Reactor for carrying out a chemical reaction

A reactor for carrying out a chemical reaction in a process fluid using multiphase alternating current in order to heat the process fluid, wherein the alternating current has a number M of phases, wherein M is an integer greater than one, comprising:

• a reactor vessel formed by a thermally insulating reactor wall;
• at least one group having multiple reaction tubes, wherein each group comprises M reaction tubes, each of which has an electrically heatable heating section that extends between a first and a second removal region of the respective reaction tube for a respective heating length, wherein the heating sections are arranged at least for 95% of their heating length within the reactor vessel and each have a feed region in a region which extends over 20% to 80% of the heating length of said heating section;
• electrically conductive feed elements, wherein each group of reaction tubes is paired with feed elements which are electrically conductively connected to the feed regions of the group, and different phases of the alternating current can be fed to different feed elements paired with a respective group;
• electrically conductive first and second removal elements, each group being paired with M first removal elements and M second removal elements which are electrically conductively connected to the first removal regions or second removal regions of the group;
• and
• at least one electrically conductive first star bridge and at least one electrically conductive second star bridge, wherein each group is paired with a respective first and a second star bridge, wherein for each group, the first removal elements paired with the group are electrically conductively connected to the first star bridge paired with the group, and the second removal elements paired with the group are electrically conductively connected to the second star bridge paired with the group.