Effect of hydrogenation refining catalyst temperature and temperature rise on sulfur content
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Hydrofining catalyst, for adjusting the sulfur content in gasoline. Which has a more significant and quicker effect: maintaining the inlet temperature, reducing the amount of quench hydrogen, increasing the overall bed temperature rise and raising the inlet temperature, or adjusting the amount of quench hydrogen added while maintaining the original temperature rise?
The bed temperature is within the designed range; increasing the bed temperature can help save energy and improve conversion rates. However, this may accelerate the deactivation of the catalyst in the lower layers of the bed, which is not favorable for the long-term operation of the facility. Yet this method is quick – in hydrogenation processes, conversion rates are generally increased by raising the inlet temperature and then ensuring an even temperature increase across all layers of the bed.
Fluctuations of a few degrees in the reactor inlet temperature can cause a significant increase in the temperature of the upper bed layer, which in turn requires more quench hydrogen to stabilize the temperature at the inlet of the lower bed layer, thereby increasing energy consumption. Will the increase in temperature of the upper layer accelerate the deactivation of the catalyst in that upper layer?
Hydrogenation units are more or less the same; I work in hydrocracking, and sulfides can be removed quite easily. If there is a change in the overall feedstock, it’s generally necessary to increase the temperature starting from the inlet, raising the temperature throughout the reactor, so as to maintain a consistent rate of catalyst deactivation. In fact, it’s not recommended to increase the temperature only for one specific bed in the reactor. Secondly, the more desulfurization is carried out, the higher the temperature rise; keeping the temperature rise constant will not improve the effectiveness.
1. Quench hydrogen is a means of controlling runaway temperature; it shouldn’t be used in this way! The opening degree of the quench hydrogen valve for many units is very small. 2. If adjusted in this way, the grading effect of the catalyst will not be fully utilized, right? ； Before the catalyst in the upper layer can exert its activity, the catalyst in the lower layer has already become clogged and deactivated.
The catalyst exhibits high initial activity. The gasoline we process is obtained through catalytic cracking and has a high olefin content; the fractionation at the early stages of the processing unit is not optimal. Therefore, quench hydrogen must be used every day to keep the temperature rise in the bed below 30 degrees. Prevent excessive temperature rise from causing catalytic deactivation. Today’s catalysts are much more resistant to degradation than before, but the requirements regarding temperature rise control are becoming increasingly strict
I haven’t worked with hydrocracking, so I don’t know. On our end, it’s hydrogenation refining; I really haven’t heard of this method before.
It is best to increase the inlet temperature; raising the temperature of the upper bed layer can improve the comprehensive utilization performance of the catalyst. Simply increasing the temperature of the lower bed is not conducive to the long-term operation of the catalyst.
“Xunkai Catalysts boasts a comprehensive range of hydrogenation catalyst products, including those based on Raney nickel, supported nickel, copper-zinc, copper-silicon systems, as well as catalysts on precious metal carriers – both in powder form and for fixed-bed use. These catalysts have been successfully applied in processes such as hydrogenation, dehydrogenation, reductive amination, and desulfurization across industries including those involved in 1,4-butanediol, caprolactam, fatty alcohols, organic amines, butyl octanol, HPPO, petroleum resins, dye intermediates, as well as pharmaceutical and pesticide intermediates. For technical inquiries, please contact Manager Mei at 17701646014