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.
Fate and partitioning of heavy metals affected by organic chloride content during a simulated municipal solid waste incineration process
Abstract The effect of organic chloride derived from PVC and other possible sources in wastes, on the partitioning and speciation of heavy metals and their compounds, during Municipal Solid Wastes (MSW) incineration was studied using a laboratory tube furnace and simulated waste spiked with organic chloride. The results indicated that an increase in the organic chloride content and combustion temperature might increase the volatility of heavy metals and/or their compounds in the wastes, thus, increasing metal partitioning in the fly ash or the flue gases. Metal oxides were the major metal species found in the bottom ash, as identified by X‐ray diffraction (XRD) analysis, regardless of the addition of organic chlorides, while several other metal chlorides were also found when spiked at higher concentrations.
Formation and Strength of Magnesia Whiskers
The formation of single-crystal magnesia whiskers during the compressive deformation of single crystals at room temperatures is described. These whiskers can have strengths of the order of millions of pounds per square inch. They are formed during fracture as a result of the discontinuous propagation of cracks which are mechanically relieving internal stresses resulting from plastic flow