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1.
凹凸棒石粘土沉降分散行为研究   总被引:5,自引:0,他引:5  
采用重力沉降分析法研究了酸碱度、表面活性剂、溶剂等对凹凸棒石粘土沉降分散行为的影响,并进行了理论分析.研究表明,溶液的pH、表面活性剂浓度和分散介质类别均影响凹凸棒石粘土的沉降分散行为;凹凸棒石粘土表面及介质的极性变化是凹凸棒石粘土沉降分散行为改变的重要因素.凹凸棒石粘土的沉降分散行为具有规律性:即溶液的酸碱电解质浓度越大,凹凸棒石粘土分散稳定性越好.分散介质的极性越大,凹凸棒石粘土的分散状况越好.表面活性剂能明显促进凹凸棒石粘土在低介电常数有机介质中的分散状况,高浓度的表面活性剂促进凹凸棒石粘土分散及其稳定性的增强.凹凸棒石粘土表面及介质的极性增大会使凹凸棒石粘土粒子间斥力增强,促进粒子破碎,改善粒子的粒径分布,同时使粒子在电斥力作用下分散稳定性增高。  相似文献   

2.
凹凸棒石粘土在废水处理中的应用   总被引:1,自引:0,他引:1  
凹凸棒石粘土是一种天然非金属粘土矿物,具有独特层链结构的晶质水合镁铝硅酸盐矿物,具有比表面积大,化学稳定性好,吸附能力强等特征.本文综述了凹凸棒石粘土在水处理中的应用,为以后研究开发提出了相应的意见和建议.  相似文献   

3.
苏皖凹凸棒石粘土研究现状和存在的问题   总被引:21,自引:3,他引:18  
在综合分析国内外凹凸棒石粘土研究成果的基础上 ,论述了苏皖凹凸棒石粘土研究的现状 ,详细阐述了凹凸棒石粘土研究存在的问题 ,提出研究纯凹凸棒石矿物的吸附性能、凹凸棒石吸附作用的机理、凹凸棒石物理化学性质和成因的关系、吸附实验方法和试验条件以及凹凸棒石成因机制的科学意义。文章首次提出了液相体系中凹凸棒石与蒙脱石互相作用的概念 ,同时讨论了认识和利用凹凸棒石与蒙脱石互相作用的科学理论意义及实际意义。  相似文献   

4.
凹凸棒石粘土动态法分离钍(Ⅳ)的研究   总被引:3,自引:0,他引:3  
研究了凹凸棒石粘土动态法吸附钍(IV)的酸度、吸附容量等性能,作出了吸附动力学曲线,并用动态法处理合钍废水,钍的吸附率99.8%。凹凸棒石粘土经用盐酸处理后可循环使用。并探讨了其吸附机理。  相似文献   

5.
盐酸活化纯凹凸棒石吸附Cr3+的性能研究   总被引:11,自引:0,他引:11  
凹凸棒石粘土的纯化对正确认识和理解凹凸棒石本身性质至关重要,文章从该粘土提纯入手,研究纯凹凸棒石矿物性质以及盐酸活化后的性质变化,并以Cr3+吸附为基础系统研究了纯凹凸棒石吸附水中重金属的性能.结果表明,5%盐酸活化凹凸棒石阳离子交换容量最大,为21.2 mmol/100 g; 30 ℃时5%盐酸活化凹凸棒石对Cr3+的等温吸附曲线同时符合Langmuir方程和BET方程.  相似文献   

6.
硫酸改性凹凸棒粘土的性能表征及吸附PbⅡ工艺研究   总被引:18,自引:1,他引:18  
研究了用不同浓度硫酸改性处理凹凸棒石粘土,并将其用于废水中Pb 的吸附处理,通过比表面测定探讨了凹凸棒粘土硫酸改性后比表面增加的原因.结果表明,4mol/L硫酸改性处理的凹凸棒粘土吸附能力最佳,在改性凹凸棒石粘土加入量为20~30g/L,水样pH=4~6,超声搅拌20min条件下,废水中Pb 的被吸附率接近99%.比表面积的增加归因于凹凸棒石中八面体不均匀、不连续溶解和局部四面体硅的溶蚀导致凹凸棒石孔道开放和直径扩大.  相似文献   

7.
有机凹凸棒石纳米微粒的制备及性能研究   总被引:3,自引:0,他引:3  
凹凸棒石粘土原矿经添加分散剂的机械搅拌、超声波处理、离心处理后得到提纯,提纯后样品被制备成纳米颗粒,利用十六烷基三甲基溴化铵对凹凸棒石粘土进行改性.测定了改性凹凸棒石的膨胀倍、ζ-电位,利用红外光谱和透射电镜进行了表征.结果表明,经过以上处理,有机改性剂与凹凸棒石发生作用,其性质和形貌都发生了变化:凹凸棒石疏水性增强,ζ-电位正值增大,有机凹凸棒石纳米微粒的长度为70~100nm,宽度为40~60nm,分散良好.利用改性凹凸棒石对造纸废水进行处理,当投加量为5g/L时,COD和色度去除率分别为86.7%和93.5%.  相似文献   

8.
煅烧凹凸棒石粘土对干粉砂浆性能的影响   总被引:2,自引:0,他引:2  
为了改善干粉砂浆性能,掺入占水泥质量20%的煅烧凹凸棒石粘土,研究其对干粉砂浆各项性能的影响.试验结果表明:在所研究的3种凹土中,以Z型煅烧凹土对砂浆稠度、保水性、抗压强度、粘结强度、收缩和抗渗性的改善效果最好;掺入450℃以下煅烧凹凸棒石粘土对砂浆强度、收缩和粘结强度没有显著改善;掺入高于450℃煅烧的凹凸棒石粘土,砂浆的抗压强度、粘结强度、收缩和抗渗性均有显著改善;掺入Z型凹土的砂浆28d抗压强度较空白砂浆提高了102.1%、粘结强度提高了39.7%、抗渗性能提高了25%.  相似文献   

9.
采用静态吸附实验方法,研究了吸附时间、溶液pH值、吸附剂投加量和溶液初始浓度等因素对凹凸棒石粘土吸附Sr2+、Cs+和Co2+的性能,并通过等温吸附模型拟合对其吸附过程及吸附机理进行了探讨。结果表明:凹凸棒石粘土对Sr2+、Cs+和Co2+的吸附效果依次为Co2+ > Cs+> Sr2;Freundlich和D-R等温吸附模型能较好地描述凹凸棒石粘土对Sr2+、Cs+和Co2+的吸附过程,其中,凹凸棒石粘土对Sr2+和Cs+的吸附以物理吸附为主,而凹凸棒石对Co2+的吸附过程以化学吸附为主,并且其吸附方式主要为离子交换的方式发生。  相似文献   

10.
通过对江苏、安徽两省凹凸棒石粘土成矿带坡缕石含矿层微量元素地球化学研究,探讨外生条件下,特别是形成凹凸棒石粘土的强碱性介质条件下微量元素的地球化学行为:即在低温条件下,它们的化学活泼性显著减弱;它们的赋存形式除与元素的离子半径,水合半径,水合能(K/mol)有关外,还与粘土矿物的晶体结构,矿物表面电化学性质,以及外生成矿地球化学环境密切有关.  相似文献   

11.
In the Southern Ocean, high accumulation rates of opal--which forms by precipitation from silica-bearing solutions--have been found in the sediment in spite of low production rates of biogenic silica and carbon in the overlying surface waters. This so-called 'opal paradox' is generally attributed to a higher efficiency of opal preservation in the Southern Ocean than elsewhere. Here we report biogenic silica production rates, opal rain rates in the water column and opal sediment burial rates for the Indian Ocean sector of the Southern Ocean, which show that the assumed opal paradox is a result of underestimated opal production rates and overestimated opal accumulation rates. Our data thus demonstrate that the overall preservation efficiency of biogenic opal in this region is substantially lower than previously thought, and that it lies within a factor of two of the global mean. The comparison of our revised opal preservation efficiencies for the Southern Ocean with existing values from the equatorial Pacific Ocean and the North Atlantic Ocean shows that spatial differences in preservation efficiencies are not the primary reason for the differences in sedimentary opal accumulation. The reconciliation of surface production rates and sedimentary accumulation rates may enable the use of biogenic opal in the reconstruction of palaeo-productivity when the factors that affect the Si/C ratio are better understood.  相似文献   

12.
本文讨论了华东某地蛋白石的成分、物理性质、组构和成因机制等。并同已知蛋白石资料进行了对比。  相似文献   

13.
应用X射线衍射定量分析方法中的基体清洗法及其演化而来的自清洗法对粘土中常见矿物蒙脱石、绿泥石、高岭石、伊利石、长石、方解石、白云石、赤铁矿、蛋白石的K值进行了实验测定。在此基础上提出了采用稀释法,即外加一定量石英对由于粘土矿物结晶度和定向度差异所引起定量分析偏差进行修正的方法。  相似文献   

14.
Monodisperse silica spheres of 252 nm with a standard deviation of 5.7% are prepared by Stber method. By compari-son of both of media, ethanol instead of water is used to assemble opal, and the artiflcial opal has been prepared by the sedimentation inethanol of silica spheres. The structure of the opal prepared has been examined and discussed. The results show that the artificial opal hasa structure similar to the face-centered cubic (fcc) type packed system with silica spheres. Transmission measurements of the artificial opalhave been conducted, which shows that the artificial opal is quasi-full band gap silica photonic crystals in the visible region.  相似文献   

15.
The possibility of modified opal as the stabilizer of hydrogen peroxide bleaching was investigated. The results showed that the modified opal in place of sodium silicate as the stabilizer of hydrogen peroxide bleaching is feasible. At the same dosage, above 3% ISO can be increased for both wheat straw pulp and deinked pulp. The stabilizing ability of the modified opal to hydrogen peroxide bleaching of pulp is improved markedly. It is favorable for bleaching to increase temperature and time within a permissive extent. The suitable process conditions are 10% of pulp consistency, 3% of hydrogen peroxide, 1.5% of sodium hydroxide, 3% of the modified opal, 70℃ and 60 min when the modified opal is used as the stabilizer of hydrogen peroxide bleaching. At these conditions, the brightness gain can reach about 16% ISO for wheat straw pulp. In addition, it is favorable for bleaching to add a little magnesium sulfate when the modified opal is used as the stabilizer of hydrogen peroxide bleaching, the brightness of pulp can increase I%ISO if0.05% of magnesium sulfate is added. The cost analysis indicated that the modified opal is superior to sodium silicate as the stabilizer of hydrogen peroxide bleaching in economical aspect and has further the potential of market development.  相似文献   

16.
在辽东湾、渤海湾及其邻近的冀东油田和大港油田东部的钻遇地层中存在易塌的火山岩地层。为了探寻适用于该地层的防塌措施 ,对冀东油田M2 7- 2 7井岩心的岩石结构、矿物组成、水分含量、线膨胀率、回收率和稳定指数等进行了分析。结果表明 ,该套岩层含有大量蛋白石等粘土矿物 ,且非均质性严重 ,成分复杂 ,裂隙发育。因此 ,在钻进过程中 ,该井段的钻井液需要有强抑制、强封堵、低失水的性能。基于这一认识 ,优选出了多元醇防塌钻井液。现场试验结果表明 ,该钻井液体系有效地保证了玄武岩井段的安全顺利钻进及井眼规则性。  相似文献   

17.
Opal hydrogels could be synthesized with polymer inverse opal template. A pH responsive opal N-iso-propylacrylamide/acrylic acid copolymerized hydrogel was prepared as an example. The ordered structure and response to pH were investigated. Through the sol-gel process of tetrabutyl titanate, opal titania was obtained with the opal hydrogel template.  相似文献   

18.
提出一种新的骨料碱活性检测方法——溶胶-凝胶膨胀法,并用其对蛋白石和天然骨料的碱活性进行了研究,试验结果表明,利用溶胶-凝胶膨胀法,蛋白石表现出明显的碱活性,并且发现在蛋白石掺量为最劣点时的溶液中SiO2含量和SiO2/Na2O摩尔比都达到最值,膨胀量也达到最值。  相似文献   

19.
利用毛细管辅助沉积方法制备了厚度及膜内裂缝的形状、分布可控的三维蛋白石薄膜。讨论了所得薄膜光学性质以及膜的形态特性与薄膜厚度之间的关系。用同样的方法制备了由不同粒径的球体基元晶体带构成的横向交替异质结构。  相似文献   

20.
The correlation of opal content and MAR with oxygen isotopic records of benthonic foraminifera at Site 1143, southern South China Sea indicates that,since about 900 ka,the increasing opal content and MAR during the interglacial periods is inferred to reflect the bigher surface productivity ,for the intensified summer monsoon during the interglacial periods would result in the enhanced upwelling and nutrient supply,Time-sequence spectral analyses of oxygen isotopic record ,opal content and MAR at intervals of 0-900 ka reveal that the changes of surface productivity were dominantly forced by the variations of the earth orbital cycles.  相似文献   

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