Abstract: A method for manufacturing high purity sulfuric acid is provided. A mixed solution subsequently undergoes a first preheating step, a second preheating step, a distilling step and an evaporating step to remove peroxide, water, oxygen and insoluble impurities, so as to obtain the first gas containing sulfur trioxide, sulfuric acid and hydrogen oxide. And then, the sulfur trioxide is absorbed by a sulfuric acid solution, thereby forming the high purity sulfuric acid.

Abstract: A method for purifying fluoride etching solution is provided. The method begins with a reaction by hydroxide gas or solution to achieve a balance pH condition for the fluoride etching solution. Subsequently, the treated etching solution can be fed by constant velocity pump to a basic anion exchange resin column(s). The basic anion exchange resins remove various contaminants resulting in a saleable product to a wide range of industrial applications. The final solution is collected in a finished product storage tank. The degree of purification by basic anion exchange resin can be verified, if needed at all, thereby making ammonium fluoride (AF), ammonium bifluoride (ABF), anhydrous hydrogen fluoride (AHF) and fluoride mixture to meet the application of industries or different market's application. Further, the ion exchange resins can be regenerated as needed to extend the useful life and system capacity.