VCI28 Vanadium Corrosion Inhibitor: A High-Temperature Barrier for Refining and Turbine Systems
VCI28 captures or passivates active vanadium species that form low-melting corrosive salts at high temperature, protecting catalysts and equipment in heavy-oil processing.
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VCI28 Vanadium Corrosion Inhibitor | High-temperature vanadium corrosion | Catalyst protection | Heavy-oil processing
- High-temperature vanadium corrosion
- Active capture
- Catalyst protection
- Low dosage
- Long-cycle operation
In refining, heavy-oil processing and fluid catalytic cracking (FCC) units, an “invisible” hazard is often more difficult than ordinary corrosion. It is not acid corrosion, water corrosion or oxidation corrosion, but high-temperature corrosion caused by vanadium.
As the global share of heavy, poor-quality and residual crude processing continues to rise, the naturally occurring vanadium (V) and nickel (Ni) content in crude oil increases. Once these metal impurities enter refining units, they not only affect catalyst activity but also form highly corrosive low-melting vanadium salts at high temperature, causing sustained damage to catalysts, equipment and refractory materials.
Vanadium corrosion inhibitors have therefore become an important part of metal-contamination control in modern refining units.
01 Why Does Vanadium Become a Refinery's “Hidden Killer”?
The key is not the vanadium content itself but its chemical behavior at high temperature. Vanadium in crude oil was once regarded as a trace element with limited impact; in reality, the issue is not the content alone but its transformation and migration at high temperature.
In high-temperature processes such as FCC, delayed coking and residue hydrotreating, vanadium compounds gradually convert into active species such as vanadium oxides (for example, V₂O₅). These substances have relatively low melting points, readily form molten salts on regenerator and high-temperature equipment surfaces, and continuously react with catalyst frameworks and equipment materials.
| Damage pathway | Process | Impact on the unit |
|---|---|---|
| Destruction of zeolite structure | Vanadium reacts with the catalyst framework and damages the zeolite structure | Catalyst deactivation, reduced processing capacity and poorer product distribution |
| Accelerated high-temperature corrosion | Low-melting vanadium salts form molten deposits on metal surfaces and continue to attack them | Lower equipment efficiency and shorter maintenance intervals |
02 What Does a Vanadium Corrosion Inhibitor Actually Do?
It actively captures or passivates active vanadium species rather than simply forming a film. A common misconception is that an inhibitor works only by forming a protective film on metal surfaces. For high-temperature vanadium corrosion, this is not entirely true.
The more important role of a modern vanadium corrosion inhibitor is to actively capture or passivate active vanadium species. The basic approach is to form more stable, higher-melting compounds with active vanadium, reduce the opportunity for vanadium to react with the catalyst framework, limit molten vanadium-salt attack on equipment materials, and slow catalyst deactivation.
| Action direction | Objective |
|---|---|
| Form stable, higher-melting compounds with active vanadium | Reduce the opportunity for vanadium to react with the catalyst framework |
| Reduce molten vanadium-salt attack on equipment materials | Lower the high-temperature corrosion rate and protect metal surfaces |
| Slow catalyst activity loss | Maintain processing capacity and product distribution |
| Improve vanadium capture efficiency | Achieve effective protection at a lower dosage and reduce impact on the process |
03 What Capabilities Should an Effective Vanadium Corrosion Inhibitor Have?
| Core capability | Field significance |
|---|---|
| High-temperature stability | Vanadium corrosion mainly occurs above several hundred degrees Celsius; the inhibitor must remain active during long-term high-temperature operation |
| Vanadium capture | Rapidly forms stable compounds with active vanadium, reducing further migration and catalyst attack |
| Catalyst compatibility | Does not impair normal catalyst activity or increase side reactions, making it one of the most important industrial evaluation criteria |
| High addition efficiency | A lower dosage improves economics and reduces impact on the process |
| Long-cycle operation | Focuses not only on a single treatment but on sustained performance during continuous operation, extending stable run length |
04 Key Questions About Vanadium Corrosion
ABecause the global share of heavy-crude processing continues to rise and high-metal crude has become a trend. Vanadium contamination is no longer a problem for only a few refineries; it is an industry-wide challenge.
- Rising heavy-crude share
- High-metal crude as a trend
- Industry-wide challenge
AOrdinary oxidation corrosion mainly arises from a high-temperature oxidizing environment. Vanadium corrosion involves the formation of low-melting vanadium salts, catalyst poisoning and high-temperature molten-salt corrosion, making its damage more complex.
- Low-melting vanadium salts
- Catalyst poisoning
- High-temperature molten-salt corrosion
ANo. Overdosing increases cost and may disturb the catalyst-system balance. Industrial practice emphasizes optimized dosing based on crude-metal content, unit conditions and catalyst condition to achieve the best balance of economics and protection.
- Crude-metal content
- Unit conditions
- Catalyst condition
05 eMAI™ VCI28: A Vanadium-Corrosion Control Solution for High-Temperature Service
For heavy-oil processing and high-temperature refining, eMAI™ VCI28 is designed to control high-temperature corrosion and catalyst-deactivation risks caused by vanadium. Appropriate use of the inhibitor can help refineries reduce catalyst metal contamination, slow equipment corrosion, extend run length and improve overall unit economics and operating stability.
| Product feature | Description |
|---|---|
| Excellent thermal stability | Suitable for high-temperature refining environments and stable performance at elevated temperatures |
| Efficient vanadium control | Helps reduce the sustained impact of active vanadium on catalysts and equipment materials |
| Good system compatibility | Suitable for various refining process systems and convenient for continuous field dosing |
| Economical and efficient | Recommended dosage as low as about 100 ppm, balancing treatment performance and operating cost |
| Strong field adaptability | Suitable for FCC, heavy-oil processing, delayed coking and other industrial applications with high vanadium risk |
eMAI™ VCI28 is a high-temperature vanadium-corrosion control solution developed around this need, helping refiners respond to the challenges of high-vanadium crude while balancing equipment protection, catalyst stability and economics.
Vanadium-corrosion control depends on crude vanadium content, catalyst system, unit temperature, residence time and dosing method. Actual dosage should be established through feed analysis, catalyst evaluation and field trials rather than extrapolated from a single indicator.