Two distinct Langmuir isotherms describe the adsorption of certain salts onto activated carbon over a wide concentration range

Ammonia, cyclohexane, nitrogen and water adsorption capacities of an activated carbon impregnated with increasing amounts of ZnCl2, and designed to chemisorb gaseous NH3 from an air stream

“…The acidic sites of GC were characterized via Boehm titrations. These results and the methodology used have already been published [36]. The number of acidic sites determined using KHCO 3 , K 2 CO 3 and KOH were 0.00, 0.07 and 0.09 mmol/g AC, respectively.…”

“…In the manuscript by Westreich et al, the number of GC adsorption sites for ZnCl 2 adsorption from solution was found to be 3.1 ± 0.3 mmol/g AC [36]. This value is near the loading at which the aggregation of ZnCl 2 molecules starts based on the NH 3 capacity trend reported in Fig.…”

“…In the latter state, ZnCl 2 interacts favorably with activated carbon. The preferential adsorption of ZnCl 2 on GC and the increasing energy of adhesion of ZnCl 2 solutions on graphite with increasing solution concentration have been measured and discussed by Westreich et al [36,38]. Since the impregnant interacts favorably with the activated carbon, the ZnCl 2 impregnated on activated carbon interacts less favorably with NH 3 than bulk ZnCl 2 .…”

Understanding the role of each ingredient in a basic copper carbonate based impregnation recipe for respirator carbons

“…Kuraray GC (referred to subsequently as GC) has a particle mesh size of 12 Â 35, which corresponds to a granule size of approximately 1.70-0.50 mm [8]. Previous work [9] has determined a Brunauer-Emmett-Teller (BET) surface area [10] of approximately 1500 m 2 /g. The impregnating solution [2] was prepared by adding desired amounts of basic copper carbonate (Cu 2 CO 3 (OH) 2 ), ammonium carbonate ((NH 4 ) 2 CO 3 ), ammonium molybdate ((NH 4 ) 2 Mo 2 O 7 ) and ammonium sulfate ((NH 4 ) 2 SO 4 ) to an approximately 0.85:1 ammonium hydroxide and distilled water solution.…”

“…On-carbon samples prepared in this work were impregnated using the imbibing method [9]. A volume of impregnating solution, determined by scaling the 'preferred' patent recipe [2], was added to 10 g of GC in a screw top glass jar.…”