Chloride determination by ion chromatography in petroleum coke after digestion by microwave-induced combustion.
Microwave-induced combustion was applied to petroleum coke digestion in closed vessels for further chloride determination by ion chromatography. Samples were pressed as pellets and placed on a quartz holder. Combustion was performed using oxygen pressure of 2 MPa and 50 microl of 6 moll(-1) NH(4)NO(3) as aid for ignition. Recoveries from 97 to 102% were obtained for all studied absorbing solutions (water, H(2)O(2), Na(2)CO(3) or (NH(4))(2)CO(3)). Accuracy was evaluated using certified reference materials with agreement better than 98% using water as absorbing solution with reflux step. The limit of quantification was 3.8 microg g(-1).
Pereira
Juliana S F
JS
Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
Diehl
Liange O
LO
Duarte
Fábio A
FA
Santos
Maria F P
MF
Guimarães
Regina C L
RC
Dressler
Valderi L
VL
Flores
Erico M M
EM
D002712:Chlorides / Q000032:analysis*; D003077:Coke / Q000032:analysis*; D008872:Microwaves; D010578:Petroleum / Q000032:analysis
D002712:Chlorides; D003077:Coke; D010578:Petroleum