO without excessive reaction with ethylene
• High activity at ambient to moderate temperatures reduces energy consumption

Robust Mechanical Properties:

• Radial crush strength ≥ 80 N/cm withstands high-pressure operation and thermal cycling
• Low attrition rate minimizes fines generation and pressure drop increase

Large Capacity:

• High adsorption capacity extends service life
• Reduces replacement frequency and operating costs

Simple Operation:

• No complex pre-treatment or activation required
• Easy loading and straightforward operation in existing guard bed vessels

Reference Operating Conditions

Process Conditions:

• Temperature: Ambient–150°C
• Pressure: Atmospheric–6.0 MPa
• Liquid Space Velocity: 0.5–6 h⁻¹

Feed Specifications:

• Polymer-grade ethylene streams
• Also applicable to other olefin streams requiring CO and trace contaminant removal

Performance Output:

• CO removal to below detectable limits
• Trace O₂, H₂S, COS, AsH₃, PH₃ removal to ppb levels

Applications in Polyethylene Production

PE Polymerization Feed Guard (Primary Application): Polymerization catalysts used in polyethylene production — including Ziegler-Natta and metallocene catalysts — are extremely sensitive to trace contaminants. CO, O₂, H₂S, COS, AsH₃, and PH₃ can all cause irreversible catalyst deactivation, leading to reduced polymer yield, off-spec product, and unplanned shutdowns. The ethylene purification adsorbent serves as the critical guard bed upstream of the polymerization reactor, delivering product-spec purity ethylene. It is typically installed as the final stage of a purification train, following upstream desulfurization and dehydration steps such as those handled by COS Adsorbent and CD Adsorbent. For the propylene equivalent of this same guard bed role, see our Propylene Purification Adsorbent.

Cracked Gas Purification: In steam cracking units, the ethylene product stream contains trace amounts of CO from the cracking process. This CO must be removed to very low levels before the ethylene can be used as polymerization feedstock.

Refinery Ethylene Streams: Ethylene-containing streams from catalytic cracking units (ERU — Ethylene Recovery Units) and other refinery processes may contain CO, sulfur compounds, and other contaminants. The adsorbent purifies these streams to meet polymerization-grade specifications.

Styrene Production Feed: Ethylene used in styrene production processes also requires deep purification to protect downstream catalysts and ensure product quality.

Service Life

The adsorbent operates primarily on a sacrificial (chemisorption) mechanism. Service life depends on:

• Inlet contaminant concentrations (CO, O₂, H₂S, COS, AsH₃, PH₃)
• Operating temperature and pressure
• Space velocity and feed flow rate
• Required outlet purity specification

The adsorbent is replaced once its capacity is exhausted, with the replacement interval determined by actual operating conditions. For guidance on expected service life under your specific feed composition, contact our technical team — see our companion guide, What Is an Ethylene Purification Adsorbent? for a deeper look at selection and operating considerations.

Why Choose Our Ethylene Purification Adsorbent?

1. CO-Focused Purification

Specifically designed for CO removal from polymer-grade ethylene, with proven performance in PE production.

2. Multi-Contaminant Removal

Simultaneously removes CO, O₂, H₂S, COS, AsH₃, and PH₃ in a single guard bed.

3. Co-Precipitation Technology

Uniform active component dispersion ensures high selectivity, activity, and consistent batch-to-batch quality.

4. High Mechanical Strength

Radial crush strength ≥ 80 N/cm for reliable operation under high pressure.

5. Wide Operating Window

Ambient to 150°C and atmospheric to 6.0 MPa, compatible with diverse process configurations.

6. Large Capacity & Long Service Life

High adsorption capacity reduces replacement frequency and operating costs.

7. Customizable Supply

Size (Φ5×5 mm or Φ5×3 mm) and formulation can be adjusted to match specific process requirements. Contact our technical team for tailored solutions.

Packaging & Shipping

• Packaging: Sealed steel drums (25 kg or 40 kg net weight) with inner double-layer plastic bags to prevent moisture absorption and contamination during transport.
• MOQ: 1 ton
• Container Loading: Standard 20' or 40' containers (FCL); LCL available for smaller orders
• Ports: Flexible — shipped from major Chinese ports based on buyer location and shipping line availability
• Lead Time: Contact our team for current lead times based on order volume

Documents & Certificates

• Certificate of Analysis (COA)
• Safety Data Sheet (SDS/MSDS)
• Certificate of Origin
• Packing List & Commercial Invoice

Storage & Handling

Storage: Store in a cool, dry, well-ventilated area. Protect from moisture, chemical contamination, and physical impact. Keep sealed until loading. Shelf life exceeds 3 years when stored properly in original unopened packaging.

Handling: Use appropriate personal protective equipment (PPE) when handling. Avoid inhalation of dust and contact with skin or eyes. Sieve before loading to remove fines.

FAQ

Q1: What contaminants does this adsorbent remove?

It primarily removes CO from polymer-grade ethylene feedstock, while also removing trace amounts of O₂, H₂S, COS, AsH₃, PH₃, and other impurities that can poison polymerization catalysts.

Q2: What is the active composition?

The active components are CuO (copper oxide) and ZnO (zinc oxide), prepared by co-precipitation method for uniform dispersion and high activity.

Q3: What are the operating conditions?

Temperature: Ambient–150°C. Pressure: Atmospheric–6.0 MPa. Liquid space velocity: 0.5–6 h⁻¹.

Q4: What particle sizes are available?

Standard size is Φ5×5 mm cylindrical pellets. Φ5×3 mm is also available. Custom sizes can be provided upon request.

Q5: Why is CO removal critical for polyethylene production?

Trace CO in ethylene feedstock poisons Ziegler-Natta and metallocene polymerization catalysts, causing reduced catalyst activity, lower polymer yield, and off-spec product. Removing CO to below detectable limits is essential for stable PE production.

Q6: What is the mechanical strength of the adsorbent?

The radial crush strength is ≥ 80 N/cm, providing excellent mechanical integrity for high-pressure industrial service.

Q7: How does this fit into a full ethylene purification train?

It is typically the final guard bed stage, installed downstream of desulfurization and dehydration steps to deliver polymerization-grade purity ethylene.

Closing CTA

Ready to secure a reliable bulk supply of Ethylene Purification Adsorbent for your Middle East operations? Contact Sorbsieve's technical team today for a customized quote and technical data sheet.

Need a Custom Solution?

For bulk pricing and grade recommendation, please send your feed composition and required CO/trace contaminant outlet specifications to us. Our technical team will get back to you within 24 hours with a tailored solution.

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