Is it necessary to activate newly installed low-mercury catalysts? Activation requirements and procedures?
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In response to **environmental protection initiatives, most PVC manufacturers are now using low-mercury catalysts. Is it then necessary to carry out activation treatment with hydrogen chloride when these catalysts are newly installed? How does everyone do it? If activated, how is it used?
At present, after using low-mercury catalysts in our company, it is difficult to control the temperature; the adjustments are rather sensitive, the amount of air intake is hard to regulate, the conversion rate has decreased, and the operation is also more complicated
At present, after using low-mercury catalysts in our company, it is difficult to control the temperature; the adjustments are rather sensitive, the amount of air intake is hard to regulate, the conversion rate has decreased, and the operation is also more complicated
The newly loaded catalyst must be activated with hydrogen chloride gas, with an activation time of no less than 8 hours. It is best to activate for about 24 hours, and the activation flow rate should not be too high; an outlet hydrogen chloride purity of over 90% is considered acceptable. After introducing the mixed gas into the activated catalyst on the qualified side, it is necessary to control the temperature and flow rate, ensuring that the temperature does not exceed 120°C within 1000 hours. When a large flow rate of newly charged catalyst is used, it can easily lead to localized overheating, resulting in the sublimation of mercury chloride within the catalyst; therefore, the flow rate must be strictly controlled.
It must be activated; firstly, to ensure that the catalyst’s activity is increased as quickly as possible； The second is to ensure the service life of the converter
How does activation affect the lifespan of the converter?
How long will low-mercury catalysts be used in post-combustion? How long can it be used in total?
It mainly depends on the acetylene output specifications for converters set by your company. Under the condition that the low-mercury catalyst meets the manufacturer’s requirements, it can generally be used in the post-converter for over 3,000 hours; 8,000 hours in total is no problem either, and the maximum usage time can reach 12,000 hours. By that point, however, the catalyst loses most of its activity, with the mercury content in the waste catalyst being below 2%.