Catalyst to Remove Acetylene from Ethylene Streams for Polyethylene Synthesis

Purifies Ethylene Gas Without Hydrogenation by Removing Acetylene through Polymerization

This catalyst selectively polymerizes the acetylene contained in ethylene gas, purifying streams more easily for the production of polyethylene. Analysts project the global polyethylene market to exceed $140 billion in value by 2026. Synthesizing polyethylene gas for its many industrial applications requires ethylene gas significantly free of acetylene, which most manufacturers remove by hydrogenating it into ethylene. This step requires excess ethylene and a catalyst to avoid hydrogenating the ethylene into ethane, but available catalysts have limited stability and selectivity.

Researchers at the University of Florida have developed a catalyst that polymerizes the acetylene in ethylene gas streams into solid cyclic polyacetylene without reacting with the ethylene. Removing acetylene via selective catalysis rather than hydrogenation enables more efficient purification and processing of ethylene gas streams in the production of polyethylene.

Application

Catalytic removal of acetylene from ethylene gas for more efficient polyethylene manufacturing

Advantages

• Purifies ethylene streams without hydrogenation, reducing cost of synthesizing industrial polyethylene gas
• Directly removes acetylene from ethylene in a continuous process, increasing efficiency
• Produces cyclic polyacetylene, an isolable side product with potential use as an additive

Technology

Ethylene gas bubbles through a solution of this catalyst, polymerizing the acetylene without reacting with the ethylene. The catalytic solution converts acetylene into insoluble cyclic polyacetylene, which readily separates from the stream to purify ethylene gas for polyethylene production. Direct catalytic removal of acetylene replaces the standard hydrogenation reaction to facilitate more efficient processing and reduce energy required in polyethylene synthesis.