Chemical recycling holds the key to keeping plastics in the loop. Plastic waste is chemically converted into substances that can be reused as raw materials for plastic production. Pyrolysis oil is an intermediate product during this process. Among the main contaminants in pyrolysis oil are nitrogen, sulfur, and halogens. These components can cause fouling, corrosion, and catalyst poisoning during further processing. Therefore, quality control of the pyrolysis oil is essential to optimize its treatment and prevent emissions, extended maintenance cycles, and low-quality hydrocarbon products.