Thread Content
Components of this solution: 5 moles of sodium hydroxide, along with lead, aluminum, and zinc. This method was derived from my practical experience; please give me your advice. Take 5 milliliters of the solution (a smaller amount can be used when the lead content is high, and a larger amount when it is low; however, using too much of this solution will result in waste of EDTA solution during titration). However, this can help compensate for errors.) Add 80 milliliters of 25% sulfuric acid solution; (previous textbooks specified 10 milliliters. This amount is sufficient for acidic solutions, but with strong alkaline solutions, less amount will not be enough to neutralize the base, and at low acidity levels, zinc hydroxide and aluminum hydroxide will precipitate, affecting the measurement. Therefore, more of this solution is added to make it acidic, thereby dissolving zinc hydroxide and aluminum hydroxide.) Heat to a boil for 5 minutes, allow the precipitate to form for 20 minutes, then filter. Wash the filter three times with 2% sulfuric acid, after which rinse the filtered precipitate with water back into the original container. Place both the precipitate and the filter paper in the container, add 50–70 milliliters of an acetic acid and sodium acetate buffer solution with a concentration of around 5.4, to dissolve lead sulfate. Add xylene orange as an indicator, a small amount of VC, and then titrate using EDTA. Since we have real-time monitoring in the factory, this analysis meets the requirements and is ideal for us. *quan168@sina.com