氧化钙改性粉煤灰对酸性橙的吸附脱色性能试验研究

Study on the Adsorption of Acid Orange by Fly Ash Modified with Calcium Oxide

本文选择氧化钙为改性剂对粉煤灰进行改性试验,研究其对酸性橙染料的吸附脱色性能,结果表明:氧化钙和粉煤灰的质量比为1∶8、灼烧温度为400℃、不调节pH值、改性灰的投加量为14 g/L时,对浓度为25 mg/L酸性橙的脱色率可达95.5%,且碱性条件有利于吸附反应的发生;粉煤灰对酸性橙的吸附可用Langmuir吸附等温模式进行描述;通过对原灰和改性粉煤灰进行的比表面积测定和扫描电镜表征分析可知,氧化钙的加入并没有改变粉煤灰的基本形状,只是增大了粉煤灰的比表面积,从而提高了其吸附性能。

Calcium oxide（CaO） is chosen to modify fly ash and the adsorption performance of acid orange by modified fly ash（MFA） is investigated.It is founded that the decolorization rate of acid orange is 95.5% under the conditions of 1/8 mass ratio of fly ash to CaO,14 g/L dosage of MFA,400℃ temperature and unadjusted pH.Higher pH value favors the adsorption.The adsorption behaviors of modified fly ash to acid orange correspond with Langmuir model well.In addition,FA and MFA are examined in specific surface area and analyzed by scanning electron microscope（SEM）.Results show that the structure and shape of FA are not changed by adding CaO,with the exception of an increased specific surface area which improves the adsorptive capability.