Enhanced dechlorination of chlorobenzene by microwave-induced zero-valent iron: particle effects and activation energy

Abstract

Organic compounds such as chlorobenzene cannot be effectively decomposed with currently available biological and chemical treatment methods. Preliminary studies show that nano-scale zero-valent iron particles irradiated by microwave is effective in decomposing chemically refractive organic compounds such as chlorobenzene. In this study, microwave is applied to enhance chlorobenzene removal using micron-scale iron particles and nano-scale zero-valent iron particles suspended in the chlorobenzene solution as the dielectric media. The results show that better chlorobenzene removal can be achieved when the chlorobenzene solution is irradiated with 250 W microwave for 150 s than without microwave irradiation. The microwave radiation increases iron reaction rate and surface activity, thus enhancing the chlorobenzene removal. The microwave-induced iron particles cause the chlorobenzene activation energy to drop 34.0% for micronscale iron and 16.1% for nano-scale zero-valent iron. They can remove 13.6 times more chlorobenzene for micro iron, and 3.6 times more chlorobenzene for nano iron. We have demonstrated that the microwave-induced nano-scale iron particles are effective in treating toxic organic substances as demonstrated in this laboratory study.

Enhanced oxidative degradation of tetracycline by visible light-promoted g-C3N4 modified Cu3(OH)4SO4/Cu7S4 composites under an air atmosphere

“…1,3,6,7 Among these methods, AOPs (such as electrochemical oxidation, ultrasonic degradation, photocatalysis, microwave irradiation, Fenton/Fenton-like oxidation and so on) have proven a good application for the treatment of refractory organic pollutants in the environment. [8][9][10][11][12][13][14][15] Currently, the conventional peroxymonosulfate (PMS) and H 2 O 2 activation processes based on AOPs by transition metals or UV irradiation are gaining researchers' attention. 16,17 However, using dissolved oxygen (O 2 ) as an environmentally safe oxidant to generate radical or anionic reactive oxygen species (ROS: OH, O 2 À , and 1 O 2 ) has been rarely reported to remove refractory organics in wastewater or groundwater.…”

Interfacial Electrostatic Field Boosted Exciton Dissociation of Phosphorylated BiOBr for Efficient O2 Activation and Chlorobenzene Degradation

“…As one of the most common aromatic Cl-VOCs, chlorobenzene is highly deleterious to humans. , As a result, the chlorobenzene is mandated as a priority pollutant by the United States Environmental Protection Agency (USEPA). Several technologies have been adopted to remove chlorobenzene from the environment, such as physical adsorption, , pyrolysis, , biodegradation, , and advanced oxidation processes (AOP), including electrochemical oxidation, microwave irradiation, , ultrasonic degradation, photocatalysis, , Fenton/Fenton-like oxidation, , and ozonation/peroxone oxidation. − Among these AOPs, semiconductor photocatalysis receives much attention because of its fossil/electricity-free and environmental-friendly characteristics, by activating the atmospheric molecular oxygen (O 2 ) to the favorable ROS (·O – , ·O 2 – , H 2 O 2 , ·OH, or 1 O 2 ). − …”

Syngas Formation by Microwave-induced Platinum/Palladium/Rhodium Spent Catalyst

“…(13)(14)(15)(16) Microwave heat treatment technology has been successfully applied in different fields, such as removing volatile pollutants, (18) oil-water separation, (19) and treatment of halogen organic pollutants with the assistance of catalysts (nanoscale zero-valent Copper, iron, and titanium dioxide). (20)(21)(22) In this study, a Pt/Pd/Rh spent catalyst combined with micron iron powder was used to produce syngas by the partial oxidation of methane. The micron iron powder with a high dielectric constant was used to absorb microwave energy to convert it into heat energy, which was used as the heat source for syngas production and help increase the yield of production.…”