【作者】 王辉；

【导师】 关毅；

【作者基本信息】 天津大学 ， 工业催化， 2006， 硕士

【摘要】 凹凸棒石是一种具有链层状结构的晶质水合镁铝硅酸盐粘土矿物,在我国储量约占世界总储量的一半以上。凹凸棒石具有大表面、强吸附性等特点,常被研究用做处理污水的吸附剂,并取得较好效果。凹凸棒石矿物中经常伴生石英和白云石等杂质,其中石英是脊性物质,不易成型,且比表面积小,它的存在会影响制备出的凹凸棒石颗粒的机械强度、耐水性和吸附性等。本研究利用机械搅拌水沉降分离、添加分散剂超声波等方法对凹凸棒石进行提纯实验,结果表明使用硅酸钠分散剂可获得较好的提纯效果。制备载体实验是以干混或湿混方式在已提纯的凹凸棒石中加入膨润土、碳酸钠、氯化铝、硫酸锰等添加剂,后经研磨、压片、干燥、煅烧等制备出载体。再利用热分析、X光衍射、比表面、红外测定等手段,分析凹凸棒石和添加剂混合方式、添加剂加入量、煅烧温度和时间对凹凸棒石的结构和性能的影响。通过实验测得制成的凹凸棒石载体散失率以及微生物固定化效果,最终确定适宜的添加剂用量、混合方式、煅烧温度和煅烧时间为:凹凸棒石:膨润土:Na₂CO₃:AlCl₃:MnSO₄=100:10:1.5:1:1.5,湿混方式混合,煅烧温度为450℃,煅烧时间为1小时。采用先吸附法固定化,再戊二醛交联的复合固定化方法,将复合菌群固定化在用凹凸棒石制备的载体上。通过测量细胞干重和固定化载体上微生物活性来检验固定化效果,并与游离菌群进行比较,实测数据说明固定化在凹凸棒石载体的菌群可以满足处理实际废水的要求。更多还原

【Abstract】 Atapulgite is crystal hydrated magnesium aluminum silicate with a unique chain layer structure. It is so plentiful that the quantity is above half of the world in our country. It has excellent absorptive property which attracts many scholars studying and acquiring good effects as wastewater treatment adsorbents. There are some quartzes and dolomites in attapulgite, quartz has small specific surface area and it is difficult to molding. It will influence mechanical intensity, adsorptive property and resist water property of attapulgite granules with so many quartzes.We purify the attapulgite with two methods: Mechanical mix round purification with water and ultrasonic purification with sodium silicate dispersant, and it is found that the method purification with sodium silicate dispersant is better.The experiments for preparing carrier is to put montmorillonite, sodium carbonate, aluminum chloride and manganese sulfate into purified attapulgite by dry mixed way or wet mixed way, and then to dry and to calcine etc. The influence of mixed ways, mass and proportion of additives, calcined temperature and time for attapulgite’s structure and capability is analyzed by TG-DTA, XRD, TEM and FT-IR etc. The conditions for preparing the attapulgite carrier are ascertained by testing dispersed ratio and immobilized effect. It is found that the best conditions of chemical additive are these: attapulgite: montmorillonite: Na₂CO₃: AlCl₃: MnSO₄ =100:10:1.5:1:1.5, and the calcined temperature is 450℃, and the calcined time of is 1h.Complex strains are immobilized on attapulgite carriers. It is used complex methods: First they are immobilized by adsorption, second joined together with glutaraldehyde. The effect of immobilized granules is tested by measuring the weight of dry immobilized cells and the activeness, and compared with dissociative cells. It is found that the effect of immobilized cells is better than dissociative cells.更多还原