【作者】 水远敏；

【导师】 姚宏；

【作者基本信息】 北京交通大学 ， 市政工程， 2009， 硕士

【摘要】 本文选取了活性炭、木炭和两种改性污泥共四种吸附剂吸附直接大红染料废水,分别用电镜观察了SEM图,测定了其激光粒度和Zeta电位、用差热分析仪测定了其热稳定性、同时进行了FTIR红外光谱分析,研究了四种吸附剂对直接大红模拟染料废水的吸附效果,实验结果表明:(1)四种吸附剂含有丰富的孔结构,差热分析证实,四种吸附剂热稳定性强弱顺序为:改性污泥B＞活性炭＞改性污泥A＞木炭,红外光谱图显示吸附剂官能团组成较为简单,主要为缔合-OH,C=O和C=C,C-O-C和C-C。(2)吸附时间、温度、离子强度对吸附过程均存在一定的影响。(3)常温下活性炭、木炭、改性污泥A、改性污泥B吸附平衡时间分别为:24h,1h,24h,48h;四种吸附剂吸附能力强弱顺序为:活性炭＞改性污泥B＞改性污泥A＞木炭,其常温下对染料的去除率分别为:82.3%,70.5%,42.7%,40.4%。(4)吸附过程可以用Langmuir和Freundlich等温吸附方程进行描述。对于活性炭、改性污泥A,改性污泥B温度升高有利于吸附的进行,吸附过程为吸热反应;而木炭则随着温度的升高吸附能力减弱,吸附过程为放热反应。在温度为25℃时,活性炭、木炭、改性污泥A、改性污泥B的最大吸附量分别为357.14mg·g-1、31.847 mg·g-1、97.087 mg·g-1,142.86 mg·g-1。(5)离子强度的引入对活性炭吸附直接大红有促进作用,而对其他三种吸附剂的吸附有抑制作用。(6)根据温度对吸附的影响计算了四种吸附剂对直接大红染料的表观吉布斯自由能变化、焓变以及熵变,结果表明四种吸附剂对染料吸附的表观吉布斯自由能ΔG~0的值均小于0,吸附是自发进行的,其中活性炭、改性污泥A、改性污泥B的吸附是吸热反应,熵增大的过程,木炭对染料的吸附是放热过程,熵减小的过程。(7)根据其时间对吸附效果的影响数据由计算结果得到四种吸附剂对大红染料的吸附过程均符合二级吸附动力学模型。(8)改性污泥作为一种以废治废的廉价吸附剂,可以有效地处理染料废水。更多还原

【Abstract】 In this paper,the active carbon sorbent,charcoal sorbent,two different modified sludge sorbent were used for treating dye wastewater,the strcture of the four soebents was characterized by Scanning Electron Microscope and infrared spectroscopy,tested for granularity distributing and ZETA potenlial,the thermal stability was mensurated by differental thermal analysis apparatus The results show that:(1) Four kinds of sorbents have abundant pores.The results from DSC indicate that four absorbents have thermal stability,The order of the thermal stability of the four adsorbents are as follows:modified sludge B＞active carbon＞modified sludge A＞charcoal;the results form FTIR indicate that the functional groups which in the sorbents are simpleness,association-OH,C=O,C=C,C-O-C and C-C.(2) The adsorption time,the adsorption temprature,the salinity to adsorb have certain influence to the adsorption effects.(3) The equilibrium time in normal temperature of the four adsorbents are as follows:24h,1h,24h,48h.The order of the capability of the four adsorbents for direct scarlet was as follows:active carbon＞modified sludge B＞modified sludge A＞charcoal,the corresponding elimination rate in room temperature was 82.3%,70.5%, 42.7%,40.4%.(4) The adsorption process all fit the Langmuir and the Freundich isothermmodel exellently.For active carbon,modified sludge A and modified sludge B,the increase of temperatur does favor the adsorption process,while charcoal is in the other way round. when the temperatur is 25,the maximum adsorption capacities of active carbon,charcoal,modified sludge A and modified sludge B are 357.14mg·g-1,31.847 mg·g-1,97.087 mg·g-1,142.86 mg·g-1,respectively.(5) For active carbon the existence of salinity has certain stimulation effect to adsorption,and has inhibitory effect for the other three.(6) According to the influence of the temperature to the adsorption,the change of apparent Gibbs free energy,the enthalpy as well as the entropy of four kinds of adsorbents to direct scarlet are calculated.The results indicated that the adsorption processes of four kinds adsorbents are spontaneous.Active carbon,the adsorption process of modified sludge A and modified sludge B are endothermic and entropy increased process,while charcoal is exothermic and entropy reduced reaction. (7) The influence of adsorption time to the adsorption shows that the adsorption process of all the adsorbents conform to the second-order model.(8) The modified sludge as a inexpensive absorbent may disposal the priting waste water effectively.更多还原