Methods for defluorochlorination during zinc oxide leaching
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During the sulfuric acid leaching of zinc oxide powder, the leachate contains high levels of fluoride and chloride ions. What is an economical method for removing them? Some people suggest using cuprous oxide to remove chlorine – what is the efficiency and speed of this method, and are there any examples? What are the conditions and speed required for the reaction between cuprous chloride and alkalis?
Does your company have copper slag? By adding a certain amount, stirring at an appropriate temperature and pH value, part of the chlorine can be removed to form cuprous chloride.
Chlorine removal using copper slag is a well-established technology, but its efficiency is not very high – 60% is considered a good result. Moreover, copper is lost during the chlorine removal process; however, no one has conducted quantitative studies on this loss. Manufacturers who use this method usually produce their own copper slag, which is considered a metal of no commercial value, so no one cares about the amount of copper lost. Some researchers have made improvements on this technique, enabling **reduction in the amount of copper slag required, while also simplifying the regeneration process and allowing the amount of sodium hydroxide used to be reduced to 20% of the original amount. The regenerated copper slag has a high concentration of active components, resulting in effective chlorine removal. I have also developed another new method for chlorine removal—oxidative chlorine removal, which does not require copper slag, and can achieve a chlorine removal efficiency of up to 70%. I cannot reveal too much details at this time; if you are interested, please contact me at ccfei421@126.com
Study* ah, but fluorine is still a problem, right?
N235 extraction, back-extraction with sodium carbonate solution; for small-scale operations, resin adsorption can be used