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1.
崔学茹 《科技资讯》2023,(12):88-91
辽宁某钾长石矿原矿中K2O品位为5.21%,Na2O品位为3.07%,TFe2O3品位为1.09%,TiO2品位为0.054%,SiO2品位为69.47%,Al2O3品位为13.45%。原矿K2O+Na2O=8.28%品位偏低,而杂质铁、硅含量偏高,不能直接用于高档陶瓷生产,需要采用选矿提纯技术对其中的铁、硅等杂质去除,提高K2O+Na2O的品位。试验研究采用强磁-脱泥除铁,粗精矿进行长石-石英浮选分离的选矿提纯工艺,可获得K2O品位为6.23%、Na2O品位为4.07%,K2O+Na2O=10.30%,TFe2O3品位为0.28%,K2O回收率为79.37%,Na...  相似文献   

2.
In pyrometallurgical process, Al-and Si-bearing minerals in iron and aluminum ores are easily transformed into sodium aluminosilicates in the presence of Na2O constituents, which alters the leaching behaviors of Al2O3 and SiO2. It was confirmed that sodium aluminosilicates with different phase compositions synthesized at various roasting conditions were effectively digested in the alkaline digestion process. Under the optimum conditions at temperature of 100-120℃, liquid-to-solid ratio (L/S) of 10:2 mL/g, caustic ratio of 4, and Na2O concentration of 240 g/L, the actual and relative digestion ratio of Al2O3 from the synthesized sodium aluminosilicates reached maximums of about 65% and 95%, respectively, while SiO2 was barely leached out. To validate the superior digestion property of sodium aluminosilicate generated via an actual process, the Bayer digestion of an Al2O3-rich material derived from reductive roasting of bauxite and comprising Na1.75Al1.75Si0.25O4 was conducted; the relative digestion ratio of Al2O3 attained 90% at 200℃.  相似文献   

3.
海滩岩是形成于潮间带,由碳酸盐胶结海滩沉积物而成的一种海岸带碳酸盐胶结岩,对于研究古海平面变化、海岸带演化以及古气候变化等海陆相互作用过程具有重要意义。对海滩岩的岩石学、地球化学特征进行了研究,结果表明:海滩岩主量元素与上部陆壳(upper continental crust, UCC)的平均含量比较,显著富集MgO和CaO,略富集MnO,其他均亏损,其中Na2O亏损最大。6件海滩岩稀土元素(rare earth element, REE)总体呈微弱的右倾轻稀土富集型曲线,轻、重稀土分异不强,以Eu弱负异常,Ce弱负异常及La弱正异常为特征;从早到晚,Al2O3/MgO比值变小和陆源碎屑组分SiO2、Al2O3、Na2O、K2O、TiO2等含量逐渐下降共同反映陆源的化学风化减弱,气候越来越干旱。古盐度Z值、Sr/Ba、Rb/K、V/Cr、V/(V+Ni)和稀土元素判别研究区为弱氧化-氧化的海...  相似文献   

4.
对海南岛东北部文昌坑尾园风成砂物质基础上发育的现代“红色沙壤”中SiO2、Al2O3、TOFE、CaO、Na2O、K2O、MgO这7种主量元素的研究发现:现代红色沙壤土中SiO2含量最高,MgO含量最低;CIA分别与Saf和ba存在负相关关系且剖面上下部数据变化符合土壤自剖面底到顶风化程度变弱的规律;坑尾园剖面高CIA值,与该地所处的热湿环境相关。在此环境下,水土流失带来元素迁移,使得除SiO2外的6种元素值均因减少而处于低值状态。  相似文献   

5.
The mineral transition and formation mechanism of calcium aluminate compounds in CaO?Al2O3?Na2O system during the high-temperature sintering process were systematically investigated using DSC?TG, XRD, SEM?EDS, FTIR, and Raman spectra, and the crystal structure of Na4Ca3(AlO2)10 was also simulated by Material Studio software. The results indicated that the minerals formed during the sintering process included Na4Ca3(AlO2)10, CaO·Al2O3, and 12CaO·7Al2O3, and the content of Na4Ca3(AlO2)10 could reach 92wt% when sintered at 1200°C for 30 min. The main formation stage of Na4Ca3(AlO2)10 occurred at temperatures from 970 to 1100°C, and the content could reach 82wt% when the reaction temperature increased to 1100°C. The crystal system of Na4Ca3(AlO2)10 was tetragonal, and the cells preferred to grow along crystal planes (110) and (210). The formation of Na4Ca3(AlO2)10 was an exothermic reaction that followed a secondary reaction model, and its activation energy was 223.97 kJ/mol.  相似文献   

6.
针对Al2O3和膨胀石墨(EG)单独作为吸附剂时存在不易分离和吸附性能较差等问题, 以EG为骨料、  Al(NO3)39H2O为铝源、  NH3H2O为沉淀剂、  无水乙醇为分散剂制备纳米Al2O3/EG, 并用Fourier变换红外光谱(FT-IR)、  X射线衍射(XRD)和扫描电子显微镜(SEM)等方法对吸附剂进行表征; 以Al2O3/EG为吸附剂, 对刚果红溶液进行吸附, 并考察加氨水方式、  活化温度、  活化时间、  Al2O3与EG质量比和浸渍时间对吸附性能的影响. 结果表明:  纳米级Al2O3成功负载在EG上; 逐滴加入氨水、  活化温度170 ℃、  活化时间3 h、  Al2O3与EG质量比为0.06∶1、  浸渍时间为20 min时, 吸附效果最好, 脱色率约为86%;  Al2O3/EG明显优于EG的吸附效果, 其脱色率是EG的2倍以上; 与Al2O3相比, 在吸附后的分离操作中, Al2O3/EG更易分离.  相似文献   

7.
基于电厂失活催化剂,采用物相分析、化学组分测试、比表面积测量表征手段确定导致V2O5/TiO2失活的原因为As2O3、碱金属中毒,而失活催化剂晶型结构没有发生改变且具有高的比表面积.采用0.01mol/L 的H2C2O4溶液和0.015mol/L的NH3·H2O溶液对催化剂进行洗涤再生处理可将催化剂表面SO3,As2O3,K2O和Na2O质量分数分别降至0.09%,0.05%,0.02%和0.01%,重新负载1.5%质量分数V2O5后催化剂活性得以恢复.负载3%质量分数CuO后催化剂表现出好的低温催化活性,220℃, 250℃, 280℃ 和 310℃下V2O5-CuO/TiO2的NOx转化率分别为62.4%, 82.2%, 90.8%和95.5%.  相似文献   

8.
 多金属氧酸盐作为一种无机金属-氧簇化合物,在抗肿瘤、抗病毒等药物化学领域引起广泛关注。研究了以下5种含5-氟尿嘧啶稀土磷钨酸盐K9(C4H4FN2O22La(PW11O392·18H2O,K9(C4H4FN2O22Ce(PW11O392·23H2O,K9(C4H4FN2O22Nd(PW11O392·25H2O,K9(C4H4FN2O22Sm(PW11O392·11H2O和K9H(C4H4FN2O2)Eu(PW11O392·11H2O(FLnPW,Ln=La、Ce、Nd、Sm、Eu)对HeLa细胞凋亡和周期的影响,以5-氟尿嘧啶为阴性对照,同时比较了含5-氟尿嘧啶磷钨酸盐K11C4H4FN2O2(PW11O39)·7H2O(FPW)及磷钨酸H3PW12O40(PW)的生物活性。细胞形态检测表明,化合物作用于HeLa细胞后均出现明显凋亡形态特征,细胞核染色质呈高度浓缩和边缘化现象(PW除外)。流式细胞周期检测表明,化合物作用后HeLa细胞均出现S期阻滞,与5-氟尿嘧啶相比,FPW作用后S期阻滞增强,而FCePW、FNdPW和FEuPW组同时出现S期和G2/M期阻滞。流式细胞检测表明,化合物诱导HeLa细胞发生凋亡(PW除外),且诱导凋亡活性顺序为FLnPW > FPW > 5-氟尿嘧啶。Caspase 3检测表明,化合物作用后Caspase 3活性增强(PW除外),活性顺序与凋亡活性顺序相同,其中FCePW组和FEuPW组Caspase 3相对活性显著增强。实验结果表明,所考查化合物(PW除外)能诱导细胞周期阻滞、诱导凋亡活性以及激活Caspase 3,且FLnPW的活性均高于FPW和5-氟尿嘧啶,而PW只能使肿瘤细胞发生坏死,说明5-氟尿嘧啶和稀土元素对化合物的抗肿瘤活性发挥关键作用,FLnPW可能是通过诱导细胞周期阻滞以及激活Cas-pase 3细胞凋亡通路,实现显著抑制HeLa细胞增殖。  相似文献   

9.
高炉渣系各组元活度对高炉冶炼和产品质量具有重要的影响作用. 基于分子-离子共存理论,建立CaO-SiO2-MgO-Al2O3四元渣系Al2O3活度预测模型;结合试验测定值对其进行验证与修正,最终建立了修正的CaO-SiO2-MgO-Al2O3四元渣系Al2O3活度预测模型;同时,依据模型计算结果探究R(w(CaO)/w(SiO2)),w(MgO)/w(Al2O3)和w(Al2O3)对Al2O3活度的影响. 研究结果表明:修正后的CaO-SiO2-MgO-Al2O3四元渣系Al2O3活度预测模型具有较高的预测精度,能够很好地预测熔渣Al2O3活度;当w(MgO)/w(Al2O3)=0.40,w(Al2O3)=20%时,随着R增加,Al2O3活度逐渐减小;当R=1.25,w(Al2O3)=20%时,随着w(MgO)/w(Al2O3)增加,Al2O3活度逐渐减小;当w(MgO)/w(Al2O3)=0.40,R=1.25时,随着w(Al2O3)增加,Al2O3活度逐渐增大.  相似文献   

10.
Metal Sm has been widely used in making Al-Sm magnet alloy materials. Conventional distillation technology to produce Sm has the disadvantages of low productivity, high costs, and pollution generation. The objective of this study was to develop a molten salt electrolyte system to produce Al-Sm alloy directly, with focus on the electrical conductivity and optimal operating conditions to minimize the energy consumption. The continuously varying cell constant (CVCC) technique was used to measure the conductivity for the Na3AlF6-AlF3-LiF-MgF2-Al2O3-Sm2O3 electrolysis medium in the temperature range from 905 to 1055℃. The temperature (t) and the addition of Al2O3 (W(Al2O3)), Sm2O3 (W(Sm2O3)), and a combination of Al2O3 and Sm2O3 into the basic fluoride system were examined with respect to their effects on the conductivity (κ) and activation energy. The experimental results showed that the molten electrolyte conductivity increases with increasing temperature (t) and decreases with the addition of Al2O3 or Sm2O3 or both. We concluded that the optimal operation conditions for Al-Sm intermediate alloy production in the Na3AlF6-AlF3-LiF-MgF2-Al2O3-Sm2O3 system are W(Al2O3) + W(Sm2O3)=3wt%, W(Al2O3):W(Sm2O3)=7:3, and a temperature of 965 to 995℃, which results in satisfactory conductivity, low fluoride evaporation losses, and low energy consumption.  相似文献   

11.
Red mud produced in the Bayer process is a hazardous solid waste because of its high alkalinity; however, it is rich in valuable components such as titanium, iron, and aluminum. In this study, a novel calcification–carbonation method was developed to recover alkali and alumina from Bayer red mud under mild reaction conditions. Batch experiments were performed to evaluate the potential effects of important parameters such as temperature, amount of CaO added, and CO2 partial pressure on the recovery of alkali and alumina. The results showed that 95.2% alkali and 75.0% alumina were recovered from red mud with decreases in the mass ratios of Na2O to Fe2O3 and of Al2O3 to Fe2O3 from 0.42 and 0.89 to 0.02 and 0.22, respectively. The processed red mud with less than 0.5wt% Na2O can potentially be used as a construction material.  相似文献   

12.
以考古发现为线索,结合文献研究和实物比对,利用现代大型仪器检测设备,分析了贵州出土玉器的时代特点和玉质材料。这些玉器的玉材种类非常丰富,并具有时代和地域特色。两汉时期以前,贵州透闪石材质的玉器很少,之后和田玉玉器数量占据主体地位。根据孔雀石和贵州罗甸和田玉的地质与矿物学分析,探讨了贵州古代早期玉料来源“就近取材”的可能性。贵州罗甸和田玉化学成分中的Na2O和K2O质量分数较高,Al2O3与MnO质量分数较低,这与古代其他产地的和田玉的化学成分有明显区别。  相似文献   

13.
熔渣粘度对冶炼过程中渣金反应的传质有着至关重要的作用,适当的熔渣粘度能够有效促进渣金反应,提升传质效率。为了促进含铬熔渣中铬的回收利用,本文使用柱体旋转法研究了Al2O3含量变化对CaO-SiO2-Cr2O3-Al2O3渣粘度和结构的影响规律。熔渣在高温下表现出良好的牛顿流体行为。当Al2O3含量从0%增加到10wt%时,酸性渣的粘度首先从0.825增加到1.141 Pa·s,然后当Al2O3含量进一步增加到15wt%时,粘度降低到1.071 Pa·s。当Al2O3含量从0增加到15wt%时,碱性炉渣的粘度首先从0.084增加到0.158Pa·s,然后当Al2O3含量进一步增加到20wt%时,粘度降低到0.135 Pa·s。此外,含Cr2O3的炉渣比无Cr2O3的炉渣需要更少的Al2O3才能达到最大粘度;对于酸性和碱性炉渣,熔渣粘度达到最大值所需的Al2O3含量分别为10%和15%。熔渣的活化能变化规律与粘度结果一致。拉曼光谱表明,熔渣中仅有少量Al2O3时,Al以[AlO4]四面体形式出现,随着Al2O3含量的逐渐增加,[AlO4]四面体被[AlO6]八面体所取代,对硅酸盐结构的分峰解谱结果也与粘度结果一致。  相似文献   

14.
针对添加活性元素Ti有利于改善金属/Al2O3体系的润湿性、但润湿机制仍不明确问题,研究采用改良座滴法,研究了熔融Sn-(原子分数为0%、2%、5%)Ti合金在973~1 273 K高真空中在Al2O3表面的润湿性.研究结果表明:Ti原子分数的增加会显著改善Sn-xTi/Al2O3体系的润湿性,润湿性改善的原因在于Ti在界面处的吸附降低了固/液界面自由能,而并非界面析出的反应产物.对此结论,应用吸附的统计热力学模型验证了实验结果,并证明Sn-xTi/Al2O3体系的铺展动力学在很大程度上受控于吸附动力学.  相似文献   

15.
The thermodynamic behavior of manganese and phosphorus between liquid iron and CaO-MgO-SiO2-Al2O3-FetO-MnO-P2O5 ladle slag system was addressed by investigating the thermodynamic equilibria between liquid iron containing Mn and P and the ladle slag at 1873 K. The Mn distribution ratio LMn increases with increasing FetO content and decreasing the basicity ((%CaO + %MgO)/(%SiO2 + %Al2O3 + %P2O5)) in slag, while the P distribution ratio Lp seems to be increased as FetO content and the basicity increases. The values of LMn and Lp decrease by the addition of Al2O3 into slag. The expression of the dependence of LMn and Lp on the basicity and FetO content in slag was obtained.  相似文献   

16.
The carbothermic reduction of vanadium titanomagnetite concentrate(VTC)with the assistance of Na2CO3was conducted in an argon atmosphere between 1073 and 1473 K.X-ray diffraction and scanning electron microscopy were used to investigate the phase transformations during the reaction.By investigating the reaction between VTC and Na2CO3,it was concluded that molten Na2CO3broke the structure of titanomagnetite by combining with the acidic oxides(Fe2O3,TiO2,Al2O3,and SiO2)to form a Na-rich melt and release FeO and MgO.Therefore,Na2CO3accelerated the reduction rate.In addition,adding Na2CO3also benefited the agglomeration of iron particles and the slag–metal separation by decreasing the viscosity of the slag.Thus,Na2CO3assisted carbothermic reduction is a promising method for treating VTC at low temperatures.  相似文献   

17.
以农业副产物稻壳为硅源、 硫酸铝为铝源, 通过炭化、 碱溶和水热合成工艺, 无需老化过程及添加晶种制备了洗涤助剂P型分子筛, 并考察了硅铝比、 碱度比、 反应时间和反应温度对合成分子筛的影响. 实验结果表明, 分子筛合成的最佳条件为: n(Na2O) ∶n(SiO2)=1.43, n(SiO2) ∶n(Al2O3)=4,  n(H2O) ∶n(Na2O)=18.3, 在85 ℃反应8 h. 产品的XRD和SEM表征表明, 上述条件下合成的P型分子筛产品具有较高的结晶度, 无杂相且晶粒细小, 其Ca2+交换容量可达330 mg/g.  相似文献   

18.
试验研究了利用二元钠盐(NaOH-Na2CO3)对钒渣进行焙烧,并分析了相关动力学参数对焙烧效果的影响.结果表明:在二元钠盐焙烧过程中,焙烧温度、焙烧时间及NaOH与Na2CO3质量比对渣中钒、铬的浸出率影响重大;焙烧过程中,Fe3O4被氧化为Fe2O3,V2O5和Cr2O3分别被氧化为β钒酸钠型结构的Na3VO4与正交晶系结构的Na2CrO4;最佳焙烧条件下,NaOH与 Na2CO3质量比为1.5∶1,焙烧温度为600℃,焙烧时间为60min,此时钒与铬的浸出率分别为98.66%与83.57%;浸出尾渣的主要金属元素为Fe.  相似文献   

19.
Analytical-reagent-grade Al2O3 was added to magnetite ore during the process of pelletizing, and the methods of mercury intrusion, scanning electron microscopy, and image processing were used to investigate the effect of Al2O3 on the compressive strength of the pellets. The results showed that, as the Al2O3 content increased, the compressive strength of the pellets increased slightly and then decreased gradually. When a small amount of Al2O3 was added to the pellets, the Al2O3 combined with fayalite (2FeO·SiO2) and the aluminosilicate (2FeO·2Al2O3·5SiO2) was generated, which releases some iron oxide and reduces the inhibition of fayalite to the solid phase of consolidation. When Al2O3 increased sequentially, high melting point of Al2O3 particles hinder the oxidation of Fe3O4 and the recrystallization of Fe2O3, making the internal porosity of the pellets increase, which leads to the decrease in compressive strength of the pellets.  相似文献   

20.
MnO–SiO2二元系作为废旧锂离子电池、海洋锰结核还原熔炼过程中的基础渣型,测定有价金属(如镍)在渣中的溶解度、活度及活度系数热力学数据十分必要。为此,本文测定了温度1623 K、氧分压10?7,10?6,和10?5 Pa时SiO2饱和的MnO–SiO2渣和Al2O3饱和的MnO–SiO2–Al2O3渣中NiO的溶解度和活度系数。结果表明:在试验条件下,镍在MnO–SiO2渣和MnO–SiO2–Al2O3渣中主要以NiO形式存在,且渣中NiO的溶解度随着氧分压增加而增加;向MnO–SiO2渣中加入Al2O3可以降低渣中镍的溶解度,增加NiO的活度系数。此外,SiO2饱和的MnO–SiO2渣和Al2O3饱和的MnO–SiO2–Al2O3渣中NiO的活度系数(γNiO,以纯固体NiO为参考态)可分别按如下公式计算:γNiO = 8.58w(NiO) + 3.18; γNiO=11.06w(NiO) + 4.07, 其中,w(NiO)为渣中NiO的质量分数。  相似文献   

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