How to determine catalyst loss in an MTBE reactor

Loose installation of the catalyst support or stainless steel mesh at the bottom of the reactor, along with other factors, can cause the catalyst to leak out from the bottom of the reactor. Generally speaking, catalyst loss occurs as it moves downstream along with the reaction material through very small pores, and this process continues, leading to significant amounts of catalyst loss. How can we determine whether the catalyst in the reactor has been lost? There are several phenomena as follows: ① After the catalyst leaks out of the reactor, the temperature distribution within the reactor becomes uneven. After increasing the reactor inlet temperature, the bed temperature rises only slightly, the reaction efficiency decreases, and it may even fail to meet the reaction requirements. ②After the catalyst in the reactor is lost, it falls to the bottom of the azeotropic distillation column (or catalytic distillation column). The temperature at the bottom of the column is relatively high (around 130°C); under these conditions, the MTBE present in the bottom of the column undergoes a decomposition reaction when in contact with the catalyst, resulting in the formation of methanol and isobutylene in the MTBE product. ③When sampling and discharging at the bottom of the tower reactor, catalyst particles can be found. If catalyst loss is confirmed, immediate action should be taken to prevent it from worsening. Generally, the vehicle should be stopped immediately to check the location and amount of catalyst loss. Then, the catalyst is removed, the cause of the loss is identified, remedial actions are taken, and an adequate amount of catalyst is reinstalled. Clean the pipes and equipment through which the lost catalyst passed, add a passivator, and restart the operation. If the catalyst is not lost in large quantities, but rather only in the form of tiny particles that reach the bottom of the downstream tower, trace amounts of isobutylene and methanol may appear in the MTBE product at the bottom of the tower. In such cases, it is not necessary to shut down the plant; instead, an appropriate amount of passivator can be added through the spare inlet in the retention section of the tower, thereby rendering these tiny catalyst particles inactive.

The MTBE product is contaminated, or there are excessive levels of methanol and isobutylene in the bottom of the catalytic distillation column

There will definitely be some loss due to running, and we determine when to replace the catalyst by observing the changes and trends in the temperature inside the reactor to assess whether the catalyst has become ineffective