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1.
提出一个简便快速分离、原子吸收测定含高量贵金属试样中微量铑的方法。在3N盐酸介质中,用30%TAPO—CCl_4(V/V)萃取铱(Ⅳ)、铂(Ⅳ)、钯(Ⅳ)、金(Ⅲ)等贵金属,不必分出有机相,然后于水相中加入缓冲剂硝酸镧,直接喷雾水相测定微量铑。对稀释剂选择,萃取酸度,试液的预处理等进行试验,测定的标准偏差为0.32,变异系数约1%,可测定贵金属总量为100~150mg试样中10~100μg铑,回收率97~103%。  相似文献   

2.
姚慧  张仲荣  高俊华 《贵金属》2015,36(2):57-60, 65
铑在常态下难溶于王水等强酸,使用酸性溶液对耐强酸基体的车用陶瓷催化转化器中铑的完全溶出非常困难。采用微波消解法,研究了消解过程中酸的用量比例、消解温度及消解时间对铑溶出率的影响。结果表明,酸的用量比例对铑的溶出率影响不明显,溶解时间和消解温度对铑的溶出有显著影响。通过单因素试验分析,建立了一种新型耐强酸陶瓷催化转化器中铑元素的微波消解溶出方法,在消解时间为60 min,消解温度为212℃的条件下,铑的溶出率提高了25%。  相似文献   

3.
氢具有使贵金属离子还原成金属状态的能力。已研究从溶液中用H_2回收铂、铑、及钯。对单个贵金属溶液已测定温度、压力、气体组成、酸的性质和浓度的影响。为求得一些典型溶液的参数,也研究了由贵金属络合物和氨,氰化物,醋酸盐及硝酸盐等添加剂组成的更复杂溶液。从所获得的动力学数据提出一种还原机理。  相似文献   

4.
采用HNO_3-HClO_4消解样品除碘,王水溶解铑,以钇为内标,ICP-AES准确测定碘化铑中的铑含量。考察了样品消解处理和测定的最佳条件,并与硝酸六氨合钴重量法进行了比较,两者测定结果基本相符。方法精密度(RSD)1%(n=11),加标回收率99.00%~101.14%。方法快速、简便。  相似文献   

5.
将凝聚法和吸附法相结合,提出了一种从企业贵金属合金粉生产过程中形成的废水中分离回收贵金属(主要是银、钯)的新工艺。通过实验,研究分析了废料液的pH值、吸附时间、凝聚剂加入量、吸附剂加入量等操作条件对责金属回收效果的影响;找到了从废料液中回收贵金属的最佳工艺条件:pH值8~9;凝聚剂加入量与溶液的体积比为1:(2600~4000);吸附剂加入量与溶液的质量比为1:(20~40)。  相似文献   

6.
昆明贵金属研究所一室与化学制品车间合作,研究了从废铂铑(含少量铱)合金溶解液中,用萃取法分离提纯铂和铑的工艺流程.其方法要点是①用P204(二-2-乙基己基磷酸)萃取铑,分离铂和铑;②粗铑溶液通氯气氧化,用TAPO(三烷基氧化膦)萃取其中的微量铂、铱等贵金属杂质以纯化铑,离子交换除贱金属,甲酸还原,氢还原得纯铑;③粗铂溶液用氧化载体水解法提纯,氯化铵沉淀,锻烧得纯铂.原料溶液成分  相似文献   

7.
研究了硅铁合金富集物样品溶解条件及铁、硅对铂、钯、铑测定的干扰情况。在聚四氟乙烯消化罐中,用盐酸-双氧水(15+3)将样品于150℃恒温密闭消解8 h以上,用ICP-AES测定铂、钯、铑含量。结果表明,在选定的溶解和测定条件下,铂、钯、铑测定相对标准偏差<2%,加标回收率为97%~102%。与碱熔-碲共沉淀-ICP-AES法进行对比,结果一致性好。可满足硅铁合金富集物中铂、钯、铑的测定要求。  相似文献   

8.
再生专利     
从含有贵金属的废催化剂中回收贵金属专利申请号:02109402.0公开号:1448522申请人:中国石油化工股份有限公司、中国石油化工股份有限公司抚顺石油化工研究院从含有贵金属的废催化剂中回收贵金属,首先要对废催化剂进行预处理,使贵金属以有利于进一步处理的还原态形式存在;其次经过预处理的废催化剂用含有双氧水、氢离子和氯离子的混合溶液进行浸取,使贵金属组分以离子形态存在于混合溶液中;最后对含有贵金属离子的混合溶液进行处理,回收贵金属组分。比现有技术具有投资少、工艺流程简单、污染小、需用时间短、回收率高和易于工业化等优点。回…  相似文献   

9.
萃淋树脂CL—5401分离贵金属的研究   总被引:1,自引:1,他引:1  
蔡旭琪 《贵金属》1993,14(1):9-15
萃淋树脂CL—5401系烷基氧膦类萃取剂固化而得白色无臭无味的球状固体。在盐酸和硫酸及其混合溶液中,在较宽的酸度以及有大量贱金属存在情况下,应用CL—5401萃淋树脂有效分离贵金属与贱金属。Au、Pd、Pt的吸萃大于99%,Ir大于97%,贱金属不被吸萃。应用CL—5401分离铂铱,钯铱、铑铱、铂铑和钯铑等混合液,效果显著,是粗铑纯化的有效方法之一。还可以从铂、金、钯的精炼母液中回收贵金属,减少沉淀法中的贵金属渣再溶解过程。  相似文献   

10.
废贵金属催化剂中铑回收工艺研究进展   总被引:1,自引:0,他引:1  
综述了废贵金属催化剂中铑的回收、富集及精炼工艺,对铑回收技术发展前景进行了展望。  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.
Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.  相似文献   

14.
The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.  相似文献   

15.
The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.  相似文献   

16.
On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes' collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.  相似文献   

17.
An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films(NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be *5.0 J/m2 for Cu/Cr, *4.1 J/m2 for Cu/Ta,*2.8 J/m2 for Cu/Mo, *1.1 J/m2 for Cu/Nb, and *1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.  相似文献   

18.
A 17 vol% SiCp/Al–Mg–Si–Cu composite plate with a thickness of 3 mm was successfully friction stir welded(FSWed) at a very high welding speed of 2000 mm/min for the first time. Microstructural observation indicated that the coarsening of the precipitates was greatly inhibited in the heat-affected zone of the FSW joint at high welding speed, due to the significantly reduced peak temperature and duration at high temperature. Therefore, prominent enhancement of the hardness was achieved at the lowest hardness zone of the FSW joint at this high welding speed, which was similar to that of the nugget zone. Furthermore, the ultimate tensile strength of the joint was as high as 369 MPa, which was much higher than that obtained at low welding speed of 100 mm/min(298 MPa). This study provides an effective method to weld aluminum matrix composite with superior quality and high welding efficiency.  相似文献   

19.
吴玉梅  熊晓云  靳蓉  孙敬民  杨林  罗晓星 《金属学报》2005,10(10):1100-1103
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。  相似文献   

20.
On the basis of energy and shape method for the determination of the valence bond (VB) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is e_c~(2.9907) · (s_c~(0.4980) d_c~(2.4927)) ef1.0093 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.  相似文献   

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