How to prevent and solve material poisoning caused by platinum catalysts
Raw material purification:
Before the raw materials are introduced into the reaction system containing platinum catalysts, use adsorption, distillation, washing and other methods to remove impurities that may cause poisoning. For example, when natural gas is used as raw material for reforming reaction to produce synthesis gas, the content of sulfur-containing and nitrogen-containing compounds is reduced to an extremely low level through pretreatment processes such as desulfurization and denitrification to ensure that the platinum catalyst is not poisoned.
Reaction condition optimization:
Reasonably control the reaction temperature, pressure, reactant concentration and other conditions to avoid excessive generation of intermediate products such as carbon deposition that are harmful to the catalyst during the reaction. At the same time, by adjusting the reactant flow rate, the side reactions and poisoning caused by the reactants staying on the catalyst surface for too long can be reduced.
Catalyst regeneration:
When it is found that the platinum catalyst has a decreased activity due to poisoning, if the degree of poisoning is not particularly serious, some regeneration methods can be tried to restore its activity. For example, in the case of poisoning due to carbon deposits, the carbon deposits on the surface can be burned off by high-temperature calcination in an oxygen or air atmosphere to expose the active sites of the catalyst again; in the case of poisoning due to chemical adsorption, some special chemical reagents can be used for washing and desorption to remove the poisoning substances adsorbed on the surface, but this method needs to be operated with caution to avoid damage to the catalyst itself.