洛阳理工学院毕业设计（论文）
镁铬砖耐火材料生产过程中六价铬的检测及公害评价
摘 要
含铬耐火材料由于具有优良的抗侵蚀性，在玻璃、水泥、石化以及钢铁等行业广泛应用。然而由于含铬耐火材料生产、使用及用后会有六价铬的生成，对生态环境及人类健康造成严重危害。但目前含铬耐火材料仍具有不可替代的作用。所以，对于含铬耐火材料生产过程中的污染控制就尤为重要。
本文采用了水溶法把六价铬从试样中分离出来，然后，用硫磷混合酸溶解分离过六价铬后的试样，这样就可以把镁铬砖试样中的三价铬和六价铬分离开。并采用了硫酸亚铁铵滴定法来测定镁铬砖中三价铬和总铬的含量，用二苯碳酰二肼分光光度法、铬的亚甲基蓝分光光度法、碘化钾——淀粉体系光度法重点测定了六价铬的含量，并对六价铬的污染及其控制做了进一步的分析与讨论。
关键词：镁铬砖、六价铬、混合酸溶、分光光度法、滴定法
I
洛阳理工学院毕业设计（论文）
Detection and pollution evaluation of six valence chromium production process of magnesite chrome bricks in the refractory
ABSTRACT
Chrome refractory material has excellent corrosion resistance, widely used in glass, cement, petrochemical and steel industries. However, due to the generation of chrome refractories production, use and after use will have six valence chromium, causing serious damage to the ecological environment and human health. But the chrome refractories still has an irreplaceable role. Therefore, it is particularly important for pollution control of the production process of chromium in the refractory.
This paper adopts the solution to six chromium separated from the sample, and then, the separation of specimen six chromium after parathion mixed acid solution with, so you can put the trivalent chrome magnesite-chrome brick specimens and six chromium. Content and adopts the ammonium ferrous sulfate titrimetric method to determination of trivalent chromium and total chromium in magnesia chrome brick, with two benzene carbonyl two hydrazine spectrophotometry, chromium methylene blue spectrophotometry, potassium iodide spectrophotometric determination of starch -- focus on the six valence chromium content, and the six valence chromium pollution and its control are analyzed and discussed further.
KEY WORDS: magnesium-chrome brick, six valence chromium, mixed acid, spectrophotometry, titration
II
洛阳理工学院毕业设计（论文）
目 录
前 言 ................................................................................................ 1 第1章 镁铬砖的应用现状及应用前景 ............................................ 2
1.1 含铬耐火材料应用 ............................................................... 2 1.2 含铬耐火材料的应用现状 ................................................... 2 1.3 含铬耐火材料的发展前景 ................................................... 4 第2章 镁铬砖样品中三价铬及总铬含量的测定 ............................ 5
2.1 样品的预处理 ....................................................................... 5 2.2 硫酸亚铁铵滴定法 ............................................................... 5
2.1.1 实验原理 ..................................................................... 5 2.1.2 试剂与仪器 ................................................................. 6 2.1.3 样品的测定 ................................................................. 6 2.1.4 数据处理 ..................................................................... 7 2.1.5 结果与讨论 ................................................................. 8
第3章 六价铬的测定 ....................................................................... 9
3.1 二苯碳酰二肼分光光度法 ................................................... 9
3.1.1 实验原理 ..................................................................... 9 3.1.2 试剂和仪器 ................................................................. 9 3.1.3 显色剂的配置 ........................................................... 10 3.1.4 样品的测定 ............................................................... 10 3.1.4 数据处理 ................................................................... 10 3.1.5 结果与讨论 ............................................................... 12 3.2 铬的亚甲基蓝分光光度法 ................................................. 13
3.2.1 实验原理 ................................................................... 13 3.2.2 试剂与仪器 ............................................................... 13 3.2.3 样品的测定 ............................................................... 14 3.2.4 数据处理 ................................................................... 15 3.2.5 结果与讨论 ............................................................... 16 3.3 碘化钾-淀粉体系光度法 .................................................... 18
III
洛阳理工学院毕业设计（论文）
3.3.1 实验原理 ................................................................... 18 3.3.2 试剂与仪器 ............................................................... 18 3.3.3 样品的测定 ............................................................... 19 3.3.4 数据处理 ................................................................... 19 3.3.5 结果与讨论 ............................................................... 21 3.4 三种分光光度法的比较 ..................................................... 23 第4章 六价铬的公害评价 ............................................................. 24
4.1 六价铬的危害 ..................................................................... 24 4.2 镁铬砖生产工艺 ................................................................. 24 4.3 六价铬产生途径 ................................................................. 26 4.4 六价铬的生成与其环境影响 .............................................. 28 第5章 镁铬砖耐火材料六价铬污染控制及对策 .......................... 29
5.1 倡导无铬化的原因 ............................................................. 29 5.2 六价铬的污染控制 ............................................................. 30
5.2.1 酸性氧化物 ............................................................... 30 5.2.2 温度的控制 ............................................................... 30
结 论 .............................................................................................. 32 谢 辞 ................................................................................................ 33 参考文献 .......................................................................................... 34 外文资料翻译 .................................................................................. 37
IV
