水泥基材料氯离子测试方法评价研究

氯离子是影响水泥基材料耐久性的重要因素之一,准确测量氯离子浓度,是研究水泥基材料固化氯离子能力的基础.水泥基材料中的掺合料在酸溶时有难溶絮状物质生成,此物质对氯离子有一定的吸附性,导致氯离子测量难度增加.基于此通过实验研究不同测量方法对水泥基材料中氯离子的测量效果.实验分析表明:电位滴定法可以避免人为因素的影响,在保证电极正确处理和仪器定期校准的情况下,测试准确度较高,重复性较好;佛尔哈德法,滴定终点明显,而且滴定准确度高,但操作复杂,可直接用于小批量滴定分析;莫尔法操作简单但准确度不高;氯化银比浊法步骤多且准确度低,但适合快速批处理.

A New Evaluation for Measuring Methods of Chloride Ion Combined In Cement based Materials

Chloride is one of the important factors that affect the durability of cement-based materials.Accurate measurement of chloride ion concentration is important for researching the ability of chloride ion binding in cement-based materials.When cement-based materials was dissolved in acid solution,insoluble flocculent substances may generate which can adsorb some chloride ions and increase the difficulty of accurate measuring chloride ions.Based on this,different measurement methods were adopted for cement-based materials to evaluate the measure effect of chloride ion by experiments.Experiment results show that potentiometric titration is able to avoid the influence of human factors,the accuracy is higher and the repeatability is better,in the case of the electrode was treatment correctly and the instrument was periodic calibration.The titration end point of Volhard method is clear,and the test result is accurate,but the operation is complexity and just suitable for small batch titration analysis.Operation of Mohr method is relatively simple,but the accuracy is not very high.Measurement process of turbidimetry is complex and the accuracy is lower,but it is suitable for handled in batch.