Determination of chlorine and bromine in automotive shredder residues by oxygen bomb and ion chromatography
An analytical procedure, oxygen bomb combustion-ion chromatography (IC), has been developed for the determination of total chlorine in Automotive Shredder Residues (ASR). Samples of these residues are fired under elevated oxygen pressure (30 atm) and the combustion products are transferred into a Na2 CO3/NaHCO3 absorbent solution containing 1% of H2 O2; the chlorine contents are then evaluated by ion chromatography. The use of the non-suppressed IC determination with a conductivity detector provides a rapid, sensitive and selective method for chlorine determination in ASR, allowing determinations of this heteroatom at levels below 1% in the presence of bromine and sulfur. Moreover, the proposed method allows the simultaneous determination of chlorine, bromine and sulfur which are potential environmental hazards.
Origins Of Chlorine In MSW And RDF:Species And Analytical Methods
The chlorine content of municipal solid waste (MSW) and refuse derived fuel (RDF) plays a dominant role in combustion processes. In order to prevent operational problems, such as high temperature corrosion, quality assured analytical methods for the determination of the chlorine concentration are necessary. This paper presents results of the chlorine content of the main components of untreated municipal solid waste. Various analytical methods have been compared with samples with a differing matrix and chlorine speciation. The comparison intends to not only estimate overall content of chlorine in mixed waste, but also to clarify chlorine species/origin in various components which have further influence on chlorine thermal behavior during combustion.
Multiple-dose pharmacokinetics of moxisylyte after oral administration to healthy volunteers.
The pharmacokinetics of moxisylyte in plasma and urine was investigated after oral administration. Twelve subjects were treated orally, twice daily with 240 mg of the drug for 6 days; on day 7, the subjects received a last dose of 240 mg of moxisylyte. Moxisylyte was assayed in plasma and urine by a specific HPLC method with fluorimetric detection. Moxisylyte was absorbed rapidly and changed to its metabolites immediately after drug administration; unchanged moxisylyte was not found in plasma. Two metabolites were found in plasma and urine: conjugated desacetylmoxisylyte (DAM) and the conjugate of desmethylated DAM (MDAM). The pharmacokinetic parameters determined after the first oral administration were not modified on multiple dosing. The apparent elimination half-lives of conjugated DAM and MDAM were 2.3 and 3.5 h, respectively. Elimination of these two metabolites in urine averaged 50 and 10%, respectively.