【作者】 覃强；

【导师】 陈孟林；

【作者基本信息】 广西师范大学 ， 化学工艺， 2008， 硕士

【摘要】 本文将高温气流氧化再生法引入凹凸棒石的再生,对吸附-高温气流氧化再生法处理染料废水进行了基础应用研究,主要的研究内容和得到的结论如下:1.对凹凸棒石吸附亚甲基蓝的吸附行为进行了研究。考察了凹凸棒石的粒度、吸附时间、染料溶液pH、染料溶液的初始浓度、温度对吸附的影响。在本实验中适宜的吸附条件为:吸附时间,2h;不需调节溶液pH;温度,室温。在所研究的温度和浓度范围内,用Langmuir方程能够很好地对吸附等温线进行拟合,吸附是一吸热的过程。20℃、30℃、40℃下饱和吸附量分别为76.92mg/g、84.03 mg/g、86.96 mg/g。动力学研究表明,吸附过程可用Lagergren一级速率方程描述,吸附过程主要是外扩散起作用。考察了动态吸附的流速对出水水质的影响,实验结果表明流速以小于5BV/h为好。2.采用高温气流氧化再生法再生吸附了亚甲基蓝的凹凸棒石,考察了再生温度、再生时间、空气流量等因素对再生效率的影响。温度越高,氧化分解掉的有机物越多,再生效率越高;流量越大,再生效率越高,当流量增至1.5L/min时,再生效率变化不大;随着再生时间的增加,再生效率不断增大,再生15min以上,再生效率变化不大。3.随着再生次数的增加,凹凸棒石的再生效率略有下降,从13次再生开始,再生效率趋于稳定。凹凸棒石性能稳定,可以反复使用。4.吸附在凹凸棒石上的亚甲基蓝在100℃以下失去结晶水,100℃-250℃裂解炭化,250℃以上被空气氧化并生成CO2、CO,330℃-630℃产生CH化合物,490℃左右含氮基团被氧化成NO。大于600℃下再生的整个过程产生了CO2、CO、NO2、NO、SO2、CH化合物等物质。500℃再生不彻底,600℃-700℃降解较完全。5.高温气流氧化再生的适宜工艺条件为:再生温度为600℃-700℃,再生时间为10min,空气流量为1L/min。更多还原

【Abstract】 In this paper, the method of High Gas-stream Oxidation was introduced to regenerate Palygorskite adsorbent. The basic application research about adsorption-High Gas-stream Oxidation to treat dye wastewater was studied. The main research content and results were as follows:1. Adsorption behavior of methylene blue on Palygorskite was studied. Effects of particle size, pH, initial concentration of the dye’s solution, temperature on adsorption are studied. The optimum adsorption conditions was composed of adsorption time 2h, initial pH and room temperature. A well fitted Langmuir equation was obtained for the adsorption isotherm within the observed temperature and the concentration of the dye’s solution range, indicating an endothermic adsorption. Saturated adsorption capacity were 76.92mg/g, 84.03 mg/g, 86.96 mg/g respectively at temperature of 20℃, 30℃, 40℃. The kinetic study showed that the adsorption process could be described by the first-order rate expression of Lagergren and was under the control of external diffusion diffusion. The effect of flow rate on effluent quality was studied, and the result showed that the flow rate should be less than 5BV/h.2. Palygorskite adsorbed methylene blue was regenerated by high gas-stream oxidation oxidation. Effects of temperature, reaction time and the air flow rate on regeneration efficiency were studied. The higher the temperature, the more organic compounds would be oxidized and the regeneration efficiency would be higher. The larger the air flow rate, the regeneration efficiency would be higher. When the air flow rate increased to 1.5L/min, the regeneration efficiency changed little. The longer the regeneration time, the regeneration efficiency would be higher. When Palygorskite adsorbed methylene blue was regenerated over 15minutes, the regeneration efficiency changed little.3. The more regeneration times, the regeneration efficiency would slightly descend. From the thirteenth regeneration, the regeneration efficiency tended to be stable. Palygorskite was repeatedly used with steady performance.4. Methylene blue absorbed by Palygorskite lost crystal water below 100℃. It was pyrolyzed and carbonized from 100℃to 250℃and was oxidized by oxygen and converted to CO2、CO above 250℃and hydrocarbon from 300℃to 630℃. Nitrogen containing group in Methylene blue was oxidized forming NO. The regeneration process produced CO2, CO, NO2, NO, SO2 and hydrocarbon above 600℃. The regeneration was not thorough at 500℃. Methylene blue was nearly degraded completely from 600℃to 700℃.5. The optimum regenerative conditions were as following: temperature was from 600℃to 700℃, the reaction time was 10min and the air flow rate was 1L/min.更多还原