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分光光度法快速测定工业废水中金属离子镍和锌含量的方法研究

时间:2017-04-06 19:47来源:毕业论文
摘要:通过丁二酮肟分光光度法和双硫腙分光光度法可以准确的测定废水中镍和锌的含量。参照国家标准法中镍的测定方法进行条件试验,发现国标法中镍的测定方法,准确度和精确度

摘要:通过丁二酮肟分光光度法和双硫腙分光光度法可以准确的测定废水中镍和锌的含量。参照国家标准法中镍的测定方法进行条件试验,发现国标法中镍的测定方法,准确度和精确度高但稳定性较弱。通过试验,发现丁二酮肟与镍离子形成的水溶性络合物在碱性条件下可以稳定存在,且稳定性强。当加入25%酒石酸钾钠溶液的量为4mL、5%氢氧化钠溶液的量为2.0mL、4%过硫酸铵溶液的量为1.0mL,加入0.5%丁二酮肟溶液的量为4.0mL,在470nm下测定吸光度值,其实验条件最佳。最后,通过回收率试验得出,试验条件较准确。国家标准中锌的测定方法,需要用四氯化碳萃取,并且其显色剂在一定时间内不是很稳定,需放置冰箱保存,且四氯化碳有挥发性,通过试验得出,当PH在4.0-5.0之间时,锌离子与双硫腙生成的红色螯合物在Tween 80 存在的情况下可以稳定的存在,其螯合物为砖红色,当加入乙酸-乙酸钠缓冲溶液的量为5.0mL,硫代硫酸钠溶液的量为1.0mL、0.1%双硫腙-Tween80溶液的量为2.0mL时,显色时间为15min,于534nm波长处测定其吸光度值,其实验条件最佳。关键词:分光光度法;锌;镍;工业废水6876
Rapid determination of the metal ion in industrial wastewater of nickel and zinc by Spectrophotometry
Abstract: Spectrophotometry can accurate determination of nickel and zinc in waste water by Ding two Dimethylglyoxime spectrophotometric method with dithizone. Method for the determination of nickel in according to the national standard method of test condition, found the method for the determination of nickel in national standard method, the accuracy and precision is high but the weak stability. Through the experiment, found two small ketoxime and nickel ions to form soluble complexes can exist stably in alkaline conditions, and strong stability. When adding 25% potassium sodium tartrate solution was 4mL, 5% sodium hydroxide solution was 2.0mL, 4% ammonium sulfate solution was 1.0mL, adding 0.5% D two ketoxime solution for the amount of 4.0mL, the absorbance at 470nm, the optimal experimental conditions. Finally, through the recovery rate experiment, the test results more accurate. Method for determination of zinc in national standard, need to use carbon tetrachloride extraction, and its chromogenic agent in a certain period of time is not very stable, be placed in the refrigerator preservation, carbon tetrachloride is volatile, by experiment, when PH is between 4.0-5.0, red chelate zinc ion and dithizone can exist stably in Tween 80 the presence of the chelate, brick red, when adding acetic acid-sodium acetate buffer solution of 5.0mL, sodium thiosulfate solution for the amount of 1.0mL, 0.1% dithizone solution of -Tween80 was up to 2.0mL, color 15min, was determined at the wavelength of 534nm absorbance value, the optimal experimental conditions.
KeyWords:  spectrophotography; zinc; nickel; industrial waste
 
目  录
1  前言      1
1.1  文献综述        1
1.1.1  锌和镍在人体中的作用   1
1.1.2  锌和镍在工业上的应用   2
1.1.3  工业废水中锌和镍的污染 2
1.2  立体依据、意义及研究内容  3
2  实验部分 5
2.1  试验药品、试剂及仪器      5
2.2  丁二酮肟分光光度法测废水中的镍      5
2.2.1  镍测定实验所需试剂及其配置       5
2.2.2  镍测定试验方法         6
2.3  双硫腙分光光度法测废水中的锌        6
2.3.1   镍测定实验所需试剂及其配置      6
2.3.2   镍测定试验方法        7 分光光度法快速测定工业废水中金属离子镍和锌含量的方法研究:http://www.youerw.com/huaxue/lunwen_4625.html
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