Abstract

A method for concentrating and/or entrapping radioisotopes from an aqueous solution, said method comprises mixing the aqueous solutions with at least one inorganic salt under conditions in which said salt forms at least one stable hydrate, incorporating the tritium as water of crystallisation. Said hydrate will neither react nor degrade for extended periods of time, and accordingly a method of stabilising large amount of radioactive waste is provided.

IPC Classes  ?

• G21F 9/04 - Treating liquids
• B01D 59/26 - Separation by extracting by sorption, i.e. absorption, adsorption, persorption
• G21F 9/12 - Processing by absorptionProcessing by adsorptionProcessing by ion-exchange

Abstract

An improved method of controlling air pollution, a combustion gas is passed through a solution of an alkaline-earth metal sulfide and a redox buffer (e.g., a mono alkaline-earth metal phosphate salt), preferably but not essentially in combination with an alkaline-earth metal carbonate FGD system. The reagents are provided in a fully soluble form enabling low cost application and retrofitting of existing facilities whilst also including alkaline-earth bases salts, which advantageously afford stability to the process product. The reagents co-precipitiate when the solution achieves a pH of 4.5 to 6.5 such as is encountered in the acidic environment in conduits that carry combustion flue gases.

IPC Classes  ?

• B01D 53/64 - Heavy metals or compounds thereof, e.g. mercury
• A62D 3/33 - Processes for making harmful chemical substances harmless, or less harmful, by effecting a chemical change in the substances by reacting with chemical agents by chemically fixing the harmful substance, e.g. by chelation or complexation