改性膨润土吸附冶炼废水中Cu~(2+)和Ni~(2+)的动力学

研究了实验室制备的6种改性膨润土对冶炼废水中Cu2+和Ni 2+的吸附动力学。结果表明,改性膨润土对Cu2+、Ni 2+的吸附在40min内基本达到平衡,在30℃时,吸附符合准二级动力学模型,其反应速率与反应物浓度的二次方成正比。     

东北典型的棕壤对Cu~(2+)的吸附行为研究

研究了东北典型的棕壤对Cu2+的吸附行为,测定了不同pH值、不同的Cu2+初始浓度、不同铜盐对棕壤吸附Cu2+的影响。结果表明随着pH值增加,棕壤对Cu2+的吸附率也随着增加;在pH值3.00~6.09范围内,吸附率增加明显;随着Cu2+的初始浓度的不断提高,吸附率逐渐减小,为电性吸附;棕壤对不同铜盐吸附率大小的顺序是OAc-NO3-Cl-SO42-。     

硫脲树脂对Cu~(2+)吸附性能研究

考察了不同吸附时间、pH值和吸附温度下,聚对苯甲酰基硫脲树脂和聚酯基硫脲树脂对Cu2+的吸附性能影响;并对吸附动力学和热力学进行了研究。     

不同炭化材料和碳纤维对水中重金属Cu~(2+)的吸附研究

以花生壳、柑橘皮的不同炭化材料和碳纤维作为水中污染物的吸附剂,对重金属Cu2+进行了吸附研究。吸附试验结果表明:当改变水中p H时对吸附效果影响比较大,p H 5.5时吸附剂对水中Cu2+的吸附量最大;吸附时间在90 min后达到了吸附平衡状态;花生壳、柑橘皮吸附效果最好的加工炭化温度为250℃。     

高炉渣对Cu~(2 )的吸附性能研究

为了增加高炉渣的附加值,研制廉价高效吸附材料,本文采用静态吸附方法探讨了高炉渣对废水中Cu~(2 )的吸附性能。结果表明:高炉渣对废水中Cu~(2 )有很好的吸附去除效果,且容易达到平衡,平均去除率大于90%。其适宜投加量是:高炉渣/铜的质量比为100/1;高炉渣粒度、振荡转速对高炉渣吸附效果有一定的影响,但高炉渣能很好地适应废水离子初始浓度的变化。     

失效汽车尾气净化器催化剂浸出渣吸附Cu~(2+)、Cd~(2+)性能研究

以酸法处理失效汽车尾气净化器催化剂的浸出渣作为吸附剂,对废水模拟液中重金属Cu~(2+)、Cd~(2+)进行分离,考察了温度、pH、吸附剂用量和吸附时间对Cu~(2+)、Cd~(2+)吸附率的影响,得到了最优吸附条件:温度50℃、pH值5.5、吸附剂0.5g及吸附时间1h。在最优条件下,吸附剂对20mg/L的Cu~(2+)、Cd~(2+)吸附率分别为99.95%、99.22%,对1g/L的Cu~(2+)、Cd~(2+)饱和吸附量分别为99.61、42.17mg/g。浸出渣对Cu~(2+)、Cd~(2+)的吸附均符合二级动力学模型,吸附过程以化学吸附为主。     

蛋壳膜对溴金酸中Au~(3+)的吸附过程研究

考察了蛋壳膜吸附溴金酸中Au~(3+)时,吸附剂粒径、pH、吸附时间对吸附过程的影响,采用冷场发射扫描电镜(FESEM)、傅里叶变换红外光谱仪(FT-IR)和XRD对蛋壳膜吸附前后进行表征,研究了其吸附动力学和热力学方程。结果表明,蛋壳膜吸附Au~(3+)的最佳pH为6,蛋壳膜粒径在0.297~0.115mm内对吸附无明显影响。蛋壳膜对金的吸附是物理吸附和化学吸附共同作用的结果,且化学吸附起主要作用。25℃时最大吸附量为438.6mg/g。蛋壳膜对Au~(3+)的吸附符合Langmuir等温吸附方程,遵循准二级动力学方程。     

壳聚糖/磁性核桃壳生物炭的制备及其对高浓度Pb(Ⅱ)的吸附

以核桃壳粉作为生物质原料,依次采用H₂O₂和FeCl₃为改性剂,在限氧条件下制备磁性核桃壳生物炭,然后以壳聚糖为改性剂、聚乙二醇为交联剂,制备了壳聚糖/磁性核桃壳生物炭复合材料(CS/MWSB),采用SEM、FT-IR、N₂脱附、XRD、XPS、VSM技术对其形貌和理化性质进行表征,并通过静态试验考察了CS/MWSB对模拟废水中Pb(Ⅱ)的吸附性能。结果表明：CS/MWSB的表面有大量微孔结构,表面负载球状Fe₃O₄颗粒和壳聚糖,CS/MWSB的活性基团和芳香基团有所增加;壳聚糖负载量为30%的CS/MWSB对Pb(Ⅱ)的吸附能力最强;对于初始浓度为400 mg/L的Pb(Ⅱ)溶液,当吸附剂投加量为4 g/L时,在pH为5.0、温度为40℃吸附3 h时,CS/MWSB对Pb(Ⅱ)的吸附率达90.86%,吸附容量为89.86 mg/g; CS/MWSB对Pb(Ⅱ)的吸附符合准二级动力学方程,吸附过程以化学吸附为主。CS/MWSB可用于对于高浓度Pb(Ⅱ)废水...     

用废红茶从水溶液中吸附UO_2~(2+)的性能研究

研究了用福建南平武夷山废红茶粉末从水溶液中吸附UO2+2,考察溶液pH、离子强度等对铀的静态吸附的影响,采用固定床探讨初始铀质量浓度、溶液流速、废红茶用量对铀的动态吸附的影响。根据动力学模型、吸附等温模型拟合曲线以及吸附前后废红茶的FT-IR图谱推断吸附机制。     

改性蒙脱石对废水中Cr~(6+)的吸附性能研究

以蒙脱石为原料、硫酸为改性剂,采用正交试验研究了改性时间、硫酸浓度和固液比对蒙脱石吸附废水中Cr~(6+)吸附效果的影响。研究表明,改性后的蒙脱石层间距增大,吸附活性增强,纯度提高,具有较好的吸附性能。在改性时间180min、硫酸浓度2mol/L、固液比1∶4时,蒙脱石对Cr~(6+)的去除率达到77.99%,较原样提高24.26个百分点。当吸附时间120min、固液比1∶25、pH=5、Cr~(6+)初始浓度10mg/L时,改性蒙脱石对Cr~(6+)的去除率为87.95%,较原样提高了34.22个百分点。改性蒙脱石对Cr~(6+)的吸附更符合Freundlich等温吸附方程式,拟合系数为0.999 19,吸附方式更符合多分子层吸附,是可逆吸附。     

用HBL110从硫酸锌溶液中直接萃取分离铜镉钴的试验研究

研究了采用新型萃取剂HBL110从硫酸锌溶液中直接萃取分离Cu~(2+)、Cd~(2+)、Co~(2+),考察了萃取剂体积分数、有机相皂化度、萃取时间、相比对Cu~(2+)、Cd~(2+)、Co~(2+)、Zn~(2+)萃取率的影响。结果表明:在萃取剂体积分数45.6%、有机相皂化度100%、萃取时间10min、萃取相比2/1条件下,Cu~(2+)萃取率为96.41%,Cd~(2+)萃取率为85.54%,Co~(2+)萃取率为65.07%,Zn萃取率仅为6.64%,β(Cu/Zn)=331,β(Cd/Zn)=73.09,β(Co/Zn)=23.09,实现了硫酸锌与杂质Cu~(2+)、Cd~(2+)、Co~(2+)的有效分离。     

Fe-Al柱撑膨润土对水溶液中铜离子的吸附性能研究

制备了Fe-Al柱撑膨润土，研究了其对水溶液中铜离子的吸附去除性能，结果表明：Fe-Al柱撑膨润土对水溶液中的铜离子有很好的去除效果，当其用量为0．5g时，水溶液中铜离子的吸附去除率达到90．7％；Fe-Al柱撑膨润土对水溶液中的铜离子的吸附在60min达到平衡；溶液pH值对水溶液中铜离子的去除有一定的影响。在中性和弱碱性条件下的去除率大于酸性。平衡吸附量qe与平衡质量浓度pe之间的关系符合Freundlich和Langmuir等温吸附方程所描述的规律。     

Ni2+、Cu2+、Zn2+对氧化亚铁硫杆菌氧化 活性影响

为研究金属离子对氧化亚铁硫杆菌（Acidithiobacillus ferrooxidans,At.f）氧化活性的影响,通过测定经初步驯化的At.f菌在不同初始pH下的生长活性,开展不同浓度梯度的Ni2+、Cu2+、Zn2+及三种金属离子共存时对At.f菌的氧化活性影响的试验。结果表明,当初始pH为1.8时,At.f菌生长活性最好,且低浓度的Ni2+、Zn2+对At.f菌氧化活性影响较小,对两种金属离子的耐受浓度均在20 g/L以上;而该细菌对Cu2+比较敏感,当Cu2+浓度为2.5 g/L时,菌株的生长活性明显下降,特别是10 g/L时,对At.f菌的氧化能力有显著的抑制作用。三种金属离子同时存在时对At.f菌氧化活性的影响大于单一金属离子,当三种金属离子的浓度均为2.5 g/L时,在48小时内对At.f菌的氧化能力有显著的抑制作用,当三种金属离子的浓度均为5 g/L时,80小时时菌株对Fe2+的氧化率极低,说明At.f菌需要经过多种金属离子共存驯化培养后才能更好地运用于多金属复杂矿物的处理。     

剩余污泥裂解灰陶粒吸附酸性矿山废水中Zn2+、Cu2+、Pb2+性能及机理

以剩余污泥裂解灰为主要原材料,按照剩余污泥裂解灰︰膨润土︰淀粉为6︰3︰1的比例混合,经过造粒、熟化、干燥,最后于1 050 ℃氮气气氛下煅烧60 min制备多孔陶瓷颗粒。采用SEM-EDS、XRD表征陶粒吸附酸性矿山废水中Zn2+、Cu2+、Pb2+前后的微观形貌、元素变化及晶体结构。结果表明,所制备陶粒表面粗糙,具有大量孔隙结构。当陶粒投加量为3 g,初始pH=3.2,反应时间24 h时,制备的剩余污泥裂解灰陶粒对于Zn2+、Cu2+、Pb2+ 去除率分别达到99.2 0%、85.1 0%、96.27%。初始pH为中性时陶粒吸附效果优于酸性条件。陶粒对于Cu2+、Pb2+的吸附过程符合准二级动力学模型,以离子交换为主;对于Zn2+,准一级与准二级动力学模型均能较好拟合,物理吸附与化学吸附发挥同等重要作用。陶粒吸附过程均符合Freundlich等温模型,对于Cu2+的吸附主要发生在非均相活性位点,对于Zn2+和Pb2+的吸附既可以发生在均相单层也可以发生在非均相活性位点。利用剩余污泥裂解灰制备多孔陶瓷颗粒,不仅可以用于酸性矿山废水中处理重金属离子,还能解决污泥处置的问题,达到以废治污的目的。     

氨基膦酸型螯合树脂对水溶液中Ni2+,Fe2+,Fe3+吸附行为的研究

采用摇瓶法,考察了溶液中金属离子Ni2+,Fe2+,Fe3+浓度与氨基膦酸型螯合树脂D412相中金属离子吸附量的关系.结果表明,随着金属离子初始浓度的增大,平衡吸附量也在增大,树脂对Fe3+离子的吸附量明显大于对Ni2+和Fe2+离子的吸附量.以双曲线型(Lang-muir)吸附平衡模捌对试验数据进行拟和,线性回归参数R2>0.9.吸附与解吸过程的实验数据表明,氨基膦酸型螯合树脂用于镍矿浸出液分离提纯初步可行.     

Coordination geometries of selected transition metal ions (Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Hg2+) in metalloproteins

In order to determine preferred coordination geometries of six divalent cations (Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Hg2+), two sources of experimental data were exploited: Protein Data Bank and Cambridge Structural Database. Metal-binding sites of approximately 100 metalloproteins and 3000 smaller transition metal complexes were analyzed and classified. The correlation between the geometries of small-molecule crystal structures and the metal-binding sites in metalloproteins was investigated. The abundance of amino acid residues participating in coordination metal-protein bonds of metalloproteins was evaluated. From the performed analysis it follows that the octahedral arrangement is preferred by Co2+ and Ni2+, tetrahedral by Zn2+, square planar by Cu2+, and linear by Hg2+. Cadmium (II) cation tends to bind in both tetrahedral and octahedral arrangements and single coordination geometry cannot be unambiguously ascribed to it.     

含Ni~(2+),Fe~(3+),Mg~(2+)的硫酸盐溶液萃取分离Cu~(2+)

采用Lix984作萃取剂,煤油作稀释剂混合而成溶液萃取的有机相,从含Ni~(2+),Fe~(3+),Mg~(2+)离子的硫酸盐溶液中萃取分离Cu~(2+).实验结果表明,在一定范围内,铜萃取率随萃取剂浓度的升高、相比的增加、萃取时间的延长、初始水相pH值的增加、萃取温度的升高以及搅拌时间的延长而增加.本实验的优化条件为萃取剂体积分数达60%,相比为O∶A=2∶1,萃取时间为16 min,萃取初始水相pH值为2.5,萃取温度在25~45℃之间,搅拌速度为240 r/min.在最佳条件下,铜萃取率高达95.55%.Fe~(3+)萃取率为8.82%,Ni~(2+)的萃取率为5.47%,Mg~(2+)的萃取率为2.36%.从而达到Cu~(2+)与其它金属离子有效分离的效果.     

Complexes of carboxymethylcellulose in water. Part 2. Co2+ and Al3+ remediation studies of wastewaters with Co2+, Al3+, Cu2+, VO2+ and Mo6+

The properties of carboxymethylcellulose (CMC) complexes and Co²⁺ and Al³⁺ are reported in this work. The complexing power of CMC was greater to Al³⁺ than to Co²⁺, although it was not possible to determine some of the equilibrium constants. The infrared (IR) spectroscopy and thermal analysis helped in showing the existence of these complexes in the solid state. The films observed by scanning electron microscopy (SEM) provided a certainty that the chains of the biopolymer were not extensively broken by the use of strong mineral acid employed in some of the experimental steps of this study.Two water solutions — bidistilled and deionized water and an Iraí River, Curitiba, PR (Brazil) sample — were obtained by adding metal salts of Al³⁺, Co²⁺, Cu²⁺, Mo⁶⁺(initially in the form of molybdate) and VO²⁺ to which CMC was later added as a remediation agent. At different times, aliquots of those water samples were analyzed for their metal contents and showed ability to sequester different percentages of each of the metal ions, therefore, rendering the water samples within the Brazilian and Spanish standards for potable water (varying from < 0.3 to 5 mg/L depending on toxicity). The CMC complexes could be recovered by mechanical removal at the pH where these complexes are not very soluble. This process can be applied to municipal wasterwater treatment plants as CMC is a more cost-effective and non toxic alternative material than commercial employed alum. The metals can be recycled after the decomplexing process from the recovered solid complexes and with the additional benefit of using CMC that it will leave no trace of Al³⁺ ions in the water rising from the use of alum.     

The effects of Mg2+, Mn2+, Zn2+, and Al3+ on the nickel deposit during electrowinning from sulfate bath

The presence of impurities like Mg²⁺, Mn²⁺, Zn²⁺, and Al³⁺ during electrowinning of nickel shows several effects. The effects include current efficiency, deposit quality, purity, crystallographic orientation, surface morphology, and polarization behavior. Addition of the impurities did not change the current efficiency significantly but did change the quality and purity of the electrodeposited nickel. Based on the quality of the deposits obtained, the tolerance limits of these impurities in nickel bath were obtained. Although no deviation of nickel structure from fee was observed, the peak height values for different orientations changed with all of the impurities and the values varied with impurity concentration. The surface morphologies of electrodeposited nickel in the presence of impurities also showed changes. The potentiodynamic scan curves for nickel deposition showed deviations in the presence of all the impurities studied. Based on the results, an attempt was made to correlate the various effects.