SO2 retention over polyarylamide-based activated carbon fibers

The researchers analyze SO2 retention performance of polyarylamide-based AC Fs. Commercial Nomex (R) and Kelvar (R) fibers, as well as fiber rejects fr om the fabrication of Nomex were used as precursors of activated carbon fib ers. Low-density composites produced by agglomeration of carbonized Nomex r ejects with phenolic resin were also activated and analyzed. The SO2 retent ion experiments were carried out both at ambient temperature conditions and at 100 degreesC. A model flue gas, with a composition of 1000-3000 ppm, SO 2 and variable amounts of oxygen and water (N-2 to balance) was used for th e SO2 retention experiments. The SO2 retention capacity of carbonized polya rylamide fibers is very low. Activation of the carbonized fibers considerab ly enhances the performance of these materials. The basic character of the ACFs seems to contribute greatly to the high performance of the fibers towa rds SO2 retention. Nomex and Kevlar-derived ACFs showed a similiar SO2 rete ntion capacity. ACFs derived from carbonization and activation of fiber rej ects present a similar SO2 removal performance to that of ACFs derived from the commercial materials. The activated fiber composites showed a similar retention capacity to that of the loose ACFs, but a lower utilization degre e. The SO2 retention capacity of the polyarylamide-derived ACFs is comparab le to that of commercial PAN-derived ACFs, but the utilization degree is mu ch higher. The SO2 retention performance of the fibers diminishes at some e xtent after several adsorption-thermal regeneration cycles.