关于铁离子稳定剂稳定铁离子能力的检测方法的改进

Improvement of Detection Method for Stabilizing Power of Iron Ion Stabilizer

稳定铁离子能力是评价铁离子稳定剂的重要指标之一。为了提高检测方法的时效性,提出了检测稳定铁离子能力的新方法。检测采用质量分数为5%的样品浓度,先加入5mg/mL的高浓度铁离子标准溶液,用碳酸钠溶液调节pH值观察后,再加入0.5mg/mL的低浓度铁离子标准溶液的检测方式。为了尽可能减小调pH值所加入的碳酸钠溶液的体积,将标准中仅用质量分数为5%碳酸钠溶液调节pH值调整为先用质量分数为15%碳酸钠溶液调节pH值到3.5左右,再用5%碳酸钠溶液微调至4.0~5.0。方法改进后,检测结果的相对偏差维持在1.0%以内,满足相对偏差要求,且时效性高。

The stabilizing power of iron ion stabilizer is one of the important indexes to evaluate the iron ion stabilizer. In order to im-prove the timeliness of detection methods, a new method to detect the stabilizing power of iron ion was proposed. In detection, highconcentration of iron ion standard solution of 5 mgfmL was added to the sample of 5%, the pH value of the sample was adjusted byusing sodium carbonate solution, and then the low concentration of iron ion standard solution of 0.5 mg/mL was added to the sample.In order to reduce the volume of sodium carbonate solution for adjustment of the pH value of the sample, the adjustment of the pHvalue of the sample using the sodium carbonate solution of 5% used in standard is replaced by adjusting the pH value to about 3.5using the sodium carbonate solution of 15% and then adjusting the pH value to 4.0-5.0 using the sodium carbonate solution of 5vA..After the improvement, the relative error of the test results is less than 1%, which meets the requirement of relative error, and the newdetection method is of high timeliness.