Polypropylene: Production route
Loop or gas phase: how licensors compete
What this tab covers How it is made: the main production routes or, for product families, the main product types and technologies, compared on share of supply, inputs per tonne, plant scale, yield, co-products and unit cost.All PP is made from propylene with supported titanium Ziegler-Natta catalysts (metallocene PP is a niche). Licensed processes differ in reactor type: liquid-pool loop reactors (Spheripol), gas-phase reactors (Unipol PP, Novolen, Innovene PP), and hybrids (Spherizone, Borstar PP). Each makes three product families: homopolymer (stiff), random copolymer (clear) and impact or block copolymer (tough). The real competitive split is upstream: whether propylene comes from a cracker, a refinery FCC or a PDH unit.
Routes compared
| Route | Share of supply | Inputs per tonne | Typical scale | Yield | Co-products | Unit cost |
|---|---|---|---|---|---|---|
| Bulk loop process (e.g. LyondellBasell Spheripol) | about 40-45% of global PP capacity (indicative) | about 1.0-1.01 t propylene, about 0.3-0.4 MWh power and some steam (indicative) | 300-550 kt/yr per line (indicative) | about 99% (indicative) | atactic PP and oligomers in small amounts | propylene cost plus about $80-150/t conversion (indicative) |
| Gas-phase processes (Unipol PP, Novolen, Innovene PP) | about 35-40% (indicative) | about 1.0 t propylene; about 0.3-0.4 MWh per t (indicative) | 300-600 kt/yr (indicative) | about 99% (indicative) | minor | similar to loop; lower capex for some designs (indicative) |
| Integrated PDH-PP | about 15-20% of propylene supply, with about half of 2024-2028 propylene additions (propylene tile) | about 1.2 t propane per t PP via propylene (propylene tile) | 500-900 kt/yr PP (indicative) | about 85% selectivity in PDH (propylene tile) | about 0.04 t hydrogen per t propylene (propylene tile) | propane cost plus about $250-400/t combined PDH and PP conversion (indicative) |
| Circular and bio-attributed PP | a few% at most (indicative) | varies | mass-balance volumes of tens of kt per producer (indicative) | as fossil for mass balance; about 70-90% for mechanical recycling (indicative) | rejects and residues in recycling | certified circular PP carries a premium; not published |
How each route works
Bulk loop process (e.g. LyondellBasell Spheripol)Propylene is polymerised as a liquid in loop reactors, followed by a gas-phase reactor for impact copolymers. The most licensed PP process worldwide.
Proven, flexible across homopolymer, random and impact grades; strong licensor support.
indicative (industry standard) Gas-phase processes (Unipol PP, Novolen, Innovene PP)Propylene is polymerised in fluidised-bed or stirred-bed gas reactors; two reactors in series make impact copolymers with high rubber content.
Good for high-impact automotive copolymers; slightly narrower homopolymer range.
indicative Integrated PDH-PPA propane dehydrogenation unit feeds an on-site PP plant, so PP economics depend on the PP-propane spread. China built most of the world's PDH-PP since 2015.
Single product and quick to build, but exposed to imported propane and to China's 2025 tariff swings on US propane.
propylene tile; indicative Circular and bio-attributed PPPyrolysis oil from plastic waste or bio-naphtha from used cooking oil is fed to a cracker and allocated to PP by ISCC Plus mass balance; mechanically recycled PP is re-extruded directly.
Lets brands claim recycled or bio content; mass-balance claims are contested.
propylene tile (Neste, Borealis, LyondellBasell); indicative Unit economics are indicative ranges from the sources named; costs move with feedstock and energy prices, plant size and region.