8-羟基喹哪啶螯合树脂吸附钯(Ⅱ)的性能研究

用静态法研究了8-羟基喹哪啶螯合树脂在酸性溶液中吸附和解吸Pd(II)的性能，分析了吸附等温线和吸附动力学过程。结果表明，在0.6 mol/L HCl的介质中，树脂对Pd(II)的饱和吸附量为99.46 mg/g，吸附率为94.7%，解吸率达到95.6%；吸附过程符合Langmuir和Freundlich等温吸附模型，准二级动力学Lagergren方程更适合描述此吸附过程。     

螺旋藻粉生物质回收稀土元素Yb(Ⅲ):吸附等温线、动力学和热力学

研究以螺旋藻粉作为吸附剂从废水溶液中回收Yb(Ⅲ)的吸附特性和机理.利用SEM和XPS对吸附剂的表面结构以及元素价态进行分析,探究螺旋藻粉对Yb(Ⅲ)的吸附机理;通过吸附等温线、动力学和热力学模型分析螺旋藻粉对Yb(Ⅲ)的吸附特性.Langmuir模型表明,当温度为318 K时,螺旋藻粉对Yb(Ⅲ)的最大吸附量为72....     

普罗维登斯菌和希瓦氏菌对Pt(IV)的吸附特性

研究了普罗维登斯菌和希瓦氏菌两种微生物对Pt(IV)的吸附特性。pH和离子强度条件优化实验结果表明,pH=2.0时吸附效果较好,吸附量分别为58.62和72.20 mg/g;随着离子强度的增加,普罗维登斯菌对Pt(IV)的吸附量增加而希瓦氏菌却降低;Pt(IV)和Pd(II)共存时,两种微生物吸附剂均优先吸附Pd(II)。动力学和等温吸附实验结果表明,普罗维登斯菌吸附Pt(IV)的过程更符合拟二级动力学模型和Langmuir等温模型,说明化学吸附是该过程的限速步骤,且为单分子层吸附,其理论最大吸附量为136.10 mg/g。因此,以上研究结果表明,普罗维登斯菌和希瓦氏菌可以吸附回收溶液中的Pt(IV)离子。     

Removal of cadmium and zinc ions from aqueous solution by living Aspergillus niger

1 Introduction Heavy metals like copper, mercury, chromium, cadmium, lead, nickel and zinc cause serious threat to environment, animals and human for their extreme toxicity[1]. Many industries including metal plating, mining, battery, pigment, dyestuff a…     

Equilibrium and kinetic data of adsorption and separation for zirconium and hafnium onto MIBK extraction resin

The equilibrium and kinetics of methyl isobutyl ketone (MIBK) extraction resin for adsorption and separation of zirconium and hafnium were studied under the different conditions of acidity, initial total concentrations of zirconium and hafnium and temperature. The equilibrium data of both zirconium and hafnium are found to follow the Freundlich adsorption isotherm, and the Freundlich isotherm constants (K_F) are 3.53 and 0.64 mg/g, respectively. The equilibrium data of zirconium also fit the Langmuir adsorption isotherm, and the saturation adsorption capacity (Q_max) and the Langmuir isotherm constant (K_L) are 75.93 mg/g and ?0.012 7 L/g, respectively. The obtained kinetic data of both zirconium and hafnium are found to fit the HO pseudo-second-order kinetic model, and the rate constants of pseudo-second-order equation (k₂) are ?0.019 and 0.41 g/(mg·min), respectively. Column tests show that the MIBK extraction resin could be used as efficient adsorbent material for separating hafnium from zirconium.     

S300树脂对汽车失效催化剂浸出液中Pd(Ⅱ)的吸附行为

基于实验室合成的S300树脂对汽车失效催化剂浸出液中Pd2+吸附过程进行研究,考察温度、溶液体系中HCl浓度、吸附时间等因素对Pd2+在S300树脂上吸附行为的影响,并对Pd2+在S300树脂中的动力学特性、交换等温线、复杂体系中的选择性以及解吸过程进行研究,根据表征结果分析在盐酸体系下S300树脂的吸附机理.结果表明...     

壳聚糖固定化枯草芽孢杆菌水溶液中铜离子的吸附(英文)

研究了壳聚糖固定化枯草芽孢杆菌吸附铜离子的性能,分析了pH、吸附剂投加量、温度、铜离子初始浓度和时间对铜离子吸附的影响。结果表明,pH对铜离子的吸附有较大的影响。此外,固定化枯草芽孢杆菌吸附剂比空白吸附剂具有更强的吸附性能。整个吸附过程符合朗缪尔吸附模型(R2=0.994),最大吸附量为100.70mg/L。动力学模型拟合结果表明,实验符合准二级动力学模型,线性相关指数大于0.999。吸附剂能在0.1mol/LNaOH溶液中被成功解吸。     

Thermodynamics and kinetics of fluoride removal from simulated zinc sulfate solution by La(III)-modified zeolite

To understand the mechanism of fluoride removal from the simulated zinc sulfate solution by the La(III)-modified zeolite, the adsorbent was characterized by XRD, SEM and EDS. The effects of absorbent dose and contact time, the adsorption isotherms and the sorption kinetics were investigated. The experimental results were compatible with the Langmuir isotherm model. The theoretical maximum adsorption capacities are 20.83 and 23.04 mg/g at 303 and 313 K, respectively. And the physisorption is revealed using the Temkin isotherm model and the D–R isotherm model. The sorption process is more suitable by the pseudo-second-order kinetic models. Thermodynamic parameters such as standard free energy change (ΔG^Θ<0 kJ/mol), standard enthalpy change (ΔH^Θ=8.28 kJ/mol) and standard entropy change (ΔS^Θ=0.030 kJ/(mol·K)) indicate the spontaneity of adsorption and endothermic physical sorption. Furthermore, the fluoride concentration in the industrial zinc sulfate solution decreases from 98.05 to 44.09 mg/L with the adsorbent dosage of 15 g/L.     

纳米Fe3O4负载啤酒酵母菌对铀的吸附性能与机理

以纳米Fe3O4磁性微粒负载啤酒酵母菌,制备一种新型铀吸附剂,考察其吸附铀的主要影响因素,即溶液pH值、铀初始浓度、吸附剂投加量及其粒度,分析吸附过程的反应动力学和等温吸附规律,并用扫描电镜和能谱仪分析吸附机理。结果表明:纳米Fe3O4负载啤酒酵母菌(NFSC)吸附铀的最佳条件是pH值为7.0,铀初始浓度为60 mg/L,NFSC加入量为50 mg,NFSC的最佳粒径为12 nm。NFSC对铀的吸附动力学较好地符合准二级动力学模型,相关系数为0.999 6;吸附等温线均能符合Langmuir和Freundlich等温线模型,说明该吸附体系是一个单层覆盖与多层吸附相结合的模式。扫描电镜和能谱图表明:NFSC吸附铀后表面形态发生变化,且吸附过程中共存物理吸附和化学吸附,属于混合吸附类型。     

Efficiency,mechanism and microbial community of Cd(II) removal by mixed bacteria enriched from heavy metals mine soil

Mixed bacteria were enriched from heavy metals mine soil for cadmium (Cd(II))-containing wastewater treatment. Batch adsorption experiment results showed that the optimal pH, temperature, initial Cd(II) concentration, and biomass dosage were 6.0, 30 °C, 20 mg/L, and 1 g/L, respectively. Living biomass exhibited better Cd(II) removal efficiency (91.97%) than autoclaved biomass (79.54%) under optimal conditions. The isotherms and kinetics of living biomass conformed to the Langmuir isotherm model and pseudo-first-order kinetic model, respectively. FTIR results implied that amine groups, hydroxyl groups and phosphoric acid play an important role in the Cd(II) adsorption process, while XRD results showed that crystalline Cd(OH)₂ and CdO were obtained. After Cd(II)-containing wastewater treatment exposure, the dominant bacteria genera included Comamonas (39.94%), unclassified_f__Enterobacteriaceae (34.96%), Ochrobactrum (14.07%), Alcaligenes (4.84%), Bordetella (2.07%), Serratia (1.04%), and Bacillus (1.01%). Function prediction showed that the abundance of metabolic genes changed significantly. This study proposes the potential application of mixed bacteria for Cd(II)-containing wastewater treatment.     

微生物固定化吸附剂吸附Pd(II)的研究

微生物法在吸附处理重金属污染和回收贵金属方面具有广阔的发展前景。利用载体A固定化大肠杆菌开发了一种高效微生物固定化吸附剂,研究其对Pd(II)的吸附特性,构建其对Pd(II)的动态吸附模型,并开展了循环再生实验。结果表明,吸附柱的穿透时间和耗竭时间与大肠杆菌的浓度、微生物固定化吸附剂的填充量成正相关,与溶液流速成负相关;载体A:粘结剂:大肠杆菌的质量比为4:1:3,固定化吸附剂添加量为15 g、溶液流速3 mL/min时,吸附柱对Pd(II)有较好的吸附效率,穿透时间和耗竭时间分别为60 min和360 min;使用2 mol/L的HCl对负载Pd(II)后吸附剂进行解吸处理,解吸率达到99.32%;吸附-解吸循环5次后,固定化吸附剂对Pd(II)的吸附量基本保持不变。     

Adsorption behavior of Pd(Ⅱ) from aqueous solutions by D201 resin

The adsorption and desorption behaviors of Pd(Ⅱ) on D201 resin were investigated. The effects of parameters including HCl concentrations, initial metal ion concentrations, contact time, and temperature on the adsorption of Pd(Ⅱ) were studied by batch method. The HCl concentration for studying the effects was set from 0.01 to 2 mol·L-1 and the optimal adsorption condition is in 0.01 mol·L-1 HCl solution. The adsorption isotherm of Pd(Ⅱ) on D201 resin was determined and the equilibrium data fitted the Langmui...     

Direct extraction of Mo(VI) from acidic leach solution of molybdenite ore by ion exchange resin: Batch and column adsorption studies

The adsorption behavior of ion exchange resin D301 in the extraction of hexavalent molybdenum from high acidic leach solution was investigated. SEM, EDS and Raman spectra analyses were applied to studying the adsorption capacity, reaction kinetics and possible adsorption mechanism in detail. Results showed that the adsorption capacity of D301 resin for molybdenum from high acidic leach solution was up to 463.63 mg/g. Results of the kinetic analysis indicated that the adsorption process was controlled by the particle diffusion with the activation energy 25.47 kJ/mol (0.9α1.2 mm) and 20.38 kJ/mol (0.6α0.9 mm). Furthermore, the molybdenum loaded on the resin could be eluted by using 2 mol/L ammonia hydroxide solution. Besides, dynamic continuous column experiments verified direct extraction of molybdenum from acidic leach solutions by ion exchange resin D301 and the upstream flow improved dynamic continuous absorption.     

壳聚糖/三乙醇胺-银离子印迹膜的吸附性能研究

研究了壳聚糖/三乙醇胺-银离子印迹膜(Ag(I)-IICTM)的吸附性能。结果表明,Ag(I)-IICTM对银离子的吸附符合Langumir等温方程,为单分子层可逆化学吸附,其最大吸附容量为505 mg/g;吸附过程符合拟二级动力学方程,属颗粒内扩散。吸附条件研究显示,最佳吸附温度和酸度分别为50℃和pH=6,该印迹膜对Ag(I)的选择性远大于常见的Cu~(2+)、Pb~(2+)和Zn~(2+)离子。     

大肠杆菌对钯(Ⅱ)的吸附机理研究

用FTIR、XPS、TEM等表征方法对溶液中大肠杆菌吸附钯(Ⅱ)的机理行了研究。结果表明,该吸附过程与大肠杆菌和钯(Ⅱ)间静电作用有关,在pH为2.0时吸附量最大,可达120.08 mg/g;对大肠杆菌进行化学修饰,FTIR结果表明细胞表面的氨基、羧基可能为吸附钯(Ⅱ)的主要基团,涉及到表面络合机制;TEM及XPS结果显示吸附6 h后菌体内有尺寸为5~15 nm的钯纳米颗粒生成,说明该吸附过程还存在还原反应。大肠杆菌对钯(Ⅱ)的吸附过程是静电作用、表面络合、氧化还原等机制共同作用的结果。     

焙烧型CuZnAl双金属氢氧化物对水中苯丙氨酸的脱除(英文)

用水热法合成了Cu-Zn-Al-CO3双金属氢氧化物n(Cu)/n(Zn)=5,[n(Cu)+n(Zn)]/n(Al)≈2,简写为LDH),加热煅烧后得到焙烧型Cu-Zn-Al-CO3-LDH(CLDH),再采用批处理实验用其对模拟废水中的苯丙氨酸进行吸附。结果表明,CLDH对于废水中的苯丙氨酸是一种有效的吸附剂,其吸附效率明显高于同等条件下的LDH,当水相pH为6.7时,其吸附效率最高,吸附容量达到37.25mg/g。该吸附过程符合Lagergren准一级动力学模型,同时其平衡吸附等温线能很好地符合Langmuir等温方程,通过对吸附热力学研究发现,△GΘ计算值为负,△HΘ计算值为正,这表明此类吸附本质上为吸热自发过程。吸附机理表明苯甲酸分子在层间是倾斜的,与羟基层形成了一个角度。     

Behavior of ammonium adsorption by clay mineral halloysite

Ammonium pollution becomes severe during mining of ionic rare earth-ores in southern China. As one of the main clay minerals in soils of ionic rare earth mines, halloysite plays an important role in ammonium adsorption. In this study, the saturated adsorption capacity, factors affecting adsorption and adsorption kinetics of halloysite for ammonium were investigated. The results indicated that the ammonium adsorption of halloysite was saturated with 1.66 mg/g at 303 K, pH of 5.6 and initial ammonium concentration of 600 mg/L (about half of the actual initial in-situ leaching concentration). When the initial concentration of –N, pH values and temperatures (288 K to 313 K) increased, the ammonium adsorption capacity of halloysite increased. The ammonium isothermal adsorption of halloysite matched the Langmuir and Freundlich isotherms. The adsorption process of ionic rare earth mining soils for ammonium was favorable. And the adsorption process followed closely the pseudo-second kinetic equation.     

电化学法研究芭蕉叶提取物在盐酸中对碳钢的缓蚀作用

目的研究芭蕉叶提取物(MBLE)在酸性环境中对碳钢腐蚀的抑制行为。方法通过热水浸提法获取MBLE,采用电化学方法研究在不同实验温度和不同浓度下MBLE在1 mol/L盐酸溶液中对碳钢的缓蚀行为,并用扫描电镜(SEM)研究金属表面腐蚀形貌。结果极化曲线研究表明,MBLE对碳钢在1mol/L盐酸中的腐蚀有明显抑制作用,属阴极抑制为主的混合型缓蚀剂;其缓蚀性能随质量浓度增大而增强,25℃时160 mg/L的MBLE缓蚀效率达到94.7%。电化学阻抗图谱研究表明,随着MBLE质量浓度的增大,碳钢表面腐蚀反应的电荷转移电阻逐渐增大,腐蚀反应抑制程度增强。变温试验研究表明,MBLE在实验温度范围内具有较好的稳定性。当MBLE质量浓度为160 mg/L时,温度从25℃增加到40℃,两种电化学方法所得缓蚀效率的变化幅度均在3%以内。MBLE缓蚀剂分子在碳钢表面的吸附服从Dhar-Flory-Huggins等温吸附式,并且属于物理和化学混合吸附。SEM研究表明,盐酸介质中MBLE可有效地抑制碳钢的腐蚀。结论对碳钢在盐酸介质中的腐蚀,MBLE是有效的绿色缓蚀剂。     

Remediation of Pb-contaminated port sediment by biosurfactant from Bacillus sp. G1

The remediation of Pb-contaminated port sediment by biosurfactant from a new isolated Bacillus sp. G1 was studied. The Pb removal efficiencies were investigated under multi-levels of water–solid ratio, pH and ionic strength. Result showed that exchangeable speciation of Pb could be removed by maximum removal capacity of 76.8 mg/g after leaching. The Langmuir isotherm reflected the adsorption process best to fit the experimental adsorption equilibrium data. Fourier transform infrared spectra (FTIR) indicated that C=O and —CH₃ may be the functional groups. Scanning electron microscopy (SEM) analysis showed that the surface of the port sediment became much smoother after adsorption interaction, which reflected that the complexation between Pb ions and biosurfactant was more stable. The results indicated that the biosurfactant of Bacillus sp. G1 could remove Pb effectively from the Pb-contaminated port sediment (PCPS) and suggested a novel method for PCPS remediation.     

氧化石墨烯-镍铝/层状双金属氢氧化物-碳纤维复合材料的制备及其电吸附去除水中2,6-二氯苯酚

在化学镀镍废水溶液中,通过一种有效回收镍的方法,制备了以硝酸根为层间阴离子的氧化石墨烯-镍铝/层状双金属氢氧化物-碳纤维(GO-NiAl/LDHs-CFs)复合材料。采用傅立叶红外光谱仪、场发射扫描电子显微镜和X-射线衍射仪对制备的GO-NiAl/LDHs-CFs的表面形貌及结构进行了表征。将其用于电吸附处理水中2,6-二氯苯酚,考察了2,6-二氯苯酚初始浓度、电位、温度及时间等因素对电吸附效果的影响。结果显示:在0.1mol/L Na2SO4溶液中,1.0mmol/L初始浓度,0.2V电位,25℃,4h吸附时间,2,6-二氯苯酚的饱和吸附量为392.46mg/g。动力学和热力学研究表明,电吸附过程符合伪二阶动力学模型和Langmuir吸附模型,是自发的放热过程。