改性粉煤灰吸附含铬废水中Cr(Ⅵ)和Cr(Ⅲ)试验研究

针对铬渣淋滤液这类高质量浓度含铬废水,采用室内静态试验方法,进行了改性粉煤灰吸附含铬废水中Cr(Ⅵ)和Cr(Ⅲ)试验研究。结果表明,1 mol/L聚合氯化铝改性后的粉煤灰对铬吸附效果最佳;Cr(Ⅵ)质量浓度100 mg/L、Cr(Ⅲ)质量浓度25 mg/L的200 m L含铬废水最佳反应条件为:粉煤灰投加量50 g,反应时间60 min,p H值5.5,反应温度25℃,振荡速度200 r/min,对应Cr(Ⅵ)去除率达到80.2%,Cr(Ⅲ)去除率达到99.3%。     

天然生物材料吸附处理含Cr废水的研究

以柚子皮作为吸附剂,采用模拟含Cr废水进行实验,并通过脱色改性,单因素实验以及在共存离子情况下吸附处理实验,对吸附剂进行性能测试与分析;采用了吸附等温模型和吸附动力学模型以及热力学模型进一步分析其吸附机理。经过实验总结出最合适的反应条件:初始浓度为0.6 mg/L,pH为2,投加量为2 g/L,反应时间为60 min,温度为25℃,此时Cr的去除率达到99.70%。对吸附Cr~(6+)进行了吸附等温模型和吸附动力学模型拟合分析,结果表示Freundlich模型可以更好描述Cr~(6+)吸附数据。柚子皮对Cr~(6+)的吸附更适合用Ho准二级动力学模型来描述其吸附过程,温度有助于推动反应正向进行。     

碱溶粉煤灰对废水中六价铬的吸附试验研究

用氢氧化钠溶液对粉煤灰进行碱溶处理,并通过粉末X射线衍射光谱(XRD)和扫描电子显微镜(SEM)对碱溶前后粉煤灰的物质组成和形貌进行表征,研究了粉煤灰和碱溶粉煤灰对废水中六价铬(Cr6+)的吸附性能.试验结果表明:碱溶粉煤灰结构松散,同时含有大量沸石分子筛的晶体结构;碱溶粉煤灰对废水中Cr6+吸附容量大于普通粉煤灰,在碱溶粉煤灰质量浓度为15 g/L,反应时间30 min,pH值为5～6,反应温度在25～35 ℃时,碱溶粉煤灰对质量浓度50 mg/L的含Cr6+废水去除率可达88.56%,其吸附模型符合Langmuir模型,最大吸附容量达23.59 mg/g,吸附强度为0.043 5 L/mg.碱溶粉煤灰对废水中Cr6+的吸附是粉煤灰组分和新生的沸石分子筛组分共同作用的结果.     

微波联合碱改性粉煤灰对铬(Ⅵ)的吸附性能

为了强化改性粉煤灰在重金属废水处理中的吸附效果,利用微波联合碱改性的方法,研究微波温度、微波时间、微波功率等制备条件对改性粉煤灰吸附铬(Ⅵ)的影响以及吸附等温特性。结果表明,粉煤灰改性的最佳制备条件为:微波功率600 W,微波温度60℃,微波时间15 min,吸附量达到0.341 mg/g,较改性前提高50%以上。此改性条件下的粉煤灰进行吸附等温的试验研究结果表明,其对铬(Ⅵ)的吸附符合Freundlich和Langmuir等温吸附模型,此吸附过程为单分子层吸附。粉煤灰具有较高的经济性,可广泛用于含铬(Ⅵ)废水的处理。      

粉煤灰和C3N4复合材料对含铬废水的处理

粉煤灰是中国主要的工业废弃物之一,粉煤灰是一种多孔性、具有较大比较面积的固体颗粒,具有一定的吸附能力,可用于重金属的处理,起到以废制废的效果。C_3N_4作为一种非金属可见光响应新型的光催化剂,在光催化研究方面广泛用于降解重金属废水。本文通过研磨混匀处理制成粉煤灰和C_3N_4的复合材料。单因素试验使用粉煤灰和C_3N_4复合材料处理含铬废水,并对操作条件进行选择和优化,单因素试验结果表明,当粉煤灰和C_3N_4投加量40g/L,pH值2,吸附时间40 min,吸附剂配比为C_3N_4含量为5%的条件下,Cr6+去除率可达89.2%。对比试验发现粉煤灰和C_3N_4复合材料的去除效果优于纯粉煤灰。碱改性粉煤灰的去除率能达到92%以上,而粉煤灰和C_3N_4复合材料的去除率略低于90%,进一步研究考虑使用其他方式制备复合材料。     

PDMDAAC改性粉煤灰吸附处理含Cr(VI)废水的试验研究

本文用改性粉煤灰处理模拟含铬废水。实验结果表明:废水pH值在10以上,改性粉煤灰用量为20g/L;吸附平衡时间60min;反应温度为35～40℃,去除率可达98%以上。改性粉煤灰对Cr(VI)的吸附符合Langmuir模型。该方法具有处理效果好,操作简单,运行费用低等优点。     

PDMDAAC改性粉煤灰吸附处理含Cr(Ⅵ)废水的试验研究

本文用改性粉煤灰处理模拟含铬废水.实验结果表明:废水pH值在10以上,改性粉煤灰用量为20g/L,吸附平衡时间60min;反应温度为35～40℃,去除率可达98%以上.改性粉煤灰对Cr(Ⅵ)的吸附符合Langmuir模型.该方法具有处理效果好,操作简单,运行费用低等优点.     

改性粉煤灰处理废水中铬(Ⅵ)的研究

酸改性粉煤灰较粉煤灰对废水中的铬(Ⅵ)有较大吸附性。实验结果表明,改性粉煤灰处理含铬(Ⅵ)废水的最佳吸附条件:改性粉煤灰0.6 g、初始浓度10μg/mL、吸附时间25 min、pH=2~4、吸附温度20℃~30℃,最佳条件下改性粉煤灰对铬(Ⅵ)有较好的去除效果,去除率达96.5%。改性粉煤灰对铬(Ⅵ)的吸附以物理吸附为主,符合Freundlich等温吸附式。     

TBAB改性粉煤灰处理印染废水的实验研究

用TBAB(四丁基溴化铵)对粉煤灰进行改性后对印染废水进行脱色处理。以印染废水中存在的活性艳红为处理目标,通过一系列试验,确定较优的改性条件和脱色处理条件。试验结果表明,在TBAB浓度为2.0 g/L,粉煤灰浓度为3.5 g/L,溶液pH为2,吸附时间为1 h时,脱色率可达到最高,为91.3%。     

粉煤灰合成沸石吸附含铬废水中3价铬的研究

为解决高浓度含铬废水带来的危害,采用室内静态试验方法,利用粉煤灰合成沸石作为吸附剂对含铬废水进行吸附试验研究。试验结果表明,粉煤灰合成沸石对初始质量浓度100mg/L,pH值9.07的含3价铬废水,在投加量为15g、吸附时间为60min时,处理效果最佳,去除率可达99.62%,pH值适应范围为6.0~10.0。研究结果为工业企业处理高浓度含3价铬废水提供可靠的实验参数。     

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     

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     

2014 second batch of rare earth quota released

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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