The Davy VCM flow sheet employs a special PRICAT mercury-free catalyst (MFC) formulation, the advantages of which are outlined below:
Traditionally, VCM production from acetylene has accounted for the largest intentional use of mercury in the world.
Johnson Matthey’s PRICAT MFC has the potential to transform the acetylene-to-VCM industry by completely eliminating the use of mercury from the process.
PRICAT MFC is guaranteed non-toxic and not harmful for the environment as it does not contain any volatile components that can be released to atmosphere or contaminate ground water.
Additional advantages of PRICAT MFC include:
- No risk of mercury poisoning to VCM plant personnel.
- PRICAT MFC has a much longer lifetime than mercury catalysts.
- In existing plants, it can also be loaded directly into both primary and secondary reactors, whereas mercury catalysts typically require shifting from one reaction stage to the next.
- Consequently, PRICAT MFC delivers significantly reduced catalyst loading and unloading per year, saving downtime, maintenance and plant staffing costs.
- Less process equipment required due to the absence of any steps for mercury capture and handling, and treatment of mercury-contaminated waste water.
- PRICAT MFC’s high selectivity towards VCM ensures efficient use of the HCl and acetylene reactants.
- The low by-product formation that results means that little separation is required to produce high-purity VCM.
- Fewer reactors are required due to the high reaction yield delivered by PRICAT MFC.
JM Davy’s VCM process technologies have been designed to maximise the benefits of PRICAT MFC and reduce catalyst costs by the following means:
The Davy flowsheet achieves a higher VCM yield from PRICAT MFC (kg VCM/kg catalyst) than other VCM processes using the same catalyst.
- When used in the Davy VCM flow sheet, PRICAT MFC achieves a significantly higher VCM productivity (kg VCM/kg catalyst/hour).
- This means Davy VCM can use fewer reactors and less catalyst than other VCM processes using PRICAT.