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1.
用废旧电路板酸浸-电沉积法回收金属铜   总被引:1,自引:0,他引:1  
为了既保障环保又达到最佳铜回收效果的目的,以废旧电路板经过初步破碎分离,得到铜金属富集产品为研究对象,采用硫酸-双氧水浸出结合电沉积工艺回收物料中的铜。考察了铜浸出率与硫酸质量浓度、双氧水用量、浸出时间、液固比之间的关系,进行最佳金属浸出条件实验。结果表明:硫酸物质的量浓度为3.5 mol/L、浸出时间3 h、双氧水用量为20 mL、液固比10∶1条件下,铜金属浸出率最高可达到97.58%。电沉积尾液循环用以浸出铜,铜离子循环质量浓度不低于18 g/L,平均电流效率高于97.60%。在沉积温度40℃,阴极材料为T2紫铜,电流密度小于800 A/m2时,电流效率可以保持在97%以上。实验中铜回收率达到了97.58%。  相似文献   

2.
对闪锌矿还原氯酸钠制备二氧化氯的反应过程进行了研究 ,得出反应的最佳条件 :反应体系中硫酸的浓度须维持在 2 .5~ 3 .0 mol/ L,闪锌矿过量率为 2 %~ 4 % ,温度为 60℃左右 ,氯酸钠初始浓度为 4~ 5mol/ L.该法具有反应温和、易于控制、硫酸消耗少、成本低廉和产品纯度高的优点  相似文献   

3.
采用逐级优化的单因素实验考察钛硅-1分子筛(TS-1)催化丙酮氨氧化合成丙酮肟的反应条件.结果表明:催化剂用量、氨酮摩尔比、氧酮摩尔比、氨水及双氧水滴加时间、氨水及双氧水滴加组合模式、叔丁醇与水体积比及反应温度等因素对反应效果影响较显著.适宜的反应条件为:每mol丙酮催化剂用量4g以上,氨酮摩尔比2.0以上,氧酮摩尔比1.0~1.4,氨水及双氧水滴加时间不小于1 h,且同时滴加完毕,后续反应时间不小于1h,V(叔丁醇)/V(水)=2.3,反应温度70 ℃.在此优化反应条件下,丙酮转化率可达95%,丙酮肟选择性为98%.  相似文献   

4.
高效、高纯稳定二氧化氯溶液生产技术关键因素的优化   总被引:2,自引:0,他引:2  
采用DTJ HP法制备高效、高纯稳定二氧化氯溶液,考察了反应温度、催化剂种类、双氧水用量、硫酸用量和反应压力等对二氧化氯反应收率的影响,采用正交试验确定了较理想的反应条件:反应温度为40℃,压力为-0.4MPa;催化剂采用复合催化剂B,其用量为1.5g;双氧水用量为150mL;硫酸用量为190mL。在较理想的反应条件下,二氧化氯反应收率为85.6%。  相似文献   

5.
淀粉还原氯酸钠制备二氧化氯的研究   总被引:2,自引:0,他引:2  
以淀粉、氯酸钠、硫酸为原料,在投料比(物质的量比)n氯酸钠:n淀粉为24:1.5、硫酸浓度为5mol/L、反应温度为90℃、反应时间为95min的条件下,二氧化氯的产率可达94%,纯度达96%以上,结果表明,淀粉还原氯酸钠是制备二氧化氯的一种新途径。  相似文献   

6.
本文以硬脂酸和氢氧化钙为原料,双氧水和乙醇为复合催化剂,实现了在水介质中绿色清洁合成硬脂酸钙.考察了双氧水用量、乙醇用量、反应温度、固液比和反应时间等因素对反应的影响.结果表明,在双氧水用量24%、乙醇用量10%、反应温度60℃、固液比1∶15、反应时间3 h的优化条件下,产品的游离酸含量为0.28%.生产后的滤液可进行重复使用,避免了废水的排放.工业放大实验结果表明,此方法可沿用现有复分解法设备进行工业化生产.  相似文献   

7.
对闪锌矿还原氯酸钠制备二氧化氯的反应过程进行了,得出反应的最佳条件:反应体系中硫酸的浓度须维持在2.5-3.0mol/L,闪锌矿过量率为2%-4%,温度为60℃左右,氯酸钠初始浓度为4-5mol/L,该法具有反应温和、易于控制、硫酸消耗少、成本低廉和产品度高的优点。  相似文献   

8.
探讨了以乙醇、氯酸钠、硫酸为原料制备二氧化氯,通过正交实验研究了影响二氧化氯产率和纯度的因素,即物料的配比、酸度和温度,得出了最佳工艺条件:在投料比(物质的量比)n氯酸钠∶n乙醇为4∶1.5,硫酸的浓度为6mol/L,反应温度为55℃,反应时间为35min的条件下,二氧化氯的产率可达93%,纯度达94%。本文在一定程度上拓展了二氧化氯制备的思路。  相似文献   

9.
探讨了以乙醇、氯酸钠、硫酸为原料制备二氧化氯,通过正交实验探讨了影响二氧化氯产率和纯度的因素,即物料的配比、酸度和温度,得出了最佳工艺条件:在投料比(物质的量比)n氯酸钠∶n乙醇为4∶1.5,硫酸的浓度为6 mol/L,反应温度为55 ℃,反应时间为35 min的条件下, 二氧化氯的产率可达93 %,纯度达94 %。该文在一定程度上拓展了二氧化氯制备的思路。
  相似文献   

10.
在常压下,以高锰酸钾为原料,与双氧水以及一定沉淀剂的反应来制取二氧化锰.以静态坩埚燃烧法,考察了不同沉淀剂、焙烧温度、反应温度、反应物配比对二氧化锰助燃性能的影响规律.结果表明:在反应中选取碳酸氢铵为沉淀剂时,氧化锰的助燃效率最高;随着氧化锰的焙烧温度以及反应温度的升高,氧化锰的助燃效率呈增大趋势;双氧水的用量也使氧化锰的性能发生变化,随着双氧水用量的增加,氧化锰的助燃性能也随之提高.二氧化锰最佳制备条件为:以0.05mol的高锰酸钾溶液为基准,30%的双氧水50mL,0.25mol/L的碳酸氢铵20mL,在50℃的水浴中反应3h,焙烧温度为500℃,此时二氧化锰使煤的燃烧效率提高了3%.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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