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81.
Yuanpeng Fu Weining Xie Jie Wang Xuejie Bai Jinlong Li 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(14):1663-1673
The strong hydrophilic properties of both sub-bituminous coal and kaolinite make it difficult to separate by direct flotation. In this paper, the removal of kaolinite from fine sub-bituminous coal was investigated by reverse flotation tests using N, N-dimethyl dodecyl amine (DRN12) as a kaolinite collector. In addition, the adsorption behavior of DRN12 on coal and kaolinite surfaces was also studied to explore its interaction mechanism The experimental results showed that the beneficiation of kaolinite from the raw coal was effective only in the acid pulp with DRN12 less than 1.5kg/t. Moreover, in acid solutions, DRN12 preferentially adsorbs on kaolinite surface by electrostatic force, and the adsorption capacity of DRN12 on kaolinite surface was much higher than on coal, which caused an increase of kaolinite hydrophobicity and floatability. 相似文献
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83.
In this study, polyindole (PIN) and polyindole/kaolinite (PIN/KAO) composite were synthesized by free radical polymerization using FeCl3 as an initiator. Average particle sizes (d50) of PIN and PIN/KAO composite were determined by dynamic light scattering (DLS) as 7.2 and 6.2 μm, respectively. The samples were characterized by FTIR, elemental analysis, DSC/TGA and SEM measurements. Suspensions of KAO, PIN, and PIN/KAO composite were prepared in silicone oil (SO) and the sedimentation stabilities were determined. Electrorheological (ER) properties of these suspensions were studied as a function of dispersed phase concentration, shear rate, shear stress, and temperature; and yield stresses and excess shear stresses determined. Further, dielectric properties of KAO, PIN, and PIN/KAO composite were investigated. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
84.
煤系高岭土二次煅烧水热合成P型分子筛 总被引:6,自引:0,他引:6
以煤系高岭土为原料,采用二次煅烧和水热合成的方法制备了P型分子筛.第一次煅烧的条件是高岭土和氯化铵混合,条件是800℃、2 h,得到含有少量铁离子的偏高岭土;第二步煅烧的条件是向偏高岭土中加入碱,煅烧条件是40℃,2 h.通过单因素实验,考察了SiO2/A12O3、老化时间对晶相的影响,H2O/Na2O对晶化时间的影响,配料煅烧对产率、粒径、Ca2 、Mg2 交换量的影响.确定了反应的最佳条件为:以NaOH作为配料进行二次煅烧,SiO2/A12O3=3,H2O/Na2O=45,无老化步骤.用XRD对产品进行了表征,用化学滴定的方法确定了所合成P型分子筛的Ca2 、Mg2 交换量,结果表明:P型分子筛结晶完好,钙镁离子交换容量大. 相似文献
85.
Two freeze-dried poly(hydroxo aluminum) intercalated Wyoming bentonites were prepared starting from two different aluminum pillaring solutions. Their charge versus pH properties were studied by zeta potential measurements, potentiometric titrations and calcium sorption measurements in order to determine the speciation of the intercalated Al-species as a function of pH. The structural changes of the intercalated bentonite induced by the pH increase were studied by XRD analysis and N2 adsorption/desorption measurements. At pH 5 the permanent charge (0.75 meq/g) of the original Wyoming bentonite is completely neutralized by positively charged Al-hydroxo species. With increasing pH the Al-species deprotonate and aggregate until their complete neutralization at pH 9.4. Above this pH the Al-polymers start to dissolve from the clay as Al(OH)4−. 相似文献
86.
The determination of the electrokinetic potential of clay is very important in many applications. Therefore, this work was aimed at studying the effect of poly(4‐ sodium styrene sulfonate) on the electrokinetic potential and the sedimentation behavior of kaolinite clays at different pH values and/or in the presence of sodium or calcium chlorides. At pH values lower than the point of zero charge (PZC) of the kaolinite clay, the zeta potential of Na‐ or Ca‐kaolinite in CaCl2 solutions was higher than that in NaCl solutions at the same concentration. Above the PZC, the zeta potential of Na‐ or Ca‐kaolinite in NaCl solution was higher than that in CaCl2 at the same electrolyte concentration. These results reflect the ability of calcium cations to compress the double layer of the kaolinite clay better than sodium cations. Also, below the PZC and at low concentrations of poly(4‐sodium styrene sulfonate), the zeta potential of the kaolinite clay suspensions had low value, while the sediment volumes had higher values. On the other hand, above the PZC at increasing polymer concentrations, the zeta potentials increased but the sediment volumes had lower values compared to those produced below the PZC. The data showed the zeta potential of Na‐kaolinite suspensions are higher than Ca‐kaolinite, producing lower sediment volumes of Na‐kaolinite compared to Ca‐kaolinite at the same concentrations of polymer and/or pHs. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1705–1711, 2006 相似文献
87.
运用扫描电镜SEM、透射电镜TEM、X-射线衍射XRD、组成分析、热分析(TG+DTA)和红外分析FT-IR等多种手段,对内蒙古准格尔旗某煤系高岭石煅烧前后的结构进行了分析表征,了解其微观结构变化,以指导煅烧工艺条件的选择。 相似文献
88.
伊川半坡煤系高岭土矿床地质特征及找矿方向 总被引:1,自引:0,他引:1
伊川半坡煤系高岭土矿床的赋矿层位为二叠系石盒子组下段,矿石质优,规模可达中型(>200万t)。成矿受古地理沼泽—泻湖盆地控制,找矿前景较好。 相似文献
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90.
黏土矿物由于具有独特的层状纳米结构特性,在基础研究和实际应用中引起人们普遍的关注。但黏土矿物的亲水性表面使其对材料性能的提升产生限制,因此采用有机硅烷对黏土矿物进行表面改性是改善黏土矿物表面性质的有效方法之一。经过有机硅烷改性的黏土矿物既具有黏土矿物特有的尺寸稳定性、吸附性和阻隔性等性能,又具有硅烷分子多种功能基团的反应活性,在聚合物纳米复合材料、载体材料和环境材料等领域具有广阔的应用前景,已成为近年来矿物学和材料科学的研究热点之一。综述了不同类型黏土矿物有机硅烷改性的研究进展,讨论了黏土矿物类型、有机硅烷种类和反应条件对改性黏土矿物结构的影响,同时对黏土矿物有机硅烷改性未来主要研究方向进行展望。 相似文献