【作者】 杜晓伟；

【导师】 朱南文；

【作者基本信息】 上海交通大学 ， 环境科学与工程， 2013， 硕士

【摘要】 焚烧是污泥处置的主要处置方式之一，而焚烧灰渣的后续综合利用是实现污泥安全处置的重要保证。污泥焚烧灰富含硅铝元素，适宜作为沸石合成的原料，因此利用污泥焚烧灰合成沸石可实现其高值利用。基于此，本文开展以污泥焚烧灰为原料合成NaSOD型沸石的研究，采用X射线衍射仪、扫描电子显微镜、傅里叶红外光谱仪、BET比表面积和孔隙率分析仪以及综合物性测量系统等对合成产物进行了表征，并结合亚甲基蓝吸附实验，考察其吸附性能。主要结果如下：（1）采用常压开放合成体系，依次进行了酸溶除杂、碱熔融活化和NaSOD型沸石水热合成的研究，探讨了预处理条件以及晶化条件对沸石合成影响。在现有测试条件下，酸溶除杂预处理最适宜pH为1；碱熔融活化预处理最适宜温度为700℃；NaSOD型沸石的最佳晶化条件组合为：n（SiO₂）/n（Al₂O₃）为2、碱度比1.5、晶化温度100℃、晶化时间10h。SEM结果显示：合成NaSOD型沸石晶型单一，结晶度好，晶粒大小均匀，晶体呈完整的球形花瓣状，且具有很好的分散性；BET比表面积达222m₂.g^-1，阳离子交换容量达80.35mmol·（100g）^-1；同时，NaSOD型沸石中含有的Fe元素，使其具有良好的超顺磁性。（2）NaSOD型沸石对亚甲基蓝吸附性能显示：其平衡吸附时间为360min；染料的平衡吸附量随初始pH的升高而增大，在亚甲基蓝初始浓度为51.2mg·L^-1，初始pH2.04⁹.16之间，平衡吸附量在pH9.16时达到最大，为23.7mg·g^-1，零电荷点左右，平衡吸附量的增速最大；随着沸石投加量的增加，去除率增大，但其平衡吸附量从43.9mg·g^-1减少到16.2mg·g^-1；同时，考察了不同离子强度对于沸石吸附性能的影响，发现阳离子会与MB⁺竞争沸石表面带负电荷的吸附位，从而降低沸石对染料的平衡吸附量，且Ca²⁺的影响大于Na⁺和K⁺。（3）吸附等温线模拟显示，NaSOD型沸石对亚甲基蓝的吸附符合Langmuir非线性拟合，说明吸附是均匀的单层吸附。动力学拟合结果表明，吸附符合准二级动力学模型。颗粒内扩散模型研究结果显示，吸附过程是由颗粒内扩散和膜扩散联合控制的。热力学参数的计算结果表明：吸附过程中含物理吸附和化学吸附，且化学吸附占主导作用；吸附为吸热过程，且是自发的。（4）吸附机理探讨表明，NaSOD型沸石对亚甲基蓝的吸附主要有四种作用：静电引力、氢键作用、n-π共轭作用以及范德华力。其中静电引力和氢键作用是主要的。更多还原

【Abstract】 As incineration becoming more widely used as a method of sewagesludge treatment, bottom ash from sludge incineration plant increasedgreatly and the synthesis of zeolite is one of the promising ways for theutilization of sludge bottom ash according to its chemical components. Inthis work, the potential synthese process were proposed, and thesynthesized NaSOD zeolite was characterized by X-ray diffraction,scanning electron microscopy, Fourier transform infrared spectroscopy,and BET. The adsopriton property was also tested based on the methyleneblue （MB） experiments. The main results were as follows:（1） An open system with ordinary pressure was used for thesynthesization of NaSOD zeolite. Bottom ash should be activated byacid-soluble impurity and alkali-molten activation subsequently. Theoptimum pH of acid-soluble impurity pretreatment was pH1, and theright temperature of alkali-molten activation was700℃under the testedconditions. It was also found that the best combination of NaSOD zeolitecrystallization was: n（SiO₂）/n（Al₂O₃）2, with the alkalinity ratio1.5, thecrystallization temperature100℃, and the crystallization time10h.Synthesized product was pure NaSOD type zeolite with a highcrystallinity and uniform size. The crystal was complete sphericalpetaloid and has a good dispersibility, with a BET specific surface area of222m²·g^-1and cationic exchange capacity of80.35mmol·（100g）^-1. Thepresent of Fe in the sludge bottom ash results in a goodsuperparamagnetic in the synthesization of NaSOD zeolite.（2） The adsorption properties of synthesized zeolite were tested bythe MB adsorption experiment. Effect of adsorption time, initial pH, zeolite dosage and ionic strength on the adsorption property wasdiscussed, and it was found that the equilibrium adsorption capacity ofthe zeolite increased as pH value increase from2.04to9.16under theequilibrium adsorption time of360mins, and the the maximumequilibrium adsorption capacity reached to23.7mg·g^-1. The biggestgrowth rate of adsorption among was found around the zero point ofcharge. The removal rate of MB increased as the zeolite dosage/MBincreased, while the equilibrium adsorption capacity decreased, since thecation will occupy the adsorption sites of zeolite, and thus reduce the thezeolite equilibrium adsorption amount of MB⁺, and Ca²⁺has greatereffects than that of Na⁺and K⁺.（3）The adsorption process of MB by NaSOD zeolite fits theLangmuir non-linear adsorption fitting greatly; kinetic research showedthat the adsorption was in line with quasi-second-order kinetic model;results of the intraparticle diffusion model showed that the adsorptionprocess was jointly controlled by particle diffusion and film diffusion; theadsorption process was endothermic and spontaneous, and predominatedby the physical and chemical adsorption according to the thermodynamicparameters results.（4） Electrostatic attraction and hydrogen bonding might be the twomain forces for the adsorption of MB, although both of n-π conjugate andvan der Waals forces also contributed to them.更多还原