Chemical Recycling: The Missing Piece of the Circular Plastics Puzzle

Why Mechanical Recycling Is Not Enough

The plastics industry has a math problem. Global plastic production exceeds 400 million tonnes annually, yet less than 10% is effectively recycled. Mechanical recycling — shredding, melting, and reprocessing — has been the backbone of plastics recycling for decades. But it cannot scale to meet the challenge.

Mechanical recycling suffers from fundamental limitations:

• Quality degradation: Each mechanical recycling cycle shortens polymer chains, reducing material quality. Most plastics can only be mechanically recycled 2-3 times before becoming unusable.
• Contamination sensitivity: Mixed plastics, food residue, dyes, and additives make large fractions of plastic waste unmechanically recyclable.
• Limited applicable materials: Multi-layer films, composites, and thermosets cannot be mechanically recycled at all.
• Economic marginality: Virgin plastic from cheap fossil feedstock is often cheaper than recycled material.

The result: even advanced mechanical recycling economies like the EU only mechanically recycle about 35% of collected plastic packaging. The rest is incinerated, landfilled, or exported.

This is where chemical recycling enters the picture.

What Is Chemical Recycling?

Chemical recycling breaks plastic polymers down into their molecular building blocks — monomers, oligomers, or basic hydrocarbons — that can then be rebuilt into virgin-quality plastic. Unlike mechanical recycling, chemical recycling can handle mixed, contaminated, and multi-layer plastics while producing material identical to fossil-based equivalents.

The term encompasses several distinct technologies:

Pyrolysis

The most commercially advanced approach. Plastic waste is heated to 400-700°C in the absence of oxygen, breaking long polymer chains into shorter hydrocarbon molecules. The output is pyrolysis oil that can be fed into steam crackers to produce new plastic monomers.

Status: Commercial scale. Major plants operated by Plastic Energy, Quantafuel, and others across Europe and Asia. Capacity growing rapidly.

Advantages: Can handle mixed polyolefin waste (PE, PP), well-understood process technology.

Limitations: High energy input, relatively low oil yield (60-80%), produces both fuel and feedstock outputs.

Gasification

Plastic waste is heated with controlled amounts of oxygen and steam at very high temperatures (800-1400°C), producing syngas (CO + H2). This syngas can then be converted into methanol, ethanol, or synthetic fuels via catalytic processes.

Status: Operational at scale. Companies like Enerkem and E-fuel are building commercial facilities.

Advantages: Can handle almost any carbon-containing waste (not just plastics), extremely flexible input.

Limitations: Very high capital costs, energy intensive, syngas cleanup is complex.

Depolymerization (Chemolysis)

Targets specific polymers with well-defined chemistry. Uses solvents, enzymes, or catalysts to break polymers back into their original monomers with high purity. Particularly effective for polyesters (PET) and polyamides (nylon).

Status: Growing commercial activity. Companies like Carbios (enzymatic PET), Gr3n, and IBM’s VolCat process are scaling.

Advantages: Highest quality output (virgin-grade monomers), milder conditions than pyrolysis.

Limitations: Only works for condensation polymers (PET, PU, PA), requires relatively clean input streams.

Dissolution

Uses selective solvents to dissolve specific polymers from mixed waste, separating them from contaminants and other plastics. The dissolved polymer is then precipitated in pure form.

Status: Emerging commercial. Companies like APK Technologies and PureCycle (polypropylene focus).

Advantages: Low energy, preserves polymer quality, handles complex multi-layer packaging.

Limitations: Solvent handling and recovery required, limited to specific polymer-solvent pairs.

Market Size and Investment

The chemical recycling market was valued at approximately USD 4 billion in 2025 and is projected to reach USD 11-14 billion by 2035, growing at a CAGR of 13-15%. In volume terms, the market is projected to reach 11.9 million tonnes processing capacity by 2035.

Europe leads with over 34% market share, driven by EU regulation mandating recycled content in packaging and the Single-Use Plastics Directive.

Major corporate investors include BASF, SABIC, TotalEnergies, Indorama Ventures, and ExxonMobil — all building chemical recycling capacity adjacent to their existing cracker and refinery infrastructure.

The Circular Promise vs Reality

Proponents argue that chemical recycling enables a truly circular economy for plastics — infinite recycling without quality loss. Critics counter several concerns:

Energy intensity

Pyrolysis and gasification require significant thermal energy. If this energy comes from fossil fuels, the carbon footprint advantage over virgin narrows considerably. The industry is addressing this by powering plants with renewable electricity and using the non-recoverable char as process fuel.

Yield and economics

Current pyrolysis plants achieve 60-80% oil yield from plastic waste. The remainder becomes char, gas, and losses. At current oil prices, chemical recycling is only economically viable with policy support (recycled content mandates, carbon pricing, or plastic taxes).

“Excuse for virgin production” risk

Environmental groups worry that chemical recycling provides political cover to continue virgin plastic production. If chemical recycling handles only 5-10% of plastic waste while production grows 3-4% annually, it cannot be the primary solution.

Toxic emissions

Pyrolysis of PVC-containing waste can produce dioxins and furans. Proper feedstock sorting and emission control are essential but add cost.

The Verdict

Chemical recycling is not a silver bullet, but it is an essential complement to mechanical recycling. The optimal system uses mechanical recycling for clean, single-polymer streams (PET bottles, HDPE containers) and chemical recycling for everything else — mixed films, contaminated packaging, multi-layer materials, and end-of-life composites.

The technology is proven. The economics are improving. The policy tailwinds are strong. Chemical recycling will not solve the plastic waste crisis alone, but without it, the circular economy for plastics remains impossible.

Related: Explore our glossary entries on Circular Economy, Life Cycle Assessment, and PBAT for deeper context.