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BTEX and two chemical warfare simulants, half mustard and dissopropylmethyl phosphonate, are placed in water and adsorbed into fiberglass supported activated carbon filters. Removal of the contaminants, the pressure drops of the filters, and the regeneration of the FGAC filter is graphed.

Research indicates that photocatalytic reduction of halogenated benzene derivatives is possible. As a result, a decrease in toxicity is achieved. Accompanying charts and graphs provide additional statistical data.

University researchers investigated the sorption of ionizable organic solutes such as benzene, phenol and aniline on surfactant-modified zeolite.

Experiments on the absorption of toluene, 0-xylene and benzene to wood are described. The results could be used to help predict organic contaminant transport at landfills, which often contain up to 25% wood waste by weight.

Study of the effects of airflow rate, air channel spacing, and porous media type on NAPL removal, using a lab-scale reactor with vertical air channels. Increased channel spacing caused the NAPL removal efficiency to decrease.

A study investigates the rate-limited sorption of homologous series hydrophobic organic compounds such as polycyclic aromatic hydrocarbons, alkylated benzenes, chlorinated benzenes and chlorinated alkenes by two soils with humic and fulvic acid. Results revealed that the solutes sorbed more strongly to the humic-dominated soil than the fulvic-dominated soil. Sorbate shape and structure appear to have a secondary influence on the total equilibrium sorption.

Recent studies have proven that the presence of organohalogens in relatively unpolluted environments are caused by the natural halogenation of organic macromolecules. No evidence of chlorinated aromatic structures can be found in samples taken from fresh plant matter. The two samples, fresh and decaying plant materials which were isolated by acidic solvolysis and spruce forest and meadow grass soil samples with high molecular weight, yielded several benzoic acid derivatives after undergoing oxidative degradation.

Stable carbon isotopic analysis is an ideal tool for the remediation of contaminants such as benzene, toluene, ethylbenzene and xylenes (BETX). The process was effective in determining the concentrations and stable isotope values of BETX at a gasoline-contaminated site in southern California. The method, whereby purge-and-trap is connected to a gas chromatograph/ion trap mass spectrometer system, yielded varying concentrations of BETX that range from below detectable to highly detectable levels. Results indicate that toluene usually yield the highest concentrations.

The chlorination of resorcinol through dichlororesorcinol was evaluated using a series of chlorine-substituted resorcinol substrates. Their initial chlorination kinetics were examined over the pH range of two to 12 at 12 degrees Celsius. The apparent chlorination rates for each of the resorcinol substrates are a minimum in the pH range of three to six and a maximum in the pH range of eight to 11. A mechanism involving the reaction of HOCl with ArX(OH)2, ArX(OH)O- and ArX(O-)2 and an acid-catalyzed pathway at pH

A study was conducted on the heterogeneous combustion reactions of non-chlorinated C2 aliphatics. Acetylene was reacted with HCl/air between 300-600 degrees centigrade. Catalyst SiO2/metal oxide mixtures were then compared with municipal waste incinerator fly ash. Catalytic reaction of C2 aliphatic compounds at 600 degrees centigrade was found to have a significant contribution to the production of chlorination and nonchlorinated aromatic compounds in combustion processes.

The oxide-chloride exchange during the adsorption of chlorinated benzenes on magnesium oxide and calcium oxide particles with large surface areas were observed. The results showed the key role played by magnesium oxide, calcium oxide and the use of hydrogen as the flow gas in lowering the allowable temperature for the complete decompostion of chloroarenes. It also revealed the absence of chlorine-containing volatile product emissions from the magnesium oxide reactor bed.

An atmospheric pressure ionization (API) source used with tandem mass spectrometry is effective in measuring dilute hydrocarbons in automobile exhaust. An API source and a triple quadrupole spectrometer can measure benzene and toluene at real-time rates as high as 100 hertz. In contrast, a low-pressure chemical ionization source used with tandem mass spectrometry is less sensitive than the API source method.

Experiments were conducted on a fluidized-bed reactor to investigate the effect of the flue gas temperature on the creation of chlorinated aromatic compunds during post-combustion in a solid waste incinerator. The study revealed the formation of polychlorinated dibenzo-p-dioxins, dibenzofurans, benzenes and biphenyls. It also demonstrated the existence of the four compounds as a function of both flue gas temperature and residence time in the reactor's cooling compartment.