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1.
水溶液氯化法快速溶解纯铑粉   总被引:1,自引:1,他引:0       下载免费PDF全文
采用水溶液氯化法,在盐酸-氯酸钠体系中溶解铑粉,考察了反应温度、酸度、氧化剂用量、时间、液固比等因素对铑溶解率的影响。结果表明,浓盐酸升温至85℃后开始加氯酸钠,酸度为8~9 mol/L,饱和氯酸钠溶液用量为250 m L,液固比为45 m L/g,反应时间2 h,铑粉的一次溶解率达到95%以上。机理探讨认为,充当氧化剂的Cl O_3-在酸性条件下产生的活性[Cl],将金属态的铑氧化,并与体系中的Cl-配位形成[Rh Cl_3]~(3-)。  相似文献   

2.
难溶铑物料高温高压快速溶解技术研究   总被引:1,自引:3,他引:1       下载免费PDF全文
铑粉的溶解是铑精炼提纯中的重要环节。传统方法溶解周期长,转化率低,易引入污染,使用高压釜在高温高压下溶解铑粉具有较强的应用前景。研究了液固比、盐酸浓度、温度等因素对铑粉浸出的影响。得到的最佳浸出工艺条件为:液固比10:1,盐酸浓度5 mol/L,反应温度200℃,氧气分压0.5 MPa,氯酸钠氧化剂用量为铑粉量的4倍。在400 r/min搅拌转速下反应,经3 h铑粉的一次浸出率达到99%以上。  相似文献   

3.
采用水溶液氯化法、王水溶解法和水溶液氯酸钠氧化法等3种湿法工艺从含铑树脂中回收铑,重点研究了溶解体系、反应温度、反应时间和液固比等对铑溶解率的影响。结果表明,在液固比12:1 mL/g、反应温度90℃、反应时间20 h的条件下,采用水溶液氯化法铑溶解率达到95%,经精炼后得到合格铑粉,铑的回收率达到92%。  相似文献   

4.
郝婷婷  蒋凌云  于海斌  臧甲忠 《贵金属》2018,39(S1):117-119
铑的高效快速溶解是其冶金领域的关键环节,并且是公认的技术难题。研究了电化学溶解铑的工艺,探索了液固比、电极直径大小、反应液中铑浓度对铑粉溶解速率的影响。结果表明,合理的液固比为15~90 mL/g;电极直径越大铑粉溶解速度越快;铑浓度过高抑制铑粉的溶解。在最佳反应条件下铑粉溶解速率为1 g/h。  相似文献   

5.
采用响应曲面法中的中心组合模式对偏钒酸铵煅烧制备V2O5工艺条件进行优化,建立偏钒酸铵煅烧制备V2O5的二次多项式数学模型,探讨主要因素的影响及其交互作用。方差分析结果表明:煅烧温度和煅烧时间对偏钒酸铵的分解率都有显著的影响。采用响应曲面法优化得出的最佳工艺条件为:煅烧温度669.71K,煅烧时间35.9min,物料量4.25g。在最佳工艺条件下,偏钒酸铵的分解率预测值为99.71%,其与实验值99.27%相近,证实回归方程拟合度良好。XRD分析表明,采用响应曲面法所得的煅烧工艺参数是可行的。  相似文献   

6.
以提高铟浸出率为目标,通过工艺实验结合神经网络研究ITO废靶酸浸的优化工艺。首先,固定其他工艺因素,进行单因素如残酸度、氧化剂加入量、酸浸温度及时间对铟浸出率影响的实验研究。结果表明,增大残酸度可提高铟浸出率;氧化剂的加入可明显提高铟浸出率,但增加到一定程度后浸出率提高不明显;升高温度可明显提高浸出率,但继续升高则会降低铟浸出率;延长浸出时间也可提高铟浸出率。通过反向传播算法的人工神经网络(BPNN)研究多因素的综合作用对铟浸出率的影响规律,预测值与实验值相差很小,表明所建立的BP模型铟浸出率能比较准确地预测。最终,通过BPNN预测以及实验验证,获得高达99.5%浸出率的工艺参数:残酸度50~60 g/L、氧化剂含量10%、浸出温度70°C和浸出时间2 h。  相似文献   

7.
为了回收含锑金精矿中的锑,减少锑对两段焙烧过程的影响,对浮选富集得到的含锑金精矿进行硫化钠碱性浸出锑研究。优化实验表明,在液固比1.5:1 (mL/g),氢氧化钠用量20 g/L,硫化钠用量40 g/L,反应温度80℃,浸出30 min,锑浸出率可达98%以上。在此基础上,采用焙烧炉余热将电解贫液加温至80℃,对液固分离方式、锑电积阴阳极板和冷冻结晶装置进行工艺改造,使锑的浸出率>98%、阴极锑纯度>95%,日产锑量增加17.35%。  相似文献   

8.
为了对制备乙醇胺铂(Ⅳ)的工艺进行优化,在铂浓度、氧化剂用量、氢氧化钠用量等单因素设计和实验结果的基础上,采用响应曲面法优化合成条件,建立预测乙醇胺铂(Ⅳ)产率的数学模型。结果表明,影响因子显著性顺序为:铂浓度NaOH用量氧化剂用量。当铂浓度为100 g·L~(-1),NaOH用量为2.25倍,氧化剂用量为10%时,预测乙醇胺铂(Ⅳ)的产率为89.26%。实验证明,该模型对乙醇胺铂(Ⅳ)制备条件的优化及产率的预测较为准确可靠。通过样品表征,验证了该化合物的结构式为(NH_3CH_2CH_2OH)_2Pt(OH)_6。  相似文献   

9.
铑溶解提纯工艺的试验研究   总被引:1,自引:0,他引:1  
进行了金属铑化学溶解的探索试验,发现在盐酸中引入由助溶剂ZRJ和适当的添加剂组成的混合溶剂,可使铑粉快速有效地溶解。通过采用正交试验优化法方案,确定了最佳的工艺配方和溶解反应条件,考察了各因素对铑粉溶解速度的影响。该方法应用于铑的精炼提纯工艺,可有效地提高铑的回收率。  相似文献   

10.
《轻金属》2018,(12)
为确定氢氧化钾溶液对钾长石的最佳活化工艺条件,采用响应曲面法的中心复合设计对钾长石活化工艺条件进行了优化设计。通过对不同工艺条件下获得的氧化铝的提取率进行二次多项式回归得到了相应数学模型。结果表明,活化钾长石的主要影响因素依次为活化温度、活化时间、氢氧化钾浓度和过量率。活化温度为279. 3℃、活化时间为143. 1min、氢氧化钾的浓度为45%、氢氧化钾的过量率为90%时为最优影响因素指标组合,该条件下氧化铝的提取率可达99. 28%。  相似文献   

11.
In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.  相似文献   

12.
After nearly two years' tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry (SRIF), located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.  相似文献   

13.
The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).  相似文献   

14.
The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.  相似文献   

15.
Tang Dynasty 《中国铸造》2014,(4):I0002-I0003
<正>Bronze mirrors were used by the Chinese people before the introduction of the glass mirror.Only after it was replaced by the glass mirror did the bronze mirror gradually retreat from people's lives.Different styles of bronze mirrors were made in different historical periods,particularly in the Warring States Period,the Han and Tang Dynasties,which were the three peaks of the development of bronze mirror arts in ancient China.The casting techniques were exquisite.The surface of the bronze mirror was smooth and bright enough to reflect one's image,and there were scarcely any casting defects on the mirror surface.On the back of the bronze mirror,there were rich depictions of Arts and Humanities,and the ornamentations were also  相似文献   

16.
《中国铸造》2014,(5):464-466
The 9th China International Diecasting Congress & Exhibition was held on July 22-24, 2014 at Shanghai New International Expc Centre. This exhibition was the most successful over the years, with over 6890 visitors and 155 exhibitors, and the exhibition area increased by 30% from 9,500 square meters in 2012 to 12340 square meters. Die casting enterprises from a total of 24 countries and regions, including China mainland, Chinese Taiwan and Hong Kong, South Korea, Japan, Germany, India, Thailand, Malaysia, the United States, Russia, Australia, Iran, Ukraine, Brazil, Colombia, Singapore, Austria, Canada, Croatia, France, Turkey, United Kingdom, Vietnam, attended the congress and exhibition.  相似文献   

17.
正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-  相似文献   

18.
19.
Antimony induced crystallization of PVD (physics vapor deposition) amorphous silicon can be observed on sapphire substrates. Very large crystalline regions up to several tens of micrometers can be formed. The Si diffraction patterns of the area of crystallization can be observed with TEM (transmission electron microscopy). Only a few and much smaller crystals of the order of 1μm were formed when the antimony layer was deposited by MBE (molecular beam epitaxy) compared with a layer formed by thermal evaporation. The use of high vacuum is essential in order to observe any Sb induced crystallization at all. In addition it is necessary to take measures to limit the evaporation of the antimony.  相似文献   

20.
Fatigue damage increases with the applied loading cycles in a cumulative manner and the material deteriorates with the corrosion time. A cumulative fatigue damage rule under the alternative of corrosion or cyclic loading was proposed. The specimens of aluminum alloy LY12-CZ soaked in corrosive liquid for different times were tested under the constant amplitude cyclic loading to obtain S-N curves. The test was carried out to verify the proposed cumulative fatigue damage rule under the different combinations among corrosion time, loading level, and the cycle numbers. It was shown that the predicted residual fatigue lives showed a good agreement with the experimental results and the proposed rule was simple and can be easily adopted.  相似文献   

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