| 粉煤灰催化H2O2氧化水中对硝基酚研究 |
| 摘要点击 1851 全文点击 945 投稿时间：2008-08-07 修订日期：2008-12-15 |
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| 中文关键词 粉煤灰 催化 H2O2 对硝基苯酚 |
| 英文关键词 fly ash catalytic oxidation hydrogen peroxide P-nitro phenol(PNP) |
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| 中文摘要 |
| 采用粉煤灰做催化剂，研究了在常温常压下对H2O2氧化对硝基酚（PNP）的催化性能.在分析粉煤灰理化性质的基础上，考察了粉煤灰种类，不同预处理方法以及粉煤灰投加量、pH、反应时间、H2O2浓度等因素对PNP去除率的影响.结果表明，比表面积大，未燃炭含量高的粉煤灰催化效果好；经过350℃预处理可以有效提高其催化性能；在pH=2，反应时间为60 min, H2O2起始浓度为200 mg/L, 粉煤灰投加量为60 g/L的条件下，热处理粉煤灰对PNP的去除率为62.38%.其中，粉煤灰的比表面积、未燃炭以及活性金属氧化物均是影响其催化活性的重要因素.在催化氧化对硝基苯酚过程中，吸附占有重要作用，为总去除率的65.97%.粉煤灰可以重复使用，随使用次数增加，粉煤灰催化性能提高.第2次、第3次对PNP的去除率分别为82.47%和98.72%，之后的9次实验中去除率均保持在99%左右，在使用12次后催化性能降低. |
| 英文摘要 |
| Fly ash was investigated as a catalyst in the oxidation of P-nitro phenol (PNP) with H2O2 at ambient temperature and pressure. The physical and chemical properties of fly ash were analyzed. The effects of fly ash composition, pretreatment methods and other parameters (such as dosage, pH, reaction time and oxidant concentration) on PNP removal rate were studied. It was found that fly ash with larger specific surface area and higher carbon content demonstrated higher catalytic activity. Heat treatment (350℃) on fly ash could effectively improve the PNP removal rate. With an initial H2O2 concentration of 200 mg/L, 60 g/L heat-treated fly ash could remove 62.38% PNP at 25℃, pH=2. Specific surface area, carbon and metal oxide contents of fly ash play an important role in the catalysis process. The adsorption control experiment showed that adsorption was the main effect (65.97%) in the catalysis process. The activity of the catalyst gradually increased during its reuse. The PNP removal rate could reach 82.47% and 98.72% in the second and third rounds of reuse, respectively. The removal rate remained at about 99% in the rest 9 rounds of reuse. And the catalytic properties decreased after 12 times uses. |
