Active filter element for end face incident flow

A filter element for end face incident flow comprising:

• at least one flat layer of gas-permeable filter material alternating with at least one pleated layer of gas-permeable filter material to form channels having an open cross section, a first group of said channels being tightly sealed at one end and a second group of said channels being tightly sealed at an opposite end such that a fluid flowing through the filter from an incident flow side defined by one end face to a discharge side defined by an opposite end face must pass through one of said filter material layers to filter the fluid, and
• a seal for sealing the incident flow side from the discharge side at an installation site of the filter element, wherein
• each side forming the open cross section of the channels of the first group which are spaced from the periphery of the filter element is bounded by a channel of the second group such that the fluid can flow through the full area of the channels of the first group, except for the fold edges of the channels;
• at least one group of channels is filled with adsorbent particles and sealed by a gas-permeable medium disposed over the corresponding end face of the filter element, and
• the particle size of the adsorbent material is larger than the pore size of the gas-permeable medium.