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1.
由溶液聚合法制备了聚(丙烯酰胺-丙烯酸钠)复合膨润土吸附剂。聚丙烯酰胺-丙烯酸钠复合膨润土对Pb2+的吸附过程符合Langmuir等温吸附,平衡吸附量为112.74 mg/g。聚丙烯酰胺-丙烯酸钠复合膨润土固定床穿透曲线较好地符合BDST模型,k a=0.300 L/(mg·min),N0=18.644 mg/L,Z0=1.152 cm,对Pb2+的去除率可达到90%。由TPHDM模型得到k f=6.40×10-6m/s,k s=4.31×10-9m/s,D L=3.25×10-8m/s,聚丙烯酰胺-丙烯酸钠复合膨润土固定床吸附Pb2+的传质阻力以轴向扩散控制为主。  相似文献   

2.
以钙基膨润土为主要原料,部分中和的丙烯酸为聚合单体,采用水溶液聚合法,制备了膨润土与未中和丙烯酸单体的质量比例为8:2的聚丙烯酸-丙烯酸钠钙基复合膨润土,并对其进行表征. 结果表明,单体插层在膨润土层间发生聚合反应,但未破坏钙基膨润土的片层结构. 复合膨润土产品对铅离子和氟离子具有良好的吸附和再生性能,吸附量优于钙基膨润土和文献报道的其他改性膨润土;0.5 g复合膨润土处理50 mL浓度为80 mg/L的Pb2+溶液和16.104 mg/L的F-溶液时,平衡吸附量和去除率分别为6.70 mg/g, 83.69%和1.01 mg/g, 62.95%. 复合膨润土对Pb2+和F-的平衡吸附分别符合Langmuir和Freundlich等温吸附方程.  相似文献   

3.
以丙烯酰胺为聚合单体,钙基膨润土为主要原料,采用钠化改性及水溶液聚合连续工艺合成了系列复合膨润土,对其进行了表征,并考察了丙烯酰胺的溶出量和对Pb2+的吸附性能. 结果表明,丙烯酰胺在膨润土层间发生了插层聚合,复合膨润土为片层结构,稳定性较好. 复合膨润土对Pb2+的吸附量高于粉末膨润土和钙基复合膨润土,且吸附量随膨润土含量增加而增加,膨润土含量为90%的钠基复合膨润土对Pb2+的吸附量可达118.35 mg/g,吸附符合Lagergren二级动力学模型.  相似文献   

4.
高吸水性树脂Super-Ⅰ对Pb~(2+)的吸附性能   总被引:3,自引:0,他引:3  
考察了聚(丙烯酸—co—丙烯酰胺)/凹凸棒黏土高吸水性树脂吸附剂(标记为Super-Ⅰ)对重金属Pb2+的吸附行为及溶液pH(3.0~7.0)、吸附时间(0~720 m in)、Pb2+溶液初始浓度(0.002 5~0.03 mol/L)和吸附剂加入量(0.08~0.30 g)等因素对吸附性能的影响。在pH=6.0、吸附时间60 m in、Pb2+溶液初始浓度0.02 mol/L和吸附剂用量0.1 g条件下,该吸附剂对Pb2+的吸附量达到296.0 mg/g。高吸水性树脂吸附剂对Pb2+的吸附行为符合准二级动力学模型和Langmu ir等温线模型。与常用多孔吸附剂相比,该三维网络吸附剂对Pb2+的吸附量高出1~2个数量级。  相似文献   

5.
采用动态吸附法研究三聚磷酸二氢铝吸附Pb2+的动力学行为并进行吸附活化状态热力学参数分析。结果表明:当三聚磷酸二氢铝粒径小于150μm,搅拌转速大于200 r/min,Pb2+的初始质量浓度为500 mg/L时,三聚磷酸二氢铝对Pb2+的化学吸附反应符合二级反应动力学方程,吸附速率常数k与温度T之间的关系符合Arrhenius公式,吸附活化能Ea=29.34 kJ/mol,吸附频率因子A=62.25 L/(mg.min),ln(k/T)与1/T之间的关系符合Eyring公式,其活化焓ΔH=27.31 kJ/mol,活化熵ΔS=-217.55 J/(mol.K)。  相似文献   

6.
《应用化工》2022,(3):582-585
使用溶胶-凝胶法合成聚丙烯酰胺磷酸锆,研究其对Pb(2+)的吸附行为。结果表明,0.10 g聚丙烯酰胺磷酸锆,加入0.20 g/L Pb(2+)的吸附行为。结果表明,0.10 g聚丙烯酰胺磷酸锆,加入0.20 g/L Pb(2+)溶液20.00 mL,24 h时已基本吸附饱和,q_e=18.50 mg/g,η=84.49%。当Pb(2+)溶液20.00 mL,24 h时已基本吸附饱和,q_e=18.50 mg/g,η=84.49%。当Pb(2+)初始浓度增加到0.70 g/L时,吸附容量达到最大,在pH=3.72时吸附容量最大。混合金属溶液吸附实验表明,聚丙烯酰胺磷酸锆对Pb(2+)初始浓度增加到0.70 g/L时,吸附容量达到最大,在pH=3.72时吸附容量最大。混合金属溶液吸附实验表明,聚丙烯酰胺磷酸锆对Pb(2+)具有高的选择性,k_(dPb)/k_(dNi)=23.76,k_(dPb)/k_(dCu)=6.680。吸附速率符合准二阶动力学方程。吸附等温线符合Langmuir吸附模型和Freundlich吸附模型。  相似文献   

7.
通过Acidithiobacillus ferrooxidans(简称A.f菌)代谢制备次生高铁矿物,研究矿物用量、吸附时间和初始Pb2+浓度对吸附性能的影响,借助等温吸附技术探讨该矿物对Pb2+的吸附平衡特征。结果表明,在Pb2+初始浓度为15 mg/L、体积为50 m L、温度30℃、pH为3.0、吸附时间为60 min、矿物用量为10 g/L的条件下,次生矿物对Pb2+的静态吸附率达90.67%,符合Langmuir静态吸附模型,最大吸附量达2.02 mg/g,吸附平衡常数(KL)为9.27 L/mg。  相似文献   

8.
孙志勇 《精细化工》2021,38(1):169-175,191
在磁性膨润土(MBent)表面接枝聚乙烯亚胺(PEI)制备了聚乙烯亚胺改性磁性膨润土(PEI/KH560/MBent),采用FTIR、VSM、XRD、TGA、EA、SEM和EDS对其进行了表征,考察了其对水溶液中Pb2+和Cu2+的吸附性能.结果表明,聚乙烯亚胺已成功接枝于磁性膨润土表面,并有效提高了其对Pb2+和Cu2+的吸附量;溶液初始pH对吸附量影响较大,随着pH的增大,吸附量增加.在pH=5,溶液初始质量浓度为300 mg/L,PEI/KH560/MBent对Pb2+和Cu2+吸附量分别为96.21和61.08 mg/g;吸附过程符合准二级动力学模型,吸附行为符合Langmuir吸附等温模型.热力学研究表明,吸附为自发吸热过程.经过5次循环利用后,其吸附容量仍保持初始的60%以上,表明PEI/KH560/MBent具有一定的重复利用性.  相似文献   

9.
陈双莉  张彤  党媛 《应用化工》2019,(3):582-585
使用溶胶-凝胶法合成聚丙烯酰胺磷酸锆,研究其对Pb~(2+)的吸附行为。结果表明,0.10 g聚丙烯酰胺磷酸锆,加入0.20 g/L Pb~(2+)溶液20.00 mL,24 h时已基本吸附饱和,q_e=18.50 mg/g,η=84.49%。当Pb~(2+)初始浓度增加到0.70 g/L时,吸附容量达到最大,在pH=3.72时吸附容量最大。混合金属溶液吸附实验表明,聚丙烯酰胺磷酸锆对Pb~(2+)具有高的选择性,k_(dPb)/k_(dNi)=23.76,k_(dPb)/k_(dCu)=6.680。吸附速率符合准二阶动力学方程。吸附等温线符合Langmuir吸附模型和Freundlich吸附模型。  相似文献   

10.
膨润土对水中聚丙烯酰胺的吸附行为研究   总被引:1,自引:0,他引:1  
为了降低聚丙烯酰胺(PAM)对反渗透膜的影响,采用膨润土对水中的PAM进行吸附处理。试验研究了膨润土和非离子聚丙烯酰胺的质量比为10∶1的情况下,PAM在膨润土上的吸附行为,探讨了吸附时间、温度、pH值对吸附效果的影响。结果表明:在温度为30℃,pH9,吸附时间为1 h的条件下,0.1 g膨润土对100mg/L PAM的吸附量为59 mg/g,其吸附行为符合Langmuir吸附等温模型和HO准二级动力学方程式。吸附焓变ΔH为23.62 kJ/mol,该吸附过程是吸热的自发过程。  相似文献   

11.
叙述了Fe3 、Zn2 、Mn2 、Cu2 、Ca2 、Mg2 等离子共存体系中采用六次甲基四胺 -铜试剂沉淀除去Fe3 、Zn2 、Mn2 、Cu2 等干扰离子 ,用EDTA滴定钙镁的方法 ,该方法钙的回收率在 99.7%~ 10 0 .3 % ;镁的回收率在 10 0 .0 %~ 10 0 .4% ,标准偏差为 0 .0 2 2。  相似文献   

12.
研究了(Gd3+,Ce3+/Ce4+,Eu3+)对Tb3+掺杂硅酸盐玻璃发光性能的影响.结果表明:Tb3+掺杂硅酸盐玻璃可以发出弱蓝光(400~460 mm)和较强的绿光(480~600mm).Gd3+对Tb3+的发光起敏化作用,可提高TB3+掺杂硅酸盐玻璃的发光强度.在空气中熔制的玻璃中Ce3+和Ce4+同时存在,Ce3+对Tb3+发光起敏化作用;而Ce4+对Tb3+发光起淬灭作用.由于Ce4+比例比较高,CeO2加入导致TB3+发光强度降低,同时也缩短了Tb3+发光余辉.加入Eu2O3时,Eu3+自身发光分散了激发Tb3+发光的能量,使Tb3+的特征发射强度降低.  相似文献   

13.
The rheological behavior of blends of poly(methyl methacrylate) (PMMA) and poly(acrylonitrile-stat-styrene)-graft-polybutadiene (ABS) was investigated using a cone-and-plate rheometer. The rheological properties measured were shear stress (σ12), viscosity (η), and first normal stress difference (N1) as functions of shear rate (\documentclass{article}\pagestyle{empty}\begin{document}$ \dot \gamma$ \end{document}) in steady shearing flow, and storage modulus (G′) and loss modulus (G″) as functions of frequency (ω) in oscillatory shearing flow. It has been found that the rheological behavior of blends of ABS and PMMA was very similar to that of blends of poly(styrene-stat-acrylonitrile) (SAN) and PMMA, in that N1 in logarithmic plots of N1 versus σ12, and G′ in logarithmic plots of G′ versus G″, vary regularly with blend composition. This has led us to conclude that the rubber particles that are grafted on an SAN resinous matrix in ABS resin plays only a minor role in influencing the compatibility of ABS/PMMA blends, and that the SAN chains attached to the surface of rubber particles, and the SAN matrix phase, play a major role in compatibilizing ABS resin with PMMA.  相似文献   

14.
Some biological aspects of the new complex imidazolium bisimidazole tetrachloro iridate(III)-IRIM- the iridium(III) analogue of ICR, were considered. More in detail the conformational effects produced by IRIM on DNA and the cytotoxic properties of IRIM on some selected human cell lines were measured. Dialysis experiments and DNA thermal denaturation studies are suggestive of poor binding of IRIM to DNA; formation of interstrand crosslinks is not observed. In any case CD measurements suggest that addition of increasing amounts of IRIM to calf thymus DNA results into significant spectral changes, that are diagnostic of a direct interaction with DNA. A number of experiments carried out on the A2780 human ovarian carcinoma, B16 murine melanoma, MCF7 and TS mammary adenocarcinoma tumor cell lines strongly point out that IRIM does not exhibit significant growth inhibition effects within the concentration range 10(-4)-10(-6) M. It is suggested that the lower biological effects of IRIM compared to ICR are a consequence of the larger kinetic inertness of the iridium(III) center with respect to ruthenium(III).  相似文献   

15.
Calcium phosphate (CaP) coatings can be applied to improve the biological performance of polymeric medical implants. For clinical applications, a strong adhesion of the coating to the polymeric substrate is important. Therefore, the adhesion of rf magnetron-sputter-deposited CaP coatings on five polymers was studied: polyethylene (PE), polystyrene (PS), poly(tetrafluoroethylene) (PTFE), poly-L-lactic acid (PLLA) and poly(dimethylsiloxane) (PDMS). To influence the adhesion, the interface was varied in six different ways, e. g. by a plasma or ion-beam pretreatment, or by using a Ti interlayer. The adhesion was determined by using scratch, tensile and 180° bend tests. Especially the polymers PE and PS needed a bombardment by energetic particles prior to or during coating deposition, to enable the formation of chemical bonds between the coating and the polymer, which gave adhesion. On PLLA and PDMS, being oxygen containing polymers, it was easier to establish a strong interface. An overtreatment of the polymeric substrates gave worse adhesion, probably due to the formation of weak low molecular weight (LMW) layers on the polymer. On PTFE, the use of a Ti interlayer was necessary to prevent the PTFE from UV degradation during coating deposition, as this caused cohesive failure within the PTFE. The results showed that each polymer requires a different approach for obtaining optimal adhesion. The observed adhesion could often be explained in the terms of processes occurred during the pretreatment of the polymers or the deposition of the coating.  相似文献   

16.
Poly[5,5??-methylene-bis(2-hydroxybenzaldehyde)1,2-phenylenediimine] resin was prepared and characterized by employing elemental, thermal analysis, FTIR, and UV?Cvisible spectroscopy. The metal uptake behavior of synthesized polymer towards Cu(II), Co(II), Ni(II), Fe(III) and Cd(II) ions was investigated and optimized with respect to pH, shaking speed, and equilibration time. The sorption data of all these metal ions followed Langmuir, Freundlich, and Dubinin?CRadushkevich isotherms. The Freundlich parameters were computed 1/n?=?0.31?±?0.02, 0.3091?±?0.02, 0.3201?±?0.05, 0.368?±?0.04, and 0.23?±?0.01, A?=?3.4?±?0.03, 4.31?±?0.02, 4.683?±?0.01, 5.43?±?0.03, and 2.8?±?0.05?mmol?g?1 for Cu(II), Co(II), Ni(II), Fe(III), and Cd(II) ions, respectively. The variation of sorption with temperature gives thermodynamic quantity (??H) in the range of 36.72?C53.21?kJ/mol. Using kinetic equations (Morris?CWeber and Lagergren equations), values of intraparticle transport and the first-order rate constant was computed for all the five metals ions. The sorption procedure is utilized to preconcentrate these ions prior to their determination by atomic absorption spectrometer. It was found that the adsorption capacity values for metal-ion intake followed the following order: Cd(II)?>?Co(II)?>?Fe(III)?>?Ni(II)?>?Cu(II).  相似文献   

17.
周志  林中祥  蔡凌云 《精细化工》2015,32(3):353-356
报道了以(+)-脱氢枞胺为起始原料,通过两条路线合成生物活性的二萜化合物(+)-弥罗松酚。路线(1):(+)-脱氢枞胺在羟氨-O-磺酸和氢氧化钠作用下还原脱氨生成脱氢松香烷,再经Friedele-Crafts乙酰化、BaeyerVilliger氧化、水解生成(+)-弥罗松酚,总产率29.5%。路线(2):(+)-脱氢枞胺还原脱氨,然后与过氧化邻苯二甲酰反应得到(+)-弥罗松酚,总产率31.9%。  相似文献   

18.
分析了Cd(S_xS_(el-x))颜料中CdSe所占比例不同时的呈色状况,研究了Cd(S_xS_(el-x))及ZrSiO_4-Cd(S_xS_(el-x))颜料的制备方法。  相似文献   

19.
20.
Stability constants of Copper(II), Nickel(II), Cobalt(II), Zinc(II), Uranyl(II) and Thorium(IV) adipates have been determined by paper electrophoresis. Adipic acid (0.005 mol dm?3) was added to the background electrolyte: 0.1 mol dm?3 HClO4. The proportions of (CH2)4COOH COO? and (CH2)4C2O=2 were varied by changing the pH of the electrolyte. These anions yielded the complexes Zn(CH2)4COOH COO+, Co(CH2)4COOH COO+, Ni(CH2)4COOH COO+, Th(CH2)4COOH COO3+, Th[(CH2)4COOH COO]4, Cu(CH2)4 C2O4 and UO2[(CH2)4(C2O4)]2?2, whose stability constants are found to be 102.8, 102.8, 103.2, 105.2, 1015.3, 102.7 and 1011.8 respectively (μ = 0.1, temp. 40°C).  相似文献   

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