A catalytic converter arrangement for producing phthalic anhydride by means of a gas phase oxidation of aromatic hydrocarbons, comprising a reactor with a gas inlet side for a reactant gas, a gas outlet side for a product gas, a first catalytic converter layer made of catalytic converter elements, and at least one second catalytic converter layer made of catalytic converter elements. The first catalytic converter layer is arranged on the gas inlet side, and the second catalytic converter layer is arranged downstream of the first catalytic converter layer in the gas flow direction. The catalytic converter elements have an outer layer of an active compound. The invention is characterized in that the active compound content in the first catalytic converter layer and/or in the second catalytic converter layer is below 7 wt. %, based on the total weight of the catalytic converter elements, and the ratio of the total surface of the active compound to the volume of the catalytic converter layer is preferably 10000 cm−1 to 20000 cm−1, in each catalytic converter layer.
一种催化转化器排列,用于通过芳香族碳氢化合物的气相氧化来生产
邻苯二甲酸酐,包括一个反应器,具有一个反应气体的进气侧,一个产物气体的出气侧,一个由催化转化器元件制成的第一催化转化器层,以及至少一个由催化转化器元件制成的第二催化转化器层。第一催化转化器层位于进气侧,第二催化转化器层位于气流方向下游的位置。催化转化器元件具有一个活性化合物的外层。该发明的特点在于,第一催化转化器层和/或第二催化转化器层中的活性化合物含量低于催化转化器元件总重量的7wt.%,并且每个催化转化器层中活性化合物的总表面积与催化转化器层的体积的比例优选为10000cm−1至20000cm−1。