Unplanned downtime and polymer build-up can cost millions For a medium-sized steam cracker producing 500 kilotonnes of ethylene per year, a single day off-line can mean a loss of up to one million euros.
Evonik delivers high-performance anti-fouling and polymerization inhibitor solutions — ready-to-inject formulations of antipolymerants, antioxidants, dispersants and antifoams — that keep your processes running reliably, sustainably, and profitably.
How do polymerization inhibitors prevent fouling?
Fouling in monomer production is caused by deposits of polymeric and other insoluble material that build up in reactors, reboilers, condensers and columns and progressively limit process efficiency. The conventional responses — reducing throughput, lowering process temperatures or redesigning the plant — cut fouling at the cost of productivity or capital expenditure. Stable free radicals such as 4-Hydroxy TEMPO act as radical scavengers: they terminate the free-radical chain that starts unwanted polymerization, so the polymer never forms on the surface. Each additive is injected at the point in the system where it achieves maximum effect.
Why Choose Evonik?
- Proven Performance: Trusted additives for polymerization control and fouling prevention in the most demanding environments.
- Maximum Plant Availability: SiYPro® additives prevent in-process deposition, increase run length and throughput, improve end-product properties and reduce production costs. Preventing a single unexpected shutdown can already cover the cost of the treatment program.
- Tailored Expertise: Solutions engineered for your unique process challenges.
Solutions by Application
Polymerization Control
Prevent runaway reactions and ensure stable operations with Evonik’s advanced inhibitors:
- 4-Hydroxy TEMPO – Stable free radical that stops unwanted polymerization of vinyl monomers during production. Injected on a continuous basis into plants producing high-purity styrene monomer to avoid fouling caused by polystyrene build-up, and widely used in ethylene, butadiene, acrylics and vinyl acetate processes. Scavenges vinyl radicals even in the absence of air. →
- Acetamino-TEMPO – Antipolymerant for specialty vinyl monomers that can be separated from the monomer by distillation.
- SiYPro® A551 – High-activity radical terminator in n-butanol. In-process inhibitor and emergency shortstop for bringing runaway polymerization in storage tanks under control; mixes rapidly with the polymerizing liquid.
- SiYPro® A420 – Radical terminator formulation in water for acrylic monomer processes and monomer recovery sections that can tolerate water.
- SiYPro® S270 – Inhibitor of free-radical polymerization formulated in ethylbenzene for compatibility with hydrocarbon processes, especially styrene plants.
Anti-fouling Additives
Protect heat exchangers, reactors, and pipelines from costly fouling:
- SiYPro® antifoulants – Tailor-made formulations for the full breadth of hydrocarbon production: light-ends antifoulants, compressor and caustic tower antifoulants, emulsion breakers and corrosion inhibitors in ethylene and propylene plants; EDC light-ends and heavy-ends antifoulants in vinyl chloride production; heads column antifoulants in acrylonitrile; antifoulants for acrylic acid and ester plants; antifoulants for butadiene and isoprene extraction and purification; pyrolysis gasoline stabilizers; C4 stabilizers for butenes; and antifoulants for monomer recovery in SBR, vinyl acetate polymer and vinyl resin plants.
Evonik analyses the deposit, designs the formulation and defines the injection point for your specific system.
Process Optimization
Enhance reliability and reduce downtime with foam control solutions:
- TEGO® Antifoam WM 20 – Easily dilutable 20 % active silicone defoamer emulsion based on a special combination of siloxanes. Used for foam control in HPPO (hydrogen peroxide to propylene oxide) processes and other petrochemical processing and suited to alkaline and acidic aqueous media.
Corrosion Inhibition and Feedstock Stabilization
- SiYPro® M250 – Multifunctional corrosion inhibitor for petrochemical processing. Also used as a storage stabilizer in ETBE production and for the stabilization of raw pyrolysis oil from chemical recycling.
Your Evonik Advantage
- Operational Efficiency: Lower maintenance costs and maximize uptime.
- Product Stewardship and Documentation: Safety data sheets, registration information and handling guidance are available for every SiYPro®, TEMPO and TEGO® Antifoam grade. Hazard classification differs by grade and by solvent carrier — our specialists define dosage, injection point, storage and handling requirements with your plant team before start-up.
- Expert Support: Balanced Effective Service Technology (BEST): root cause analysis of your deposits, tailor-made antifoulant design, selection of the right injection location, on-site support during start-up and ongoing treatment optimisation. Our laboratories simulate industrial processes from acrylic acid to styrene, and our analytical service examines deposit samples taken from your plant equipment. Routine monitoring is carried out by your team using methods provided by Evonik, with our specialists available as needed.
Ready to Improve Your Process Reliability?
Discover how SiYPro® antifoulants, 4-Hydroxy TEMPO, Acetamino-TEMPO and TEGO® Antifoam WM 20 can prevent in-process deposition, increase run length and lower production costs in your plant.
Contact us today or explore our solutions to start your journey toward smarter process control.