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1.
王毓明  陈金生 《电化学》1996,2(4):439-443
镉镍电池和氢镍电池同以镍电极作正极,但两者的充,放电过程,特别是过充,过放时所表现的特性存在诸多差异,我们比较,探讨了影响这两种电池性能的差异因素,并由此制定了改进电池性能的有产工艺生产措施。  相似文献   

2.
生物浸出回收废弃镍-镉电池研究   总被引:6,自引:0,他引:6  
夏良树  傅仕福  陈仲清 《电化学》2006,12(3):345-348
在中国,只有不到1%的废弃干电池被回收,因此有必要寻找一种既经济、快速,又利于环保的处理废弃干电池方法.生物浸出是回收废弃干电池有毒金属效果最好的方法之一.本研究应用本地下水道废水经驯化培养后产生的酸性废水作浸出菌种,考察pH值、生化反应器污水停留时间(RTB)、浸取时间、生化反应液是否添加Fe粉等实验条件对废弃镍-镉电池镍、镉浸出率的影响.结果表明,在pH值1.8~2.1、RTB 5 d、浸取时间50 d、生化反应液添加Fe粉条件下,可使镍-镉电池中镍、镉浸出率分别达到87.6%和86.4%,从而为工业生产提供了科学依据.  相似文献   

3.
高速率放电发泡式镍镉电池的研制   总被引:1,自引:0,他引:1  
王毓明 《电化学》1997,3(4):424-427
采取降低电池内阻,改善电极性能,选择合适的配件材料等有效措施,由此而制成的镍镉电池适用于高速率放电。  相似文献   

4.
采用火焰原子吸收光谱法进行镉镍电池陶瓷绝缘子镀液中锌、铜、铁含量的连续测定。在优化条件下.该方法灵敏度高,干扰小,选择性和重现性好,步骤简单,操作容易,分析周期短。测定结果的相对标准偏差均小于1.0%,加标回收率为97.0%~99.0%。该法适用于镉镍电池陶瓷绝缘子镀液中锌、铜、铁含量的现场控制分析和样品系统分析。  相似文献   

5.
火焰原子吸收光谱法测定20型尼龙毡材料中的铁   总被引:2,自引:1,他引:1  
采用空气-乙炔火焰原子吸收光谱法测定镍镉电池尼龙毡材料中的铁含量,对测定条件和干扰因素进行了综合分析。铁的浓度在0.0~5.0μg/mL内与吸光度成线性关系,相关系数为0.9998。测定尼龙毡样品铁含量的相对标准偏差不大于1.0%(n=8),标准加入回收率为97.0%~98.0%。该法适用于镍镉电池尼龙毡中铁含量的控制分析。  相似文献   

6.
正对锂离子电池、镍氢电池和镍镉电池等二次电池废料中的金属资源进行回收再生利用,不仅能够满足再生利用行业的发展需求,而且能避免这些金属对环境的潜在危害作用~([1-5])。镍是二次电池废料中含量较多的有价金属,其质量分数一般不高于70%~([6-7])。在回收二次电池废料中镍时,镍含量的准确测定非常关键,但关于此方面的研究却鲜有报道。  相似文献   

7.
镉镍电池和氢镍电池同以镍电极作正极,但两者的充、放电过程,特别是过充、过放时所表现的特性存在诸多差异,我们比较、探讨了影响这两种电池性能的差异因素,并由此制定了改进电池性能的有效工艺生产措施.  相似文献   

8.
研究了疏水性离子液体[Emim] PF_6-邻菲咯琳萃取体系对废旧镍镉电池中镉、镍离子的萃取性能,考察了振荡时间、温度、平衡水相酸度和萃取剂用量时萃取性能的影响.在水相pH值为5.91、温度为80℃时,4.0mL4g/L的邻菲咯琳与3.0mL离子液[Emim] PF_6组成的萃取体系时废旧电池液中镉、镍离子萃取效果良好.同时研究了废旧离子液在不同时间及酸度下的反萃效果,在浓度为1.0mol/L的盐酸介质中反萃1h,镉、镍离子能较好地被反萃.  相似文献   

9.
废水中痕量镉,镍的富集及测定   总被引:4,自引:0,他引:4  
废水中痕量镉、镍的富集及测定刘春明田尚衣*蒋桂华李红玫(长春师范学院化学系长春130032)关键词液膜镉镍电感耦合等离子体原子发射光谱(ICP-AES)中图分类号O657.31镍、镉等金属广泛用于电镀、电解及电池生产,属于危害人体健康的有毒元素。因此...  相似文献   

10.
原子吸收光谱法测定镉镍电池浸渍液中硅   总被引:1,自引:0,他引:1  
提出用一氧化二氮-乙炔火焰原子吸收光谱法测定镉镍电池浸渍液中硅含量。方法具有良好的灵敏度,干扰少,重现性好。硅量在5-50μg/mL范围内与吸光度呈良好的线性关系。其相对标准偏差均为1.0%;标准加入回收率在97.0%-103.0%范围内,适用于镉镍电池浸渍液中硅的分析。完全达到了实验室分析质量控制的要求。  相似文献   

11.
The distillation behaviour of cadmium at a reduced pressure was investigated to develop an actinide recovery process from a liquid cadmium cathode in a laboratory scale cadmium distiller. The apparent evaporation rate of cadmium increased with an increasing temperature whereas the rate decreased with an increasing vacuum pressure. The evaporation rate of cadmium varied within 9.7–40 g/cm2/h in the temperature range of 500–650 °C and pressure range of 0.5–10 Torr (0.0667–1.33 kPa). The theoretical values calculated by the Hertz–Langmuir relation were much higher than experimentally measured values. The deviation was compensated by an evaporation coefficient (α) obtained empirically. About 0.02–0.20 wt% of residue was left in the crucible after distillation and found to be CdO. It could be concluded that the temperature range of 500–650 °C is favourable for the cadmium distillation process if residual eutectic salt does not exist in the cadmium alloy surface.  相似文献   

12.
多相条件下亚硫酸镁非催化氧化反应动力学及机理   总被引:2,自引:0,他引:2  
副产物的氧化回收利用是影响镁法脱硫工艺发展的关键.本文通过真空旋转蒸发的方式制备了高纯度的亚硫酸镁样品,并利用鼓泡式反应装置,研究了亚硫酸镁非催化氧化的反应动力学,考察了pH、氧分压、亚硫酸镁浓度、气体流量、温度等因素对亚硫酸镁氧化反应速率的影响,得到了各反应物的分级数及表观活化能.结合三相反应过程的数学模型推断出亚硫酸镁氧化的本征反应在慢反应区进行,且氧的传质扩散是总反应的速率控制步骤.研究结果为氧化回收镁法脱硫副产物提供了理论依据.  相似文献   

13.
A new separation method, negative pressure cavitation (NPC) extraction followed by HPLC‐MS‐MS for the determination of paclitaxel and its analogues in the needles of Taxus species is described in this study. Compared with three conventional extraction methods, NPC is a more effective, economical, and facile method for the separation of nature compounds from herbal plants. In contrast to high‐temperature extraction, NPC at low temperature can minimize undesirable reactions such as thermal decomposition or degradation. In addition, the extraction mechanism of NPC was also illuminated. The effects of vacuum degree, extraction solvent, ratio of solid to liquid, time, and times extraction were studied and optimized. The optimum extraction conditions were as follows: vacuum degree –0.03 MPa, solvent 80% v/v alcohol, ratio of material to liquid 1:15 (g/mL), extraction time 60 min, extraction (×3). Using these conditions, the recoveries of 10‐deacetyl‐7‐xylosylpaclitaxel, 10‐deacetylpaclitaxel, cephalomannine, and paclitaxel were higher than 95.88, 95.82, 94.85, and 96.18%, respectively. The contents of paclitaxel, 10‐deacetyl‐7‐xylosylpaclitaxel, 10‐deacetylpaclitaxel, and cephalomannine for Taxus chinensis were 0.0053, 0.0467, 0.0132, and 0.0076%, and 0.0067, 0.0153, 0.0047, and 0.0064% for Taxus cuspidata, respectively. Furthermore, a comparison of SEM images observed the morphological changes of microstructures and cellular damage in yew needles.  相似文献   

14.
An alternate pumping-recycle system utilizing a commercially available low dead-volume switching valve was developed for microcolumn LC. The recycle system had two separation columns, and the dead volume of the recycling lines was kept to a minimum by avoiding passage of the sample through the pump chamber, sample injector, and the normal path length of a conventional UV detector. The drawback of the high total back pressure caused by the second column that is placed after the detector was overcome by on-column detection, and this eliminated the need for a high pressure flow cell. The system was used for the separation of an authentic mixture of benzene, benzene-1,3,5-d3, and benzene-d6. Baseline separation was accomplished after six cycles and the calculated theoretical plate number for benzene was 230,000. It was observed that the theoretical plate number (N) increased linearly with increasing number of cycles, and the N per unit time increased with increasing inlet pressure. The separation conditions were optimized and the separation of benzene and benzene-d6 was accomplished within 75 min at 2.5 MPa inlet pressure.  相似文献   

15.
Commercial gas separation plants running adsorption processes, including pressure swing adsorption, vacuum pressure swing adsorption and temperature swing adsorption are intended to operate continuously and meet design performance levels over the complete service life of the facility. Performance degradation of the adsorbent materials in extended commercial usage is a common problem. Issues such as adsorbent aging and poisoning by unwanted or unexpected contaminants, represent some of the causes of declining adsorbent performance. Lower adsorption capacity can result in declining productivity and/or product purity for the gas separation plant. Adsorbent troubleshooting is usually accomplished by taking samples from the plant and sending them to off-site laboratories for analyses such as moisture content determination by Karl Fischer titration, or BET surface area or other adsorption capacity measurements. The turnaround time for these laboratory analyses is on the order of days. To short-cut this lengthy process of analysis, we have developed a simple test method and kit for rapid diagnosis of adsorbent performance issues which can be used directly at a plant site. The test method involves the determination of the gas capacity of an adsorbent by equilibrating the adsorbent with an appropriate test gas, deactivating the adsorbent and measuring the amount of test gas released. Once a sample has been acquired, the test can be executed and results obtained in less than 15 min. We show that the test method is accurate to within 5 % of the adsorption capacity determined from isotherm measurements, at equivalent temperature and pressure, and can be used to test common commercial adsorbent types, including low silica zeolites and activated carbons.  相似文献   

16.
The adsorption of copper(II), zinc(II), nickel(II), lead(II), and cadmium(II) on Amberlite IR-120 synthetic sulfonated resin has been studied at different pH and temperatures by batch process. The effects of parameters such as amount of resin, resin contact time, pH, and temperature on the ion exchange separation have been investigated. For the determination of the adsorption behavior of the resin, the adsorption isotherms of metal ions have also been studied. The concentrations of metal ions have been measured by batch techniques and with AAS analysis. Adsorption analysis results obtained at various concentrations showed that the adsorption pattern on the resin followed Freundlich isotherms. Here we report the method that is applied for the sorption/separation of some toxic metals from their solutions.  相似文献   

17.
Zhang L  Yin X  Fang Z 《Lab on a chip》2006,6(2):258-264
A simple method for injecting well-defined non-biased sample plugs into the separation channel of a microfluidic chip-based capillary electrophoresis system was developed by a combination of flows generated by negative pressure, electrokinetic and hydrostatic forces. This was achieved by using only a single syringe pump and a single voltage supply at constant voltage. In the loading step, a partial vacuum in the headspace of a sealed sample waste reservoir was produced using a syringe pump equipped with a 3-way valve. Almost instantaneously, sample was drawn from the sample reservoir across the injection intersection to the sample waste reservoir by negative pressure. Simultaneously, buffer flow from the remaining two buffer reservoirs pinched the sample flow to form a well-defined sample plug at the channel intersection. In the subsequent separation stage, the vacuum in headspace of the sample waste reservoir was released to terminate all flows generated by negative pressure, and the sample plug at the channel intersection was electrokinetically injected into the separation channel under the potential applied along the separation channel. The liquid levels of the four reservoirs were optimized to prevent sample leakage during the separation stage. The approach considerably simplified the operations and equipment for pinched injection in chip-based CE, and improved the throughput. Migration time precisions of 3.3 and 1.5% RSD for rhodamine123 (Rh123) and fluorescein sodium (Flu) in the separation of a mixture of Flu and Rh123 were obtained for 56 consecutive determinations with peak height precisions of 6.2% and 4.4% RSD for Rh123 and Flu, respectively.  相似文献   

18.
Uranium deposits were recovered at the solid cathode of an electrorefining system, and deposited uranium dendrite normally contains about 30–40 wt% LiCl–KCl eutectic salts. Therefore, a separation of the eutectic salts from deposited uranium is essential for reusing these salts and uranium. A process such as distillation was employed for cathode processing due to the advantages of a minimal generation of secondary waste, a compact unit process, and simple and low-cost equipment. However, the realization of a wide evaporation area or high distillation temperature is limited by various factors such as the material or structure of a distiller. Also, the electrical energy flow from outside has a lot of consumption to maintain the high temperature. Hence, in this study, solid–liquid separation experiments are proposed to increase the throughput of the salt removal process by the separation of the liquid salt prior to the distillation of the LiCl–KCl eutectic salt. The solid–liquid separation of salt was carried out in a vertical type distiller. The behavior of the solid–liquid separation of pure eutectic salt was investigated as a function of temperature, pressure, sieve size, and crucible shape. From the experimental results using pure eutectic salts, the amount of salt separation was achieved at more than 94 wt%. The rate of solid–liquid separation of salt using 600 °C is higher than that of 500 °C under the same condition. The influence of a vacuum for solid–liquid separation can be disregarded, and the separation rate of a 100 mesh was higher than that of a 150 mesh. In addition, the rate of separation for salts using a porous crucible is higher than that in a non-porous crucible.  相似文献   

19.
The space–time dynamics of absorbing atomic layers of cadmium and lead and molecular layers of zinc chloride in a commercially produced transverse-heated graphite atomizer and a newly developed two-step atomizer was studied. It was shown that the limiting temperature of cadmium pyrolysis in the two-step atomizer without the use of modifiers may be as high as 1000°C, whereas in the commercial analyzer is it not higher than 300°C. Levels of nonselective absorption due to sodium chloride were compared. It was found that, for a two-step atomizer, the maximum allowable mass of sodium chloride for which the background at lead and cadmium lines can be adequately compensated is 17–30 times higher than that for the commercial atomizer. The atomization of cadmium in the presence of sodium chloride was studied using time, space, and spectral resolution. It was shown that the effect of the chloride matrix in the two-step atomizer is suppressed because of sample fractionation and distillation in the course of its evaporation and condensation.  相似文献   

20.
Performance of continuous polymer enhanced ultrafiltration (PEUF) method was investigated for removal of mercury and cadmium from binary mixtures. This method includes the addition of polyethyleneimine (PEI) as a water soluble polymer to bind the metals, which was followed by ultrafiltration operation performed on both laboratory and pilot scale systems. The influence of various operating parameters such as temperature, metal/polymer ratio, presence of calcium ions and pH on retention of metals and permeate flux was investigated. To investigate the possibility of selective separation of mercury and cadmium, experiments were conducted for binary solutions at different pH and loading ratios. It was seen that the retention of mercury decreased and permeate flux increased when the temperature increased. The increased pH and decreased metal/polymer ratio, loading (L), resulted in higher retention of both metals. Shapes of retention vs. pH or L curves were very similar for both metals. Retentions stay almost constant at a value very close to unity until a critical L or pH value was reached, then, R decreases almost linearly with L or pH. However, retention of cadmium was affected more than that of mercury as the pH decreased and L increased. This leads to the selective separation of mercury and cadmium. At low pH values (about 5) and at high L values (about 0.3), mercury was removed by ultrafiltration operation while almost all cadmium passed through the membrane. At pH 5.5 and cadmium/polymer ratio about 0.35 and mercury/polymer ratio about 0.39, the highest separation factor was obtained as 49.  相似文献   

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