Novel technology for the rapid total mineralization of carbon tetrachloride under ambient conditions

Abstract

Polyhaloalkanes such as carbon tetrachloride (CTC) are classified as biorefractory, highly toxic and ozone depleting materials. Those materials are suspected as being carcinogenic and are widespread contaminants in soil and ground water. Accordingly, schemes to effectively destruct and mineralize polyhalomethanes are in great need. We herewith report a novel reagent composed of sodium hydroxide, hydrogen peroxide and a phase transfer catalyst that swiftly and quantitatively mineralize bulk CTC under ambient conditions. We advocate that the key intermediate in the process is the powerful nucleophile, superoxide anion that is extracted by the phase transfer catalyst into the organic (CTC) phase. This nucleophile rapidly reacts with CTC and completely mineralizes it to sodium carbonate and sodium chloride.

Fast and complete in situ mineralization of contaminated soils using a novel method for superoxide generation

“…This reagent was effectively utilized for the destruction of bulk of carbon tetrachloride and other polyhalogen compounds and mineralization of carbondioxide. 24 In this work we demonstrate the effective and rapid reaction of superoxide with various hydrocarbons and other organic contaminants in soil. Beside the advanced oxidizing capacity of the material our reagent is extremely potent nucleophile and it swily reacts (within minutes-hours) at ambient conditions with PCHs, PAHs, PCBs compounds and petroleum products.…”

Carbon Dioxide Capturing for Purifying Hydrogen Generated by Formic Acid Decomposition

“…Sodium hydroxide reacts with hydrogen peroxide to generate superoxide radicals . These radicals react with carbon dioxide and the product is sodium carbonate.…”

Effects of nitroguanidine on the thermal behavior and burning characteristics of 5-amino-1H-tetrazole-based propellants

“…Theoretical propellant performance Thermodynamic parameters for the different formulations were calculated with the commonly used chemical equilibrium method. First, the stoichiometric combustion equation was written according to the Le-Chatelier and Brinkley-Wilson methods with an oxygen balance of zero, as shown in eqn (2) and 3, respectively:…”

“…However, the large amount of byproducts that halocarbon agents generate has been linked to ozone depletion and the use of halons has now been restricted in all countries following the signing of the Montreal Protocol. 1,2 It is therefore urgent to investigate and develop clean and efficient substitute re-extinguishing technologies. Solid propellant gas generators (SPGGs) were rst proposed by Yang and Grosshandler in 1995 and involve solid propellants producing heated gas-phase components that then ignited to extinguish the re mainly by oxygen-starvation.…”