常壓微波消解分光光度法測定COD的研究.pdf

1、南京工業(yè)大學(xué)碩士學(xué)位論文常壓微波消解分光光度法測定COD的研究姓名：蔡文艷申請學(xué)位級別：碩士專業(yè)：應(yīng)用化學(xué)指導(dǎo)教師：俞斌20060510Ⅱ ABSTRACT A method for the spectrometric determination of COD by microwave atmospheric digestion was studied. The digestion time, the dosage of Ag2SO4

2、catalyst, the dosage of sulfuric acid, the mixed acid (H2SO4-H3PO4) ratio and different catalysts have an effect on the method for the determination of COD by microwave atmospheric digestion. Water samples of potassium h

3、ydrogen phthalate, glycine and glucose were chosen to be used with the determination of COD. The results are found that: （1） COD which potassium hydrogen phthalate and glucose samples were heated in 1 minute by microwave

4、 digestion coincided with that in 2 hours by heater according to international standard ISO 6060-1986. The recovery ratios were both 96%. The recovery ratio of glycine is 91% in 15 minutes by microwave digestion. Thus wh

5、en the digestion time was decreased in the spectrometric determination of COD by microwave atmospheric digestion, the result could be gained accurately. （2） Without Ag2SO4 by microwave digestion in 1 minute, the recovery

6、 ratio of potassium hydrogen phthalate and glucose were 97% and 96%, respectively. The result manifested that it was feasible without Ag2SO4 in the spectrometric determination of COD by microwave atmospheric digestion. B

7、ut without Ag2SO4 by microwave digestion in 15 minutes, the recovery ratio of glycine was 78%. The result illustrated that Ag2SO4 catalyst had an influence on the oxidation of samples. Therefore the spectrometric determi

8、nation of COD by microwave atmospheric digestion of easy oxidation samples could react without Ag2SO4. To determination about that of difficult oxidation, Ag2SO4 had to be added. （3） With the dosage of H2SO4 was decreas

9、ed in the reaction by microwave atmospheric digestion, the recovery ratio of potassium hydrogen phthalate was declined increasingly. So the reaction by microwave digestion is guaranteed to complete oxidation by acidity i

10、mportantly. （4） The ratio of mixed acid (H2SO4-H3PO4) which was 4:1 had a good result in the determination of COD by microwave atmospheric digestion as to potassium hydrogen phthalate. That was 100% in 1 minute. However