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以天然矿物高岭土为主要硅铝原料,经低温固相碱熔活化后,在常规水热条件下合成ZSM-5分子筛,考察m(高岭土)∶m(氢氧化钠)、碱熔温度及碱熔时间等因素对高岭土活化效果的影响。采用XRF、XRD、FT-IR和N2-吸脱附等对不同样品进行表征。结果表明,在m(高岭土)∶m(氢氧化钠)=1∶1.5、碱熔温度250℃和碱熔时间30 min条件下,可以实现高岭土完全活化。该活化方式不仅降低了活化温度,且能在极短时间内提高高岭土活性。以最适宜低温固相碱熔活化条件下所得活性硅铝物质为主要原料,硅溶胶为外加硅源,采用水热法合成高相对结晶度的纯相ZSM-5分子筛。与工业ZSM-5分子筛相比,合成ZSM-5分子筛具有更大的比表面积和孔容。 相似文献
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粉煤灰因其主要成分为二氧化硅、三氧化二铝常被用来当作合成沸石的原材料,合成的沸石类型主要有X型、Y型、A型、ZSM-5型等,相关合成技术也已非常成熟。水淬渣是高炉炼铁水淬急冷产生的高炉渣,对其主要利用方式是作为水泥、路基材料,均属低附加值利用。通过碱熔水热法利用水淬渣、粉煤灰混合原料合成4A型沸石。初步探究硅铝物质的量比(简称硅铝比)、熔融温度、熔融时间、晶化时间对制备的沸石样品品质造成的影响,得到最佳制备条件:硅铝比为1.0、碱灰质量比为1.5、碱熔时间为1 h、碱熔温度为600 ℃、老化时间为12 h、灰水质量比为1∶5、晶化温度为90 ℃、晶化时间为16 h。对合成的沸石进行X射线衍射(XRD)、X射线荧光光谱(XRF)、扫描电镜(SEM)、红外光谱(FT-IR)等表征,结果表明利用水淬渣、粉煤灰合成的4A型沸石各方面性能良好,具有超高的工业化生产价值。 相似文献
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周先萍 《中国石油和化工标准与质量》2023,(20):61-63
本方法利用碱熔-电感耦合等离子体发射光谱法测定岩石样品中的铝、铁、钛的含量,测试结果准确度:-4.71%~4.68%;精密度:1.31%~6.71%。结果准确,重复性好,方法适用。 相似文献
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以碱熔分解样品,采用HgNO3作滴定剂,KCNS作指示剂测定高岭土中铁,在滴定铁后的溶液中,以锌盐作滴定剂,5-Br-PADAP作指示剂测定高岭土中铝,实现了高岭土中铝铁含量的连续测定,RSD均小于3%,测定值与国标法测定值比较,结果吻合. 相似文献
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本文主要建立了利用铬天青S测定水泥中Al2O3的方法。水泥试样通过碱熔的方法处理,用抗坏血酸和苯羟乙酸分别消除铁和钛的干扰,在HAc-Na Ac缓冲体系中,铝、铬天青S和聚乙烯醇三者生成紫红色络合物,其吸光度与铝离子浓度呈线性关系。基于此,本文主要利用分光光度法针对水泥样品中的铝离子进行了测定。优化后的方法线性范围为0~1. 00μg/m L,检出限为0. 13μg/m L。水泥中主要成分对测定的干扰可消除,成功测定了水泥样品中铝的含量。 相似文献
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A potentiostatic double pulse method has been developed for the measurement of current efficiency of aluminium deposition from cryolitic melts on solid substrates. The method is based on the measurement of the ratio of anodic to cathodic charge. Its application is at present limited to laboratory cells. The method described is useful for the study of the influence of different parameters such as electrolyte composition, temperature or convection conditions on current efficiency for aluminium deposition. 相似文献
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实验以矾浆为原料,利用酸熔法从中提取氢氧化铝。考察了固液比、反应温度、硫酸浓度等因素对氢氧化铝提取率的影响,通过正交试验确定了最佳的工艺条件,硫酸浓度为60%,固液比1∶3,反应温度为175℃,在此条件下氢氧化铝的提取率可达87.07%。 相似文献
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In this paper, the temperature fields of unprotected and protected aluminium‐alloy I‐beams heated on three sides were calculated using the finite element method. The calculated temperature results were compared with the incremental temperature rise formulas specified in Eurocode 9. Next, finite element models were developed to simulate the flexural behaviour and the flexural–torsional buckling behaviour of aluminium‐alloy I‐beams under fire. The calculated results were validated by experimental data acquired at both ambient and high temperatures. Subsequently, simplified formulas for calculating critical temperatures for 5083‐H112 and 6060‐T66 aluminium‐alloy beams were proposed based on parametric analysis, and the results obtained using these formulas were compared against equivalent values calculated in accordance with Eurocode 9 standards. In terms of engineering applications, findings indicate that increases in the load level, the global stability coefficient, and the ratio of fireboard thickness to thermal conductivity reduce the critical temperatures of aluminium‐alloy beams. In most cases, designs using the method of checking load bearing capacity at high temperature published in the Eurocode 9 would tend to be conservative. Finally, when the global stability coefficient was greater than 0.8, the critical temperatures in some regions measured slightly higher than the calculated simplified value. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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The electrodeposition of aluminium was carried out successfully in AlCl3-LiAlH4/tetrahydrofuran-toluene solutions. The kinetic parameters controlling the cathodic deposition and anodic dissolution of aluminium were derived. The effect of the total concentration of aluminium and the molar ratio of AlCl3 to LiAlH4 on the current density-potential behaviour of the rotating disc aluminium electrode was also studied. A detailed mechanism for the electrode reactions was suggested. 相似文献
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A comparative study of aluminium electrodeposition from xylene and ether electrolytes is presented. The kinetic parameters of aluminium deposition from the tetrahydrofuran (THF) and xylene electrolytes are presented. In the case of the THF and diethylether solutions investigations of aluminium nucleation were also made. It was found that the rate of aluminium deposition was highest in the THF electrolyte composed of AlCl3 and LiAlH4 in a ratio 1:1. This electrolyte is recommended for deposition of aluminium protective coatings of thickness over 20 µm 相似文献