Kinetics of iron colloid substance destruction while interacting with carbon dioxide

Abstract

The study of iron colloid substance destruction in order to obtain the kinetic parameters is relevant for water treatment technologies. The aim of the research is to study the kinetics of iron colloid substance destruction influenced by carbon dioxide for practical use of this method in water treatment technologies for water purification step. Methods: photocolorimeter, chromatography, pH-meter, titrometry. Results: The authors have investigated iron colloid substance destruction while interacting with carbon dioxide. The process consists of the carbon dioxide absorption, destruction colloid substances followed by spontaneous precipitation of a Fe(OH)3 and desorption of CO2 from the solution. It was ascertained that the time of carbon dioxide absorption by iron colloid solution is 30 seconds, while destruction of colloids is 120 min; the time of CO2 desorption at different ways of processing solution was determined. The paper shows the defining role of organic humic substances and silicon compounds in destruction of iron colloid substances.their distabilization at pH of 4,5 allows coagulation occurrence to form a precipitate in the form of iron hydroxide (III). The activation energy of colloid substance destruction is 37,0 kJ/mol. It indicates the simultaneous limitation of this step due to the carbon dioxide diffusion and chemical reaction of its interaction with iron colloid substances.

Keywords

• kinetics
• iron colloid substances
• carbon dioxide
• groundwater