H_3PW_(12)O_(40)-Fe_2O_3/膨润土的制备及其可见光-Fenton降解金橙Ⅱ

以机械活化预处理的Fe_2O_3/膨润土为载体,由等体积浸渍具有可见光响应活性的H_3PW_(12)O_(40),制得可见光-Fenton催化用H_3PW_(12)O_(40)-Fe_2O_3/膨润土催化剂。通过考察H_3PW_(12)O_(40)浸渍负载量、浸渍时间、焙烧温度、焙烧时间对H_3PW_(12)O_(40)-Fe_2O_3/膨润土催化性能的影响,确定最佳的制备工艺条件为:H_3PW_(12)O_(40)浸渍负载量20%、浸渍时间60 min、焙烧温度350℃、焙烧时间150 min。H_3PW_(12)O_(40)有效提高了所制备催化剂的可见光-Fenton反应催化活性,对金橙Ⅱ的催化降解在150 min时达到反应平衡,去除率为87.2%。金橙Ⅱ的H_3PW_(12)O_(40)-Fe_2O_3/膨润土可见光-Fenton催化反应符合一级动力学模型,速率常数k为0.0141 min-1。     

臭氧催化剂对煤化工高盐废水有机物去除性能研究

基于臭氧催化氧化技术在煤化工高盐废水处理上具有广泛的应用前景,为确定最佳臭氧催化剂及优化试验工艺参数,对催化剂制备工艺、载体及活性组分类型对COD去除率的影响进行研究,以确定催化剂制备工艺及最佳催化剂。采集宁夏某煤化工高盐废水开展工艺条件优化实验确定最佳工艺参数,最后对催化剂进行稳定性能评价及反应动力学研究。结果表明：废水中难降解有机物主要为含氮有机化合物;浸渍法催化效果优于混合法;活性氧化铝催化效果优于陶粒;活性组分铈催化效果优于锰和铁;最佳工艺条件：催化剂投加量1.0 L/L废水,臭氧投加量200 mg/L;臭氧催化剂反应70 h, COD去除率稳定在47%～50%;出水COD含量稳定在230 mg/L～245 mg/L,即臭氧催化剂具有足够的催化稳定性,通过臭氧催化氧化反应动力学研究发现催化剂的反应速率常数大于纯臭氧氧化,即臭氧催化氧化工艺可有效降解水中有机物,提高COD去除率。     

硅藻土负载铁氧化物催化剂的制备及其对某选矿废水的降解试验

某硫铁矿选矿废水COD偏高,达220 mg/L,通过将铁氧化物负载于硅藻土上制成非均相Fenton法催化剂,用于对该废水进行氧化处理。试验结果表明:非均相Fenton法催化剂适宜的制备条件为Fe3+浓度0.03 mol/L,Na OH与Fe3+的物质的量之比3,焙烧温度150℃;新型硅藻土负载铁氧化物催化剂非均相Fenton法降解废水COD的工艺条件为废水初始p H=5,催化剂投加量为1.5 g/L,H2O2投加量为11.79 mmol/L,反应时间为60 min,废水的COD去除率达85.67%;以资源丰富、负载性能好的硅藻土为原料制备的非均相Fenton法催化剂,可高效、低成本降解选矿废水的COD,处理后的水质符合排放标准,具有工业应用价值。     

粉煤灰负载Fe2+/Cu2+非均相催化H2O2降解甲基橙研究

通过溶液浸渍法成功制备粉煤灰负载Fe2+/Cu2+催化剂,利用XRD、XRF和FTIR等对组成和结构进行表征,研究pH值、反应温度、H2O2质量浓度及催化剂用量等对甲基橙降解效果的影响。结果表明：粉煤灰负载型催化剂的活性组分由粉煤灰本身所含铁,以及浸渍过程中吸附和表面残留的铜、亚铁离子组成。负载型催化剂对甲基橙降解具有较宽的pH值范围,良好的降解效果,对于1 g/L的甲基橙溶液,当催化剂用量为1 g/L,pH值为4,反应温度为50℃,H2O2质量浓度为33.3 g/L,搅拌时间为20 min,甲基橙的降解率接近100%。     

蒙脱土负载TiO_2光催化降解苯酚性能研究

采用溶胶-凝胶法制备TiO_2/MMT光催化复合材料,考察TiO_2负载量、焙烧温度和时间、p H值、苯酚溶液初始质量浓度、MMT添加量对光催化降解苯酚活性的影响。结果表明,TiO_2负载量为60%,焙烧温度为500℃,焙烧时间为4 h,制备的TiO_2/MMT对苯酚降解活性最佳,在p H值为6,溶液初始质量浓度为10 mg/L,光催化剂用量为2 g/L条件下,对苯酚溶液光催化降解150 min降解率为86.1%。采用傅里叶红外光谱仪、X射线衍射仪、扫描电镜对复合材料进行表征。结果表明,TiO_2与MMT复合后均为锐钛矿相,粒径减小,60%TiO_2/MMT复合材料对苯酚的光催化降解活性优于纯TiO_2,降解过程遵循准一级动力学方程。     

Y-N-TiO_2/凹凸棒土光催化剂制备及性能研究

以钛酸丁酯为钛源、硝酸钇和二乙醇胺为改性剂原料,凹凸棒土为载体,采用溶胶-凝胶法制备了凹凸棒土负载的Y-N-TiO_2/凹凸棒土光催化剂,通过IR和XRD对其结构进行表征。考察了焙烧温度、催化剂用量、溶液pH值、光照条件等因素对光催化剂降解诺氟沙星性能的影响。结果表明,Y、N掺入了TiO_2晶格,其中部分TiO_2进入了催化剂载体凹凸棒土的层间并通过化学键与其成功复合。500℃焙烧的催化剂中锐钛矿型TiO_2比例相对较高,表现出最优的光催化活性,当催化剂用量为2g/L,溶液pH值为6,在可见光或太阳光下反应2h后,该催化剂对25mg/L的诺氟沙星降解率分别达89.6%和91.3%。此外,该催化剂易于回收,再生性良好。     

硅藻土负载纳米Fe_2O_3复合材料的光催化性能研究

本研究选择提纯后的硅藻土充当Fenton催化剂基础载体,采用水解沉淀法将纳米Fe_2O_3颗粒负载在硅藻壳体表面制备得到一种新型的非均相Fenton复合材料,以罗丹明B作为染料废水检验催化剂的催化性能,研究结果表明,在光照条件下加入硅藻土负载Fe_2O_3催化剂和H_2O_2,反应120 min后,罗丹明B的脱色率可达到98.33%。     

制备条件对煤热解制氢用NiO/γ-Al2O3催化剂活性影响的研究

文章介绍了一种负载型NiO/γ-Al2O3催化剂的制备,并且从Ni的负载量、焙烧时间、焙烧温度3个方面探讨了不同的制备条件对NiO/γ-Al2O3催化剂活性的影响.通过实验确定了NiO/γ-Al2O3催化剂制备的最佳工艺条件,应用XRD检测手段对催化剂的结构和性能进行了表征.结果表明:NiO/γ-Al2O3催化剂最佳的制备条件为Ni的负载量为10%、焙烧温度为450℃,焙烧时间为5h.     

Co改性Fe_2O_3/AC催化剂低温SCR脱硝性能

以活性炭(AC)为载体,铁、钴为活性组分,采用等体积浸渍法制备Fe_2O_3/AC催化剂和Co-Fe_2O_3/AC催化剂。探讨了铁含量和钴对催化剂低温脱硝性能的影响。结果表明,当铁负载量为10%时能够取得比其它负载量较佳的NO转化效率;由于铁的存在,钴添加后能够均匀分散在催化剂表面,提供了更多的催化活性位,从而改善了Fe_2O_3/AC催化剂的低温选择性催化还原(SCR)脱硝活性。当Co/Fe质量比为0.7时,催化剂表现出较佳的脱硝效果。     

改性A-TiO2紫外光催化降解碱性品红

以TiOSO₄为原料, 用水热法制备了掺铁TiO₂晶体粉末, 用XRD测定了样品的晶型, 研究了以自制的催化剂对碱性品红溶液的光催化降解行为。实验结果表明: 自制的掺铁TiO₂为锐钛矿型TiO₂(即A-TiO₂); 光催化降解碱性品红溶液的优化条件是: 2 mg/L的碱性品红溶液、掺铁量5%(摩尔分数)、A-TiO₂粉末加入量1.2 g/L, 室温搅拌下紫外(λ=365 nm)光照降解反应3 h, 此条件下碱性品红溶液降解率达到88.59%。     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

唐口煤矿深部复杂开采工作面瓦斯分源涌出规律研究

研究工作面瓦斯涌出规律对工作面瓦斯治理有重要意义。为了得到唐口煤矿深部3号煤层复杂开采条件下工作面回采时期瓦斯涌出时空演化规律,选取6304工作面作为对象,采用实测方法研究6304工作面瓦斯涌出规律。结果表明:6304工作面瓦斯涌出量为6.534 m³/min,其中煤壁占34.27%,落煤占29.62%,采空区占36.11%;沿工作面倾向由低到高,瓦斯浓度整体为上升趋势,其中1—76号架工作面瓦斯浓度小于0.20%,76—102号架瓦斯浓度上升明显,最大为0.387%;上隅角的后部采空区是工作面的瓦斯主要涌出源,上隅角1号测点瓦斯浓度0.78%,上隅角周边3号、5号、7号、8号、9号测点瓦斯浓度平均为0.643%;周期来压时,上隅角瓦斯相对平时较高。研究为针对性的瓦斯分源监控与灾害防治提供基础。