| 粉煤灰吸附-Fenton及热再生处理亚甲基蓝废水的特性研究 |
| 摘要点击 2256 全文点击 1429 投稿时间：2011-09-29 修订日期：2012-01-11 |
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| 中文关键词 粉煤灰 吸附 Fenton 热再生 亚甲基蓝 |
| 英文关键词 fly ash adsorption Fenton thermal regeneration methylene blue |
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| 中文摘要 |
| 首先表征了水洗粉煤灰(FA)及酸改性粉煤灰(M-FA)的物理化学特性,采用序批实验研究了FA及M-FA对亚甲基蓝(methylene blue, MB)废水的吸附特性,并对吸附平衡的粉煤灰进行了Fenton氧化再生和热再生性能研究.结果表明,FA和M-FA吸附速率方程符合二级吸附速率模型,吸附等温方程符合Langmuir等温模型,吸附平衡时间为30 min,FA和M-FA的平衡吸附量分别为4.22 mg·g-1和5.98 mg·g-1,M-FA吸附能力优于FA.在pH 2~12的范围内随着pH的提高,M-FA吸附量增大,FA吸附量缓慢减小至pH 8为最低点后明显增大,静电吸附对吸附量的增减起主要作用.当H2O2投加量为78.4 mmol·L-1、Fe2+投加量为0.72 mmol·L-1时,FA和M-FA的Fenton氧化法再生率分别为61%和55%.当热再生条件为400℃、 2 h时,连续3次的热再生,FA再生率增加,分别为102%、 104%和107%,M-FA再生率减小,分别为82%、 75%和74%.FA再生率优于M-FA,热再生优于Fenton氧化再生. |
| 英文摘要 |
| The physicochemical properties of water-washed fly ash (FA) and acid modified fly ash (M-FA) were investigated. The adsorption of methylene blue by FA and M-FA were studied by batch experiments. Two methods, Fenton-drive oxidation regeneration and thermal regeneration, were used for regeneration of the used FA and M-FA. The result showed that the rate of adsorption process followed the second order kinetics and the adsorption followed Langmuir isotherms.The adsorption equilibrium time was 30 min, and the equilibrium adsorption capacity of FA and M-FA were 4.22 mg·g-1 and 5.98 mg·g-1 respectively. The adsorption capability of M-FA was higher than that of FA. In the range of pH 2-12, the adsorption capacity of M-FA increased with the increase of pH, whereas the adsorption capacity of FA decreased slowly until the pH 8 and then increased. Electrostatic adsorption was the major factor on the adsorption capacity. Around 61% and 55% percentage regeneration(PR) were obtained for FA and M-FA respectively when 78.4 mmol·L-1 H2O2 and 0.72 mmol·L-1 Fe2+ were used. When the condition of thermal regeneration was 400℃ and 2 h, a positive correlation can be found between the PRs of FA and regeneration times, the PRs were 102%, 104% and 107% in three cycles of adsorption-thermal regeneration process. However a negative correlation can be found between the PRs of M-FA and regeneration times, the PRs were 82%, 75% and 74% in three cycles of adsorption-thermal regeneration process. The PR of FA was higher than that of M-FA, and thermal regeneration was superior to Fenton-drive regeneration. |
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