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1.
煤系高岭土制备氧化铝联产白炭黑工艺   总被引:1,自引:0,他引:1  
以煤系高岭土为原料,采用预脱硅碱石灰烧结法制备氧化铝和白炭黑粉体,考察了煤系高岭土的活化温度、液固比、氢氢氧化钠浓度、反应时间和温度等因素对脱硅率的影响,确定了适宜的工艺条件.运用X射线荧光分析(XRF)、X射线粉末衍射分析(XRD)、扫描电镜分析(SEM)、热重同步分析(DSC/TGA)等对原料和制品进行了表征.研究结果表明,制备的氧化铝粉体经800℃焙烧后为无定形γ–Al2O3,呈轻质多孔的蓬松纤维状,孔径为20~50 nm;白炭黑的颗粒之间形成三维网状结构,其内部疏松多孔,颗粒粒径为100 nm.  相似文献   

2.
中低品位铝土矿两段烧结法中一段烧结工艺研究   总被引:1,自引:1,他引:0  
用中低品位铝土矿(A/S为5左右)作为原料,通过纯碱烧结法考查碱比、烧结温度、烧结时间对氧化铝溶出率的影响。实验结果表明:碱比为1.2、烧结温度1100℃、烧结时间40min的烧结条件为一段烧结最佳条件。同时还考查了溶出条件对脱硅的影响作用。  相似文献   

3.
本文通过对潘二矿煤系高岭岩脱杂工艺实验,认为较佳脱杂效果的工艺条件为焙烧温度430℃,浸出温度120℃,盐酸浓度20%,浸出时间120min。  相似文献   

4.
低品位铝土矿预脱硅工艺及动力学研究   总被引:1,自引:0,他引:1  
为提高低品位铝土矿的铝硅比(A/S),采用了机械活化的方法处理.对山西普铝矿进行预脱硅的实验结果表明,80℃,在100g/LNa2Ok碱液中,经10min,未活化矿的脱硅率仅为7%左右;而活化矿的脱硅率则可达95%以上,A/S由原矿的4.83提高到精矿的20~40.动力学研究表明,活化矿和未活化矿的表观反应级数和表观活化能有显著差别.并初步分析了活化过程机理.  相似文献   

5.
针对富高岭石型铝土矿,首次提出了采用化学脱硅的工艺路线.研究了二氧化硅平衡溶解度与氧化铝质量浓度的变化关系,以及碱液浓度、温度和脱硅时间对矿石预脱硅率的影响.结果表明,在Na2O质量浓度为230g·L-1的碱溶液中,90℃化学脱硅90min,脱硅率可达70%,铝土矿的铝硅比由4.97提高到8.5以上;矿石预脱硅过程有钠硅渣的生成,导致了矿石脱硅率的降低和碱的损失;矿石中高岭石转变成钠硅渣并不会降低脱硅精矿的有效铝硅比.  相似文献   

6.
以Gd2O3、Al(NO3)3·9H2O和HNO3为原料,柠檬酸为络合剂,通过溶胶凝胶法制备前驱体,经过1000℃,保温2h热处理得到了纯相铝酸钆(GdAlO3)粉体。通过研究GdAlO3坯体样品的恒速无压烧结曲线发现,当升温速率为5℃/min时,样品在957℃开始收缩,烧结温度为1600℃时,最大收缩率为16.17%;通过计算得出GdAIO3坯体在烧结温度200-1000℃范围内平均线膨胀系数是9.38×10^-8/℃,以烧结曲线为基础,使用基于相对收缩率的Arrhenius关系,计算得到铝酸钆的烧结激活能为22.4kJ/mol,低于氧化铝的烧结激活能,说明其会促进氧化铝的烧结。  相似文献   

7.
添加石灰处理纯碱烧结法赤泥的研究   总被引:1,自引:0,他引:1  
论述了用石灰烧结法处理纯碱烧结法赤泥的研究,考查了钙比,烧结温度,烧结时间对氧化铝溶出率的影响。实验结果表明,石灰烧结法处理纯碱烧结法赤泥的最佳条件为:钙比2.25,烧结温度为1200,烧结时阃为40min.  相似文献   

8.
铝土矿浮选柱选矿脱硅试验研究   总被引:2,自引:0,他引:2  
利用2台直径为0.4m,长度为4m旋流-静态微泡浮选柱,采用一粗一精工艺,对中低铝硅比铝土矿进行脱硅试验,考察捕收剂用量、循环泵压力和处理量等因素对浮选效果的影响。结果表明:增加捕收剂用量有利于提高Al2O3回收率,当捕收剂用量为1.3kg/t时,精矿w(Al)/w(Si)为10.08,氧化铝回收率为84.36%;随循环泵压力增加,氧化铝回收率提高,泡沫铝硅比下降;当粗选循环泵压力为0.25MPa时,粗选作业段氧化铝回收率为90.11%,粗选泡沫w(Al)/w(Si)为7.26;当精选循环泵压力0.22MPa时,精矿w(Al)/w(Si)为10.03,精选作业段氧化铝回收率92.31%;随处理量的增加,精矿w(Al)/w(Si)、氧化铝回收率降低;当处理量为4.00t/(m2.h)时,精矿w(Al)/w(Si)为10.27,氧化铝回收率81.55%;72h稳定试验,浮选柱一粗一精两段分选作业,精矿w(Al)/w(Si)为为10.85,尾矿w(Al)/w(Si)为1.43,氧化铝回收率为80.43%,与浮选机相比精矿品位基本持平,回收率提高3.43%。铝土矿柱式浮选流程短,"一粗一精"两段工艺可以代替浮选机"一粗一扫两精一精扫"五段工艺。  相似文献   

9.
煤系高岭岩制洗衣粉助剂4A沸石   总被引:1,自引:0,他引:1  
在实验室条件下对煤系高岭岩等天然铝硅原料进行预处理,获得符合洗衣粉助剂用4A沸石。同时试验了工艺条件对4A产品质量的影响。  相似文献   

10.
利用硫酸铵焙烧工艺提取硼精矿中的硼   总被引:2,自引:0,他引:2  
为了更加合理有效地利用硼精矿,以辽宁硼铁矿经磁选得到的硼精矿为原料,采用硫酸铵焙烧的方法处理得到熟料,将熟料加水溶出、固液分离得到含硼溶液和提硼渣,含硼溶液用于提取硼酸,提硼渣可用于提取SiO2和MgO.通过单因素实验考察了焙烧温度、焙烧时间、铵矿比对B2O3浸出率的影响.通过正交试验得到提取B2O3的适宜工艺条件为:焙烧温度400℃,焙烧时间90 min,铵矿比1.6,该条件下B2O3的浸出率可达85%以上.对原料及提硼渣进行化学成分和物相组成分析,结果表明本工艺可使大部分硼化物生成可溶物并被提取出来,可实现硼精矿的绿色综合利用.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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