Assessment of zirconium species distributions in Zr-F-H aqueous solution based on thermodynamics

摘要

The zirconium based conversion coatings can be formed by modified aqueous bath of hexafluorozirconic acid. Thus understanding the relationship of zirconium species distributions in aqueous solution at different conditions is important for controlling the properties of precursors in the aqueous chemistry of Zr-F-H. Many data can be found in the literature for the hydrolysis and complexation of zirconium. This paper presents a description of the distributions of zirconium inorganic species as a function of pH and free fluoride concentration involved by mathematical expression and graph. The objective of the assessment is to provide a simple quantitative mean of obtaining zirconium species distributions with the variations of pH and free F~-, so that the zirconium species could be controlled.