In some examples, an air treatment system includes a filter, an ozone sensor, and a separator configured to separate air into a nitrogen-enriched gas and an oxygen-enriched gas. The filter is configured to remove ozone from an air stream and supply filtered air to the separator. The ozone sensor is configured to sense an ozone level of the filtered air issuing from the filter prior to encountering the separator. The air treatment system may include processing circuitry configured to monitor the ozone level sensed. The air treatment system may be part of an inerting system configured to supply the nitrogen-enriched gas to an ullage space of a fuel tank.

A carbonized material, a device for removing ozone, and a method for removing ozone are provided. The carbonized material has at least a carbonyl-containing group, alkylol group, and carbon having sp.sup.2 hybrid orbital. In particular, the at least one carbonyl-containing group has a carbon content from 10 atom % to 30 atom %, based on the total carbon atoms of the at least one carbonyl-containing group, the at least one alkylol group, and the at least one carbon having sp.sup.2 hybrid orbital.

A carbonized material, a device for removing ozone, and a method for removing ozone are provided. The carbonized material has at least a carbonyl-containing group, alkylol group, and carbon having sp.sup.2 hybrid orbital. In particular, the at least one carbonyl-containing group has a carbon content from 10 atom % to 30 atom %, based on the total carbon atoms of the at least one carbonyl-containing group, the at least one alkylol group, and the at least one carbon having sp.sup.2 hybrid orbital.