Closing the Loop: How Clariant is Enabling Circular Plastic

Séval: Plastic waste has become one of our most pressing environmental challenges because of the sheer volume we produce and how long it persists in the environment. Globally, we produce over 400 million tons of plastic annually, with approximately half designed for single-use purposes. When these plastics can't be recycled effectively, they end up in landfills where they can take hundreds of years to break down, or worse, they're incinerated, releasing greenhouse gases. Currently, only about 9% of all plastic ever produced has been recycled, while an estimated 8-10 million tons enter our oceans each year.

Sebastian: The real issue is that we've been operating in a linear economy – we make, use, and dispose – rather than a circular one where materials are continuously reused. Transitioning to better recycling and circular practices could significantly reduce CO2 emissions; recycling plastic saves at least 50% of carbon emissions compared to virgin production, with some studies showing savings of 70-80%. If plastics are not recycled, we need to explore for more fossil-based oil – which increases emissions; but, if we keep the plastic in the loop, we can reduce the exploration of oil and reduce the overall CO2 impact. Furthermore, while recycling is essential, the direct reduction of plastic production and consumption stands as a critical second pillar in the fight against environmental pollution, as preventing waste at the source is the most effective way to eliminate its ecological footprint.

Séval: Recycling glass and aluminum is relatively straightforward because they are elemental materials that can be melted and reformed indefinitely without losing quality. In contrast, plastics are a diverse family of polymers, each with unique chemical structures, melting points, and additives that make them difficult to process together. When different plastic types are mixed or contaminated with food residue and adhesives, the resulting material is often brittle and unusable for high-grade products. Additionally, each time you mechanically recycle plastic, it can degrade in quality, which limits how many times it can be recycled. It's like trying to unscramble an egg – once different plastics are mixed and contaminated, separating them becomes extremely challenging.

Sebastian: When mixed plastic waste exceeds the capabilities of mechanical recycling, often due to multi-layer compositions or heavy contamination, it is typically diverted into a "leakage" or "end-of-life" stream. The most common destination is waste-to-energy incineration. While this process prevents plastics from lingering in the landscape and generates usable electricity or heat, it fundamentally transforms the material into CO2 and other atmospheric emissions, effectively "linearizing" the carbon. Alternatively, these plastics end up in landfills, where their high molecular stability ensures they persist for centuries as a dormant environmental burden. From a resource perspective, this represents a significant loss of embedded energy. Plastics are essentially "solid oil," derived from fossil fuel feedstocks; when we incinerate or bury them, we discard both the physical material and the immense caloric energy used in their original synthesis. This inefficiency is the primary driver behind the development of advanced or chemical recycling, which aims at closing the loop where mechanical methods fail.

Séval: To understand the difference between these two methods, imagine mechanical recycling as shredding and reforming: you are physically breaking the plastic into flakes and melting them to create something new, but the underlying molecular chains remain the same (and grow weaker with each cycle). Chemical recycling, often called advanced recycling, is more akin to molecular deconstruction. It breaks the plastic down to its original chemical building blocks, allowing us to "reset" the material to its virgin state.

The most common method used is pyrolysis, a process that subjects mixed plastic waste to high heat in the absence of oxygen. This breaks the polymers down into a liquid known as pyrolysis oil (or "pyoil"). This oil serves as a secondary feedstock that can be purified and re-introduced at the very beginning of the plastic production chain. The primary advantage here is twofold: first, it can process complex, contaminated, or multi-layered plastics that mechanical systems reject; and second, the resulting plastic is chemically identical to "new" fossil-based plastic. This allows for infinite loops without the loss of quality typically seen in traditional recycling.

Sebastian: Historically, true circularity has been hindered by two primary technical barriers. First is the "chemical cocktail" inherent in mixed plastic waste; this volatile mix of polymers and contaminants - such as chlorine and nitrogen - varies with every batch, often jeopardizing equipment integrity and product quality. Maintaining a stable output from such unpredictable feedstock remains a significant engineering challenge.

Sebastian: Think of Clarit Pyrolyze as the "intelligence" inside the pyrolysis oven. While many processes still rely on raw, blunt heat to melt and break down plastic, Clarit Pyrolyze works at a molecular level to ensure the resulting oil is high-quality and contains fewer impurities from the start. This makes the process overall more economic and sustainable.

Clarit Protect Adsorbents then steps in as the essential secondary purification phase. It’s a specialized adsorbent series designed to strip away another bulk of the contaminants, ensuring the oil is stable and clean enough for safe transport. For plant operators, this is a major strategic win: it provides a low-CAPEX way to hit strict purity standards while acting as a vital buffer to smooth out the inevitable fluctuations in waste quality. For the industry this allows to have smaller, decentralized plastic pyrolysis plants, close to where the waste accumulates.

Séval: This is one of the key innovations that make our technology commercially viable. Some alternative technologies need three to four separate reactors to achieve the same level of purification that our HDMax™ catalysts deliver in a single step.

Think about what that means practically: fewer reactors mean significantly lower capital investment – you're building less equipment. It means reduced operational complexity – less equipment to monitor and maintain. It means lower energy consumption – you're not heating and cooling materials multiple times. And it means a smaller physical footprint for the facility.

Additionally, our technology enables subsequent hydrocracking to produce naphtha-like hydrocarbon fractions, giving producers even more flexibility in their product output. This efficiency is crucial for making chemical recycling economically competitive with virgin plastic production, which is essential for widespread adoption.