title: Chloride determination by ion chromatography in petroleum coke after digestion by microwave-induced combustion.
abstract: 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).
authors.affiliation: Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Juliana S F
authors.initials: JS
authors.lastname: Pereira
authors.forename: Liange O
authors.initials: LO
authors.lastname: Diehl
authors.forename: Fábio A
authors.initials: FA
authors.lastname: Duarte
authors.forename: Maria F P
authors.initials: MF
authors.lastname: Santos
authors.forename: Regina C L
authors.initials: RC
authors.lastname: Guimarães
authors.forename: Valderi L
authors.initials: VL
authors.lastname: Dressler
authors.forename: Erico M M
authors.initials: EM
authors.lastname: Flores
mesh_terms: D002712:Chlorides / Q000032:analysis*; D003077:Coke / Q000032:analysis*; D008872:Microwaves; D010578:Petroleum / Q000032:analysis
chemical_list: D002712:Chlorides; D003077:Coke; D010578:Petroleum