用高纯膨润土制备无机凝胶的工艺研究

以莱西钙基膨润土为原料,经二次湿法提纯-2μm的膨润土,钠化改型,制备了高纯度的钠基膨润土,在此基础上,探索了无机凝胶的制备工艺,考察了不同磷化剂和胶化剂对无机凝胶的影响。提出了以0.7%焦磷酸钠为磷化改性剂,1.5%CaO为胶化剂制备无机凝胶的新工艺。希望能代替进口的VEEGUM系列应用于日化工业。     

高放废物处置库预选缓冲/回填材料液塑限测定试验研究

深地质处置被国际上公认为处置高放废物的最有效可行的办法。缓冲/回填材料是高放废物深地质处置中非常重要的一道人工屏障。经过筛选,内蒙古高庙子钠基膨润土被确定为我国高放废物深地质处置的首选基料。通过对该钠基膨润土的落锥式和碟振动式两种液塑限测定方法的比较,确定利用碟振动式仪法测试更合理,测得液限为310%,塑限值为39.0%,塑性指数为271.0%。结果表明,内蒙古高庙子钠基膨润土具有高的水容量、荷重下的高致密性、低渗透性、较高的强度和较强的水稳定性。     

振荡时间、离子强度、温度和pH值对GMZ膨润土中Cr（Ⅲ解）吸特性的影响

对吸附在高庙子（GMZ）膨润土上的Cr（III）进行解吸实验,研究振荡时间、解吸溶液离子强度、温度和pH值等因素对解吸特性的影响规律。结果表明：高庙子膨润土上Cr（III）的解吸过程较易发生;Cr（III）的解吸动力学过程较吸附过程慢,实验条件下解吸过程在3 h后达到平衡;当使用0.1 mol/L HCl、1 mol/L NaCl和1 mol/L CaCl 2作为解吸液时,Cr（III）的最终解吸率分别达89.4%,56.5%和77.2%;增大解吸溶液的离子浓度能够促进解吸过程的发生;pH值对Cr（III）解吸过程有重要影响;吸附/解吸过程较符合Freundlich等温模型。GMZ膨润土在处理Cr（III）废水时具有较好的再生能力,可以多次重复利用。     

Some properties and potential applications of the Na- and Ca-bentonites of ordu (N.E. Turkey)

Ca- and Na-bentonites formed throughout the Eastern Black Sea were distinguished on the basis of their mineralogical, chemical, and physical properties. The properties of the Na- and Ca-bentonites were studied using X-ray diffraction, chemical analyses and a series of physical testing methods. Montmorillonite is the major mineral in both bentonites. Except for montmorillonite, the Ca-bentonites (CAB) contain opal-CT, minor amounts of quartz, feldspar and biotite, and (rarely) pyrite and calcite. The Na-bentonites (NAB) contain smectite (montmorillonite) and small amounts of opal-CT, quartz, and feldspar. In the natural state, the chemical and physical properties including cation exchange capacity, viscosity, swelling index, gelling strength and pH of the NAB are higher than the CAB. Surface area and brightness of the CAB are unusually high compared to the NAB. Their bleaching properties are generally similar. The specific surface area and filtration loss of CAB are higher than in NAB. The natural bentonites could be used in paper coating and filling, paint, pharmaceuticals, and as cosmetics and filtering agents after the removal of non-clay minerals and after making some processes/modifications.     

Coupled effects of saline solutions and temperature on the swelling deformation property of GMZ bentonite-sand mixtures

Based on the results of one-dimensional free swelling tests, the coupled effects of NaCl-Na₂SO₄ solutions and temperature on the swelling deformation property of compacted GMZ bentonite-sand mixtures were analyzed. The concentrations of the NaCl-Na₂SO₄ solutions were 0, 0.008, 0.04, 0.08 and 0.16 mol/L, the temperatures were 20 °C, 40 °C, 60 °C, 80 °C and 90 °C and the sand contents were 0, 30 and 50%. X-ray diffraction (XRD) and mercury intrusion porosimetry (MIP) tests were also performed to find the influences of the temperature, solution concentration and sand content on the mineral composition and microstructure. The results showed that the maximum swelling strain of the specimens increased with an elevated temperature, while it decreased with increases in the solution concentration and sand content. The swelling process was accelerated by the rising temperature. The XRD tests indicated that the combined effect of a high temperature and a high solution concentration may have caused more Na⁺ from the saline solutions to enter the interlayer, partly displacing the divalent cations. The MIP tests demonstrated that adding sand to the bentonite could reduce the amount of inter-granular pores and increase the intra-aggregate pores. These findings are advantageous to the transfer of heat and pour fluid in the specimens; and thus, the swelling deformation capacity of the bentonite-sand mixtures was higher than that of pure bentonite under the same conditions.     

高庙子膨润土与北山地下水的长期作用试验

以内蒙古兴和县高庙子钠基膨润土和甘肃北山BS05号钻孔地下水为研究对象,依托低氧手套箱,在常温低氧条件下开展膨润土与地下水长期作用试验研究,获得了1年内膨润土 北山地下水体系pH和Eh值随时间的变化特征;得到了作用前后体系液相关键离子成分以及固相可交换阳离子、化学成分,依托拉曼光谱仪测定了作用前后膨润土的结构。结果表明,膨润土 北山地下水体系在本试验条件和时间范围内可以保持相对稳定的状态。     

高庙子膨润土及其混合材料导热性能研究

导热性能是高放废物地质处置库缓冲/回填材料的重要性能之一。采用瞬变平面热源法,研究了我国高放废物地质处置首选缓冲/回填材料高庙子膨润土,及以其为主料,添加不同含量石英砂、北山花岗岩碎屑组成的混合材料的导热性能。分析了添加剂种类和含量、干密度、饱和度等因素对导热系数的影响。研究结果表明:高庙子膨润土及其混合材料的导热系数、热扩散系数都随干密度和含水量的增大而增大;石英砂、北山花岗岩碎屑能够不同程度提高膨润土的导热系数,石英砂的作用优于北山花岗岩碎屑;饱和度对添加剂发挥其提高缓冲/回填材料导热性能的作用影响明显,饱和度越高,添加剂的作用越显著。     

高庙子膨润土矿勘探与钠基膨润土开采

高庙子膨润土矿是我国高放废物地质处置库缓冲回填材料首选供应基地,国内对高庙子钠基膨润土进行了大量试验研究和理论分析。随着研究工作的深入,需开采天然钠基土样品以满足试验需求。通过施工3个勘探孔,发现主矿区8~24勘探线的膨润土矿石质量好,层位稳定,与已掌握的资料相符。对比两个拟开采位置的矿石质量、矿层厚度、开采条件等,确定使用露天剥离的方式开采膨润土样品,并对开采出的矿石进行初步加工提纯,完成了开采未来5~10年缓冲回填材料试验研究所需样品的任务。     

钠基膨润土对硅溶胶涂料悬浮性的影响

硅溶胶涂料以其良好的工艺性能在熔模铸造领域得到越来越广泛的应用，但在实际使用过程中该涂料也存在着悬浮性不良等问题，影响到涂料实际使用。分析了改善硅溶胶涂料悬浮性的机理，以及硅溶胶涂料悬浮性与流杯粘度及涂片厚度等工艺性能之间的关系。采用钠基膨润土改善硅溶胶涂料的悬浮性，并取得了良好效果。