Uranium (VI) removal from aqueous solution using iron-carbon micro-electrolysis packing
作者：
Wu, Xiaoyan* ;Lv, Chunxue;Yu, Shoufu;Li, Mi;Ye, Jian;...
期刊：
Separation and Purification Technology ,2020年234:116104 ISSN：1383-5866
通讯作者：
Wu, Xiaoyan
作者机构：
[Yu, Shoufu; Li, Mi; Ye, Jian; Zhang, Xiaowen; Lv, Chunxue; Wu, Xiaoyan; Liu, Yong] Univ South China, Sch Resource & Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Ye, Jian; Zhang, Xiaowen; Wu, Xiaoyan] Univ South China, Hengyang Key Lab Soil Contaminat Control & Remedi, Hengyang 421001, Peoples R China.;[Li, Mi; Ye, Jian; Zhang, Xiaowen; Wu, Xiaoyan] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
通讯机构：
[Wu, Xiaoyan] U;Univ South China, Sch Resource & Environm & Safety Engn, Hengyang 421001, Peoples R China.
关键词：
Uranium-bearing wastewater;U(VI);Iron-carbon micro-electrolysis packing
摘要：
Iron-based materials have attracted much attention in water treatment because of excellent ability to treat pollutants. In this study, self-made iron-carbon micro-electrolysis packing (IMP) was introduced to treat uranium-bearing wastewater (UBW). The effects of the IMP dosage, initial pH of solution and initial U(VI) concentration was investigated. The comparison of material adsorption performance and repeated desorption experiments were also accomplished under the optimum conditions. The mechanism of treating UBW by IMP was revealed by studying the change of IMP's surface properties characterized before and after adsorption by Scanning Electron Microscope (SEM), Energy-Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS) and Mossbauer spectra (MS). Research results demonstrated that IMP is suitable for the treatment of UBW with low concentration at acid condition (pH < 5). SEM results indicated that uranium was deposited on the surface of IMP in the form of tidy fine particles. The most important reason for uranium removal was determined as the reduction of soluble U(VI) to insoluble U(IV) by IMP. The advantages of IMP for UBW treatment were verified with rapidity, high efficiency, and durability. Therefore, IMP could be considered as a positive material for uranium removal from UBW.
语种：
英文
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纳米矿晶处理含铀废水的效能与机理研究
作者：
于守富;刘永;吴晓燕;何鹏;张晓文;...
期刊：
化学工程 ,2020年48(1):12-17 ISSN：1005-9954
通讯作者：
Liu, Y.
作者机构：
南华大学资源环境与安全工程学院,湖南衡阳421001;南华大学湖南省铀尾矿库退役治理工程技术研究中心,湖南衡阳421001;南华大学衡阳市土壤污染控制与修复重点实验室,湖南衡阳421001;南华大学放射性三废处理与处置重点实验室,湖南衡阳421001;[刘永; 张晓文; 李密; 吴晓燕; 于守富; 吕春雪; 何鹏] 南华大学
通讯机构：
School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, China
关键词：
凹凸棒土;海泡石;纳米矿晶;吸附
摘要：
以凹凸棒土、海泡石、硅藻土等为原料制备了颗粒状的纳米矿晶(NMC)吸附剂,研究了NMC在不同pH值、NMC用量、吸附时间和铀离子(U(Ⅵ))初始质量浓度对U(Ⅵ)的去除效能的影响。通过扫描电镜、X射线能谱仪、红外光谱等检测手段解析了NMC吸附U(Ⅵ)的机理。研究结果表明:NMC适用于酸性条件下处理含铀废水。当含铀废水pH值、U(Ⅵ)质量浓度、NMC投加量分别为2.0,20.0 mg/L,30 ℃,7.0 g/L时,废水中U(Ⅵ)去除效率高达97.4%。NMC吸附U(Ⅵ)的过程以化学吸附为主,准二级吸附动力学模型相关系数R~2=0.991。扫描电镜和X射线能谱分析发现,U(Ⅵ)主要吸附在NMC的表面孔内;红外光谱分析结果表明配位、络合、离子交换也可能是NMC吸附U(Ⅵ)的机理,参与的主要基团有-OH,C=O,C-N,NH~+,C-H和Si-OH。
语种：
中文
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功能性纤维状二氧化硅纳米粒子的调控制备及在吸附分离中的应用
作者：
Huang, Qianwen;Zhang, Xiaowen;Li, Mi;Wu, Xiaoyan;Yuan, Liyong*
期刊：
化学进展 ,2020年32(2-3):230-238 ISSN：1005-281X
通讯作者：
Yuan, Liyong
作者机构：
[Huang, Qianwen; Yuan, Liyong] Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.;[Li, Mi; Huang, Qianwen; Zhang, Xiaowen; Wu, Xiaoyan] Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Yuan, Liyong] C;Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.
关键词：
纤维状二氧化硅;功能化;形貌调控;吸附;放射性核素
摘要：
利用吸附剂对环境中污染物进行分离去除是环境污染治理的有效方法和常用方法,其中以无机材料为载体的功能化吸附剂应用更为广泛。二氧化硅纳米颗粒具有稳定性好、易修饰、成本低和对环境友好等特点,在环境污染物的吸附分离方面具有广阔的应用前景。纤维状硅球与传统的二氧化硅纳米颗粒相比具有比表面积大、有开放孔道等优点,在实际吸附分离应用中能够提供更多有效吸附位点且孔道不易堵塞,是一种更具潜力的吸附剂载体。本文结合本课题组的研究工作对纤维状硅球的合成制备尤其是结构参数的调控方面进行了归纳分析;在分析近年来关于重金属、有机物、放射性核素等环境污染物处理相关研究的基础上,对功能性纤维状硅球在环境污染物吸附分离领域中的应用进行总结;最后从纤维状硅球合成方面的局限性以及应用方面的潜力对功能性纤维状硅球在吸附分离领域中的应用前景进行了展望。
语种：
中文
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工程教育认证背景下OBE教育理念的借鉴与思考
作者：
谭文发;周英;吕俊文;房琦;吴晓燕
期刊：
教育现代化 ,2019年(07):28-30 ISSN：2095-8420
作者机构：
1. 南华大学资源环境与安全工程学院;2. 南华大学船山学院
关键词：
工程教育认证;环境工程;人才培养
摘要：
环境工程专业的教育强调知识的应用性,注重培养学生分析问题、解决问题的能力。为促进工程教育的国际互认,环境工程专业工程教育认证势在必行。南华大学环境专业是在原核工业第六研究所通风辐射防护室等基础上发展而来的,特色鲜明。近年,南华大学环境工程专业基于 OBE（Outcome based education）教育模式,紧紧围绕学校"一基三实"中强调的"把人才培养做实","把服务社会做实"的学校发展思路,在培养目标分解、理论课程体系和实践教学改革、学生创新能力培养、评估体系完善和高素质教师队伍建设等方面进行了一系列的改革与尝试,取得了良好效果。
语种：
中文
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Adsorption of U(VI) ions from aqueous solution using nanogoethite powder
作者：
Zhang, Lijiang;Zhang, Xiaowen* ;Lu, Qian;Wu, Xiaoyan;Jiang, Tianjiao;...
期刊：
Adsorption Science & Technology ,2019年37(1-2):113-126 ISSN：0263-6174
通讯作者：
Zhang, Xiaowen
作者机构：
[Lu, Qian; Peng, Ying; Zhang, Lijiang; Zhang, Xiaowen; Jiang, Tianjiao; Wu, Xiaoyan; Mi, Li] Univ South China, Sch Resources Environm & Safety Engn, Hengyang, Peoples R China.;[Zhang, Xiaowen; Mi, Li] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang, Peoples R China.;[Zhang, Xiaowen] Univ South China, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Zhang, Xiaowen] U;Univ South China, Hengyang 421001, Hunan, Peoples R China.
关键词：
Uranium;chemical precipitation synthesis;nanogoethite;adsorption;iron oxide
摘要：
Goethite is a stable and widespread mineral present in soil with many uses, and it affects the transportation and immobilization of heavy metals in solution. Nanogoethite was synthesized by a chemical precipitation method and used to batch adsorb U(VI) in solution. Adsorption experiments were used to understand the role of nanogoethite in controlling the U(VI) adsorption behavior in soil. The morphology and the crystallinity of nanogoethite were characterized by scanning electron microscopy and wide-angle X-ray powder diffractometry, respectively. The results showed that the crystallinity of nanogoethite after the adsorption of uranium did not change, but small particles appeared on the surface of the scales. The surface area was determined from N 2 adsorption–desorption experiments using the Brunauer–Emmett–Teller to be 81.86 m 2 /g. The effects of factors such as the contact time, pH, adsorbent dosage, and the initial concentration of uranium on the adsorption of U(VI) were investigated. The experimental results showed that nanogoethite removed over 85% of the U(VI) in an aqueous 5.0 mg/L U(VI) solution at pH 4.0 and at 298 K. The pseudo-second-order model was used to simulate the adsorption process. The results show that chemisorption plays a major role in the adsorption process. The results of this study suggest that nanogoethite may play a significant role in controlling the migration and transfer of U(VI) in the soil, thus controlling the presence of U(VI) in soil. © The Author(s) 2019.
语种：
英文
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Understanding the solid phase chemical fractionation of uranium in soil profile near a hydrometallurgical factory
作者：
Yang, Sheng;Zhang, Xiaowen* ;Wu, Xiaoyan;Li, Mi;Zhang, Lijiang;...
期刊：
Chemosphere ,2019年236(Dec.):124392 ISSN：0045-6535
通讯作者：
Zhang, Xiaowen
作者机构：
[Li, Mi; Yang, Sheng; Peng, Ying; Zhang, Lijiang; Huang, Qianwen; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiaoyan] Univ South China, Sch Resource & Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiaoyan] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
通讯机构：
[Zhang, Xiaowen] U;Univ South China, Sch Resource & Environm & Safety Engn, Hengyang 421001, Peoples R China.
关键词：
Adsorption-migration;Sequential extraction;Soil profile;Spatial distribution;U
摘要：
Uranium (U) contamination of soil has become a major concern with respect to its toxicity, accumulation in the food chain, and persistence in the environment. Anthropogenic activities like mining and processing of U ores has become pressing issues throughout the world. The aim of the work is to understand the chemical fractionation of U in polluted soil and the mechanism involved. U-free soils samples of eluvial (E), illuvial (B), and parent-material (C) horizons from a hydrometallurgical factory area were used. The experimental results showed that the U adsorption capacity decreased with depth, and its mobility in the upper soil is better than the lower. It was closely related to distribution coefficient (Kd), pH, organic-matter (OM), and carbonate content of soil horizons. The chemical fractionation of U was studied using the BCR sequential extraction scheme for soils after saturated adsorption. It was noted that the U reducible and oxidizable fraction in the E and B horizons can vertically transfer to the C horizon and occurs a significant rearrangement of U in different horizons. BET, SEM, XRD, and FT-IR analyses showed that different U distribution and migration in soil profile is mainly affected by specific surface area, soil particle size, mineral composition, and active groups. The XPS data further indicated that U (VI) is gradually converted to U (IV) with decreased depth and fixed in deeper soil becoming insoluble and immobile. It is the first step to investigate potential migration and plan U mining and milling area long-term management. © 2019
语种：
英文
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《现代检测技术》课程教学新探索
作者：
吴晓燕;谭维;邓钦文;李密;房琦;...
期刊：
广东化工 ,2019年46(5):242,247 ISSN：1007-1865
作者机构：
南华大学 资源环境与安全工程学院,湖南衡阳,421001;南华大学 研究生院,湖南衡阳,421001;[张德; 李密; 邓钦文; 吴晓燕; 房琦; 谭维; 谭文发] 南华大学
关键词：
检测技术;环境工程;硕士研究生
摘要：
《现代检测技术》逐渐成为环境工程专业硕士研究生的重要专业课程,主要包括样品的预处理、仪器检测技术和结果表达分析等方面内容。针对研究生的培养目标,利用现代化的检测手段来检测环境问题中所涉及的相关重要指标,通过各类指标来分析与解决重大环境问题。结合现阶段研究生培养过程中存在的问题与不足,以及学校的特色,本文从教学内容、教学方式与考核方式三个方面来开展该门课程的教学新探索,以期为类似的教学提供一定的参考作用。
语种：
中文
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金属有机框架材料吸附分离水中铀的应用
作者：
彭莹;张晓文;李密;张宇;吴晓燕
期刊：
化工进展 ,2019年38(7):3227-3242 ISSN：1000-6613
通讯作者：
Zhang, Xiaowen(shawn_zhang@sina.com)
作者机构：
[彭莹; 张晓文; 李密; 张宇; 吴晓燕] College of Resources, Environment and Safety Engineering, University of South China, Hengyang;Hunan;421001, China;[彭莹; 张晓文; 李密; 张宇; 吴晓燕] Hunan;[彭莹; 张晓文; 李密; 张宇; 吴晓燕] 421001, China
关键词：
金属有机框架材料;吸附;水溶液;铀;稳定性;模拟
摘要：
金属有机框架材料（metal-organic frameworks,MOFs）具有极高的比表面积和孔隙率,结构可设计调控,但在水相吸附分离方面存在水稳定和选择吸附性较差、分离困难、合成与再生成本偏高等问题。针对MOFs的缺陷,可以通过有目的的功能化改性从而提升其对目标污染物的吸附性能。本文介绍了MOFs的结构优势,分析了水稳定性的影响因素和判断手段,简述了具有代表性的高水稳定性MOFs材料的特性;根据MOFs改性方法的分类回顾了MOFs及改性MOFs在去除水相中放射性铀的应用;基于不同分析技术探讨了MOFs与铀酰离子的吸附机理;提出推动MOFs在吸附铀方面规模化应用发展的核心是合成高稳定性MOFs,通过改性提高MOFs的选择吸附性能和再生性以及深入研究吸附机理。
语种：
中文
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某尾矿库附近各土壤层对U(VI)的吸附特性
作者：
杨升;张晓文;张利江;吴晓燕;李密;...
期刊：
环境工程学报 ,2019年13(10):2511-2520 ISSN：1673-9108
通讯作者：
Zhang, X.
作者机构：
[张利江; 黄倩文; 杨升] School of Resource & Environmental and Safety Engineering, University of South China, Hengyang, 421001, China;Key Laboratory of Radioactive Waste Treatment and Disposal, University of South China, Hengyang, 421001, China;[王亮] Hengyang Valin Steel Tube Co. Ltd., Hengyang, 421001, China;[张晓文; 李密; 吴晓燕] School of Resource & Environmental and Safety Engineering, University of South China, Hengyang, 421001, China, Key Laboratory of Radioactive Waste Treatment and Disposal, University of South China, Hengyang, 421001, China
通讯机构：
[Zhang, X.] S;School of Resource & Environmental and Safety Engineering, University of South China, Hengyang, China
关键词：
近地表处置;铀尾矿库;土壤剖面;静态吸附
摘要：
针对南方某铀尾矿库附近棕红壤剖面中的淋溶层、淀积层和母质层等土层对铀的吸附机理和空间分布规律进行了探讨。采用比表面测定、X射线荧光、扫描电镜、傅里叶变换和X射线衍射等方法对各土层样的理化性质、结构和形貌进行了表征分析;采用静态吸附法考查了时间、U(VI)初始浓度、pH、温度、粒径等因素对各土层吸附U(VI)的影响;并使用热力学和动力学方程对吸附过程进行了模拟分析。结果表明,25℃下淋溶层和淀积层pH均为6.2、母质层pH为4.1时,其对U(VI)最大吸附量分别可达23.60、22.82和13.05 mg·g~(-1)。热力学和动力学拟合结果分别表明,各土层对U(VI)更符合Langmuir方程(R~2>0.999)和准二级动力学模型(R~2>0.98)。风化程度,Fe、Mn、Al、Ca等元素及有机质含量,pH和土壤粒径等因素是各土层对U(VI)吸附能力不同的主要原因;同时,外源铀进入土壤剖面后,大部分聚集在土壤表层,随着深度的下降的铀含量也逐渐降低。研究结果可为土壤剖面中的铀和其他重金属的污染防治提供参考。
语种：
中文
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以MnFe_2O_4为阻挡层的Ni - YSZ 阳极支撑SOFC 的效能
作者：
吴晓燕;谭维;罗才武;张晓文;李密;...
期刊：
材料导报 ,2019年33(12):1949-1954 ISSN：1005-023X
作者机构：
南华大学资源环境与安全工程学院,衡阳,421001;南华大学研究生院,衡阳,421001;[罗才武; 张晓文; 李密; 吴晓燕; 房琦; 谭维; 谭文发] 南华大学
关键词：
固体氧化物燃料电池;阳极;阻挡层;铁酸锰;生物质气;积碳
摘要：
为提高镍-氧化钇稳定氧化锆(Ni-YSZ)阳极支撑的固体氧化物燃料电池(SOFC)以含碳气为燃料时的抗积碳性能,采用丝网印刷法在Ni-YSZ阳极表面印制阻挡层,阻挡层的材料为高温煅烧制备的铁酸锰(MnFe_2O_4)粉体。在750 ℃下以模拟污泥微波热解生物质气为燃料,测试含阻挡层的电池的电化学效能和抗积碳性能,并利用扫描电镜对测试前、后的阳极进行表征。研究结果表明:MnFe_2O_4阻挡层与Ni-YSZ 阳极的结合性较好;在Ni-YSZ 阳极上添加MnFe_2O_4阻挡层后,电池的放电性能有所降低,但是电池在以模拟生物质气为燃料时的抗积碳性能大幅提高,且在浆料中添加16%(质量分数)的石墨制备的阻挡层效果最佳。本研究对Ni-YSZ 阳极以生物质气为燃料时的抗积碳能力的改进与发展具有积极意义。
语种：
中文
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地方高校大学生环保意识与行为的对比研究——以南华大学环境工程专业为例
作者：
吴晓燕;谭维;李密;房琦;谭文发;...
期刊：
教育现代化 ,2019年(66):248-250 ISSN：2095-8420
作者机构：
1. 南华大学资源环境与安全工程学院;2. 南华大学研究生院
关键词：
环境工程;环保意识;环保行为
摘要：
本文的研究目的是开展环境工程专业与非环境工程专业学生在大学期间的环保意识与行为的对比研究。通过乐调查发布调查问卷的形式,调查研究了某高校环境工程专业大一至大四的全部学生,其中安全工程专业部分班级作为对照组。依据网站统计调查量表中的相关结果,被调研的所有大学生均有较高的环保意识,但环保行为较差。专业教育可较大提高学生的环保专业知识能力,但是对环保意识与环保行为的影响较小。高校需加强环保行为的活动开展和引导,以满足社会对大学生在环保各方面的期望。
语种：
中文
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3-甲基吡啶的微波液相法合成
作者：
罗才武;吴晓燕;张俊;徐怡菲;晁自胜
期刊：
合成化学 ,2018年26(2):127-130 ISSN：1005-1511
作者机构：
南华大学环境与安全工程学院, 湖南, 衡阳, 421001;南华大学核科学技术学院, 湖南, 衡阳, 421001;长沙理工大学材料科学与工程学院, 湖南, 长沙, 410114;[罗才武; 吴晓燕; 张俊] 南华大学环境与安全工程学院, 湖南, 衡阳, 421001;[徐怡菲] 南华大学核科学技术学院, 湖南, 衡阳, 421001
关键词：
微波液相法;3-甲基吡啶;甘油;二甲基亚砜;合成
摘要：
在液相条件下,采用微波协助合成3-甲基吡啶(1),其结构经GC-MS确证。研究了碳源(甘油、丙烯醛二甲缩醛和丙烯醛二乙缩醛)、氨源(硫酸亚铁铵、乙酸铵和氨水)、固体催化剂用量和溶剂(水、离子液体、二乙二醇甲醚、乙二醇丁醚和二甲基亚砜)对1合成反应的影响。结果表明:丙烯醛是重要的中间产物;在多相催化体系下,1收率最高可达到19.8%。
语种：
中文
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Immobilization of uranium into magnetite from aqueous solution by electrodepositing approach
作者：
Lu, Bing-qing;Li, Mi* ;Zhang, Xiao-wen;Huang, Chun-mei;Wu, Xiao-yan;...
期刊：
Journal of Hazardous Materials ,2018年343:255-265 ISSN：0304-3894
通讯作者：
Li, Mi
作者机构：
[Li, Mi; Lu, Bing-qing; Huang, Chun-mei; Fang, Qi; Zhang, Xiao-wen; Wu, Xiao-yan] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Fang, Qi; Zhang, Xiao-wen; Wu, Xiao-yan] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
通讯机构：
[Li, Mi] U;Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.
关键词：
Electrodeposition;Incorporation;Iron;Magnetite;Uranium
摘要：
Immobilization of uranium into magnetite (Fe<inf>3</inf>O<inf>4</inf>), which was generated from metallic iron by electrochemical method, was proposed to rapidly remove uranium from aqueous solution. The effects of electrochemical parameters such as electrode materials, voltage, electrode gap, reaction time and pH value on the crystallization of Fe<inf>3</inf>O<inf>4</inf>and uranium removal efficiencies were investigated. More than 90% uranium in the solution was precipitated with Fe<inf>3</inf>O<inf>4</inf>under laboratory conditions when uranium concentration range from 0.5 mg/L to 10 mg/L. The Fe<inf>3</inf>O<inf>4</inf>crystallization mechanism and immobilization of uranium was proved by XPS, XRD, TEM, FTIR and VSM methods. The results indicated that the cationic (including Fe<sup>2+</sup>, Fe<sup>3+</sup>and U(VI)) migrate to cathode side under the electric field and the uranium was incorporated or adsorbed by Fe<inf>3</inf>O<inf>4</inf>which was generated at cathode while the pH ranges between 2-7. The uranium-containing precipitate of Fe<inf>3</inf>O<inf>4</inf>can exist stably at the acid concentration below 60 g/L. Furthermore, the precipitate may be used as valuable resources for uranium or iron recycling, which resulted in no secondary pollution in the removal of uranium from aqueous solution. ©2017
语种：
英文
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Uranium Extraction from Tailings by Dilute Alkali Pretreatment-Sulfuric Acid Leaching Technology
作者：
Huang, Chunmei;Li, Mi* ;Zhang, Xiaowen;Gao, Fangying;Wu, Xiaoyan;...
期刊：
JOM ,2018年70(11):2746-2752 ISSN：1047-4838
通讯作者：
Li, Mi
作者机构：
[Li, Mi; Gao, Fangying; Fang, Qi; Huang, Chunmei; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiaoyan; Zhang, De] Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Fang, Qi; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiaoyan; Zhang, De] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
通讯机构：
[Li, Mi] U;Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.;Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
摘要：
Preliminary extraction research was carried out to develop a suitable dilute alkali pretreatment–sulfuric acid leaching process for uranium recovery from tailings containing 80 ppm uranium. The effects of alkali concentration, liquid-to-solid ratio, stirring speed and leaching time on uranium content in the leaching residues were investigated. The results showed that the leaching efficiency of dilute alkali pretreatment–sulfuric acid leaching is superior to direct acid leaching. Only 13 ppm and 7.5 ppm of uranium remained in tailings by using NaOH and Na 2 CO 3 , respectively, with an alkali concentration of 10 g/L, a liquid-to-solid ratio of 20, and an agitation of 400 rpm for 2 h. In addition, uranium liberation was significantly promoted by forming pores during the leaching process. This technology has advantages of low energy consumption, high leaching efficiency and less impurity production compared to traditional direct acid leaching. © 2018, The Minerals, Metals & Materials Society.
语种：
英文
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“以学生为主体”的环保设备设计课程教学与评分方案探究
作者：
张德;房琦;吴晓燕
期刊：
课程教育研究 ,2018年(40):230-231 ISSN：2095-3089
作者机构：
南华大学环境与安全工程学院环保设备工程系
关键词：
新工科;环保设备设计;探索性主题教学;考核评分
摘要：
新工科背景下的环保产业发展,亟需高等学校培养更具创新思维和实践能力的高级复合环保型人才。传统人才培养方式及评价系统难以满足当前我校环保设备工程人才的培养需求。本文在对传统教学模式及评分方法对环保设备设计课程的不适用性进行分析的基础上,提出'以学生为主体'的探索性主题教学方法,并制定了以课堂表现、主题探索学习、期末考核三部分成绩作为课程总体成绩的新型考核评分体系。以期更好地适应新工科人才培养需求,推动学科专业发展。
语种：
中文
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The treatment of U-containing wastewater by electro-deposition
作者：
Fangying Gao;Mi Li;Xiaowen Zhang;Shaoyan Lv;Xiaoyan Wu
作者机构：
[Fangying Gao; Mi Li; Xiaowen Zhang; Shaoyan Lv; Xiaoyan Wu] School of Environmental and Safety Engineering, University of South China
会议名称：
2nd International Conference on Material Science,Energy and Environmental Engineering(MSEEE 2018)
会议时间：
2018-08-16
会议地点：
中国陕西西安
摘要：
A new method for treating U-containing wastewater and recovering of uranium simultaneously by electro-deposition was proposed. The complexity of adsorbent preparation and difficulty in uranium recover
语种：
英文
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Extraction mechanism of depleted uranium exposure by dilute alkali pretreatment combined with acid leaching
作者：
Li, Mi* ;Huang, Chun-Mei;Zhang, Xiao-Wen;Gao, Fang-Ying;Wu, Xiao-Yan;...
期刊：
Hydrometallurgy ,2018年180:201-209 ISSN：0304-386X
通讯作者：
Li, Mi
作者机构：
[Gao, Fang-Ying; Li, Mi; Huang, Chun-Mei; Fang, Qi; Zhang, Xiao-Wen; Tan, Wen-Fa; Wu, Xiao-Yan; Zhang, De] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Zhang, Xiao-Wen; Wu, Xiao-Yan] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
通讯机构：
[Li, Mi] U;Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.
关键词：
Uranium;Tailings;Leaching;Gangue
摘要：
Uranium recovery from tailings is difficult because of the encapsulation of uranium by high content of gangue minerals. Uranium separation from gangue minerals has also been a key point in improving uranium extraction in the field of low-grade uranium resource recovery. This study proposed a high-efficiency alkali-pretreatment followed by acid leaching (two-step leaching) process for improving uranium extraction from uranium tailings. The main principle was to use a low concentration of alkaline solution to selectively comminute gangue minerals and to promote the formation of micropores in particles, providing a "path" for sulfuric acid to enter the interior of the uranium minerals. The effects of process parameters on uranium extraction and the changes in elemental composition, phase composition, morphology, and aperture of the tailings were investigated to show the mechanism of gangue comminution. Results showed that the uranium extraction percent without alkali pretreatment was only 63.91%, while it increased to 90.80% for the two-step leaching process under the same conditions. The low concentration of alkaline solution can selectively decompose gangue minerals, and dilute acid can then further reduce the degree of crystallinity of the silicates. Thus, a large number of mesopores in the tailings formed to improve the exposure ratio of uranium to the leaching agent. This new discovery may aid in the recovery of valuable metals from low-grade ore or tailings with high gangue content.
语种：
英文
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Optimization of demulsification-coagulation-adsorption parameters for the treatment of wastewater with fluorescent permeating agent from a Chinese machinery plant
作者：
Zhang, Xiaowen* ;Wang, Beibei* ;Wu, Xiao Yan;Li, Mi;Tan, Wenfa
期刊：
Desalination and Water Treatment ,2017年100:46-54 ISSN：1944-3994
通讯作者：
Zhang, Xiaowen;Wang, Beibei
作者机构：
[Li, Mi; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiao Yan; Wang, Beibei] Univ South China, Sch Environm & Safety Engn, Hengyang, Hunan, Peoples R China.
通讯机构：
[Zhang, XW; Wang, BB] U;Univ South China, Sch Environm & Safety Engn, Hengyang, Hunan, Peoples R China.
关键词：
Demulsification-coagulation-adsorbtion;Emulsifying wastewater;Fluorescent penetrant
摘要：
Fluorescent penetrant is used for the cleaning process of precision machine parts in non-destruc-tive testing (NDT). Wastewater will be produced in that course with high chemical oxygen demand (COD) (1000–15,000 mg/L), high mineral oil (300–3000 mg/L) and high chroma (600–2000). This liquid waste has a serious influence on the environment due to its’ stronger biological toxicity and higher virulence. When the oil content exceeds 0.01 mg/L in water, the water will lack oxygen and lead aquatic plants and animals to die, thus create badly water pollution. How to treat this polluted water is a difficult task in sewage treatment. The demulsification-coagulation-adsorption process was adapted for conducting this emulsifying wastewater. This research has compared the demulsification effects between the nonionic surfactant demulsifier of AR and the electrolyte demulsifier of CaCl2 and MgCl2 as well as the coagulation performance between the polymeric aluminum chloride (PAC) and the polyaluminium chloride sulfate (PACS). Effects of the types of demulsifier and coagulant, dosage, pH, static duration, absorbing time and other process parameters have been investigated. Based on this, the process parameters have been optimized. The results shown that the best treatment condition was using AR as demulsifier, PACS as flocculant, and vermiculite as adsorbent, which resulted in higher quality and efficiency in removal of 97.87% COD, 99.62% oil and 99.22% colority. This could meet the first grade standard of the national integrated wastewater discharge standard (GB8978-1996). Thus, the integration method of demulsification-coagulation-adsorbtion is a practicable way to solve this kind of sewage. © 2017 Desalination Publications. All rights reserved.
语种：
英文
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Extraction of uranium from tailings by sulfuric acid leaching with oxidants
作者：
Huang, Jing;Li, Mi* ;Zhang, Xiaowen;Huang, Chunmei;Wu, Xiaoyan
期刊：
IOP Conference Series: Earth and Environmental Science ,2017年69(1) ISSN：1755-1307
通讯作者：
Li, Mi
作者机构：
[Li, Mi; Huang, Jing; Zhang, Xiaowen; Huang, Chunmei; Wu, Xiaoyan] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Zhang, Xiaowen] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
通讯机构：
[Li, Mi] U;Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.;Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
会议名称：
3rd International Conference on Advances in Energy, Environment and Chemical Engineering (AEECE)
会议时间：
MAY 26-28, 2017
会议地点：
Chengdu, PEOPLES R CHINA
会议主办单位：
[Huang, Jing;Li, Mi;Zhang, Xiaowen;Huang, Chunmei;Wu, Xiaoyan] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.^[Li, Mi;Zhang, Xiaowen] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
会议论文集名称：
IOP Conference Series-Earth and Environmental Science
摘要：
Recovery of uranium have been performed by leaching uranium-containing tailings in sulfuric acid system with the assistance of HF, HClO4, H2O2 and MnO2. The effect of reagent dosage, sulfuric acid concentration, Liquid/solid ratio, reaction temperature and particle size on the leaching of uranium were investigated. The results show that addiction of HF, HClO4, H2O2 and MnO2 significantly increased the extraction of uranium under 1M sulphuric acid condition and under the optimum reaction conditions a dissolution fraction of 85% by HClO4, 90% by HF, 95% by H2O2 can be reached respectively. The variation of technological mineralogy properites of tailings during leaching process show that the assistants can break gangue effectively. These observations suggest that optimum oxidants could potentially influence the extraction of uranium from tailings even under dilute acid condition. ©Published under licence by IOP Publishing Ltd.
语种：
英文
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