Enhanced dechlorination of chlorobenzene and in situ dry sorption of resultant Cl-compounds by CaO and Na2CO3 sorbent beds incorporated with Fe2O3.
The dechlorination of C(6)H(5)Cl and the in situ dry sorption of Cl-compounds produced by C(6)H(5)Cl decomposition in an alkaline sorbent of CaO or Na(2)CO(3) incorporated with Fe(2)O(3) were studied. A sample gas containing C(6)H(5)Cl at an initial concentration of 500 ppm balanced by either N(2), O(2) (5%)-N(2) or H(2)O (10%)-N(2) carrier gas was introduced into a lab-scale quartz tube reactor where CaO or Na(2)CO(3) sorbent was packed with Fe(2)O(3). Subsequently, the effect of Fe(2)O(3) addition to CaO or Na(2)CO(3) on the removal of C(6)H(5)Cl, achieved by the decomposition of C(6)H(5)Cl as well as the dry sorption of Cl-compounds produced by C(6)H(5)Cl decomposition, was investigated. It was found that the decomposition of C(6)H(5)Cl in CaO or Na(2)CO(3) sorbent bed incorporated with Fe(2)O(3) occurred in the lower temperatures, compared to the case when only CaO or Na(2)CO(3) sorbent bed was used. Thus, Fe(2)O(3) was found to play a catalytic role in the oxidative decomposition of C(6)H(5)Cl. Further, the decomposition of C(6)H(5)Cl in a bed containing only Fe(2)O(3) was promoted by the presence of O(2) and H(2)O in the reaction atmosphere. Moreover, a higher amount of Cl was absorbed in the combined CaO/Fe(2)O(3) and Na(2)CO(3)/Fe(2)O(3) beds, compared to the absorption of Cl-compounds in only CaO or Na(2)CO(3) sorbent bed. Finally, the comparison of CaO and Na(2)CO(3) sorbents showed that the decomposition of C(6)H(5)Cl and the in situ dry sorption of the resultant Cl-compounds in the combined Na(2)CO(3) and Fe(2)O(3) beds were higher than those in the combined CaO and Fe(2)O(3) beds.
Matsuda
H
H
Department of Energy Engineering and Science, Nagoya University, Nagoya, Japan.
Ito
T
T
Kuchar
D
D
Tanahashi
N
N
Watanabe
C
C
D000327:Adsorption; D017610:Calcium Compounds / Q000737:chemistry*; D002254:Carbonates / Q000737:chemistry*; D017606:Chlorine Compounds / Q000737:chemistry*; D002722:Chlorobenzenes / Q000737:chemistry*; D002849:Chromatography, Gas; D004785:Environmental Pollutants / Q000737:chemistry*; D004787:Environmental Pollution / Q000517:prevention & control*; D005290:Ferric Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*
D017610:Calcium Compounds; D002254:Carbonates; D017606:Chlorine Compounds; D002722:Chlorobenzenes; D004785:Environmental Pollutants; D005290:Ferric Compounds; D010087:Oxides; C000499:ferric oxide; C005686:sodium carbonate; C016538:lime; C031294:chlorobenzene