Pilot-Plant Study of the PCB Degradation at Ambient Temperature and Pressure

Abstract

A continuous pilot plant for the degradation of polychlorinated biphenyls (PCBs) by the palladium on carbon (Pd/C)-catalyzed hydrogenation in the presence of triethylamine was designed and constructed. Both undiluted PCBs obtained from a capacitor and diluted PCBs with desulfurized trans oil were smoothly decomposed at ambient temperature and pressure. Desulfurization of the trans oil was found to be essential for the efficient degradation due to the possible deactivation of the Pd/C by catalysis poisoning due to the sulfur-containing materials in the oil. The combined use of the present degradation method and the catalytic desulfurization technology for the purification of gasoline and kerosene could be used in practical applications.

Development of the Applications of Palladium on Charcoal in Organic Synthesis

“…In 2008, Sajiki's group reported a Pd/C‐Et 3 N system for the hydrodechlorination reaction of polychlorinated biphenyls under ambient hydrogen pressure and room temperature [Eq. (56)] . Fifteen kinds of polychlorinated biphenyls congeners, including highly toxic co‐planar ones, were smoothly dechlorinated to biphenyl under the Pd/C‐Et 3 N‐H 2 system.…”

Practical Chain‐End Reduction of Polymers Obtained with ATRP

“…Importantly, the products are frequently obtained in quantitative yields after simple filtration. The heterogeneous catalysts employed in the dehalogenation reactions have been shown to be recoverable and the process scaled to multiton levels . Given the mild and high yielding nature of these reactions, we were interested if the robustness and generality of this approach could be extended to the clean and selective reduction of halogen chain‐ends of polymers prepared using ATRP and copper (0)‐mediated RDRP techniques.…”

Hydrodechlorination of Aroclor 1260 in Aqueous Two-phase Mixture Catalyzed by Biogenerated Bimetallic Catalysts

“…However, palladium is very sensitive to deactivation, especially in waste-waters, due to its sequestration and precipitation with suspended organic matter. In addition, loss of Pd(0) reactivity is mostly due to hydrogen sulfide (H 2 S and HS − ), which is ubiquitous in anoxic ecosystem [5,6]. For these reasons, Pd-based catalysts are rarely used for applications in water treatment.…”