Why is it particularly important to pay close attention to changes in the catalyst chlorine content of the last reforming reactor during operation?

Thread Content

During the reforming reaction process, the most challenging task is carried out by the last reactor, which contains approximately 50% of the total catalyst volume. It operates under high temperatures and low space velocities at high intensity to carry out the alkanes dehydrogenation and cyclization reactions, thereby increasing the production of aromatics. Therefore, changes in the chlorine content of the catalyst in this reactor play a crucial role in the reforming reaction process. Due to the special tasks assigned to this reactor, a higher chlorine content is usually required. However, since the chlorine addition rate in each reactor is usually the same during normal operation, while the actual chlorine content in each reactor decreases, this results in a situation where the catalyst in the last reactor requires a higher chlorine content than actually available, preventing the catalyst from performing optimally and thus hindering it from fulfilling its tasks effectively. To resolve this contradiction, when it was found that the bed temperature drop in the last reactor was significant and that the chlorine content in the catalyst was insufficient, chlorine was added in large quantities to that reactor in order to adjust the chlorine content of the catalyst to the required level and restore its activity. Using increased temperature to compensate for this decrease in activity will have the opposite effect.