新型硫脲螯合树脂对金(Ⅲ)吸附性能的研究

用静态法较系统地研究了新型硫脲树脂从酸性含金氯化溶液中吸附金及其解吸金的性能,结果表明,在实验条件下,新树脂在含有Au3+、Cu2+、Ni2+和Fe3+等离子的混合体系中,对Au3+有良好的吸附容量和选择性,并能定量地解吸树脂所吸附的Au3+。在适宜条件下,该树脂对金的吸附率和解吸率均达到98%以上。     

新型硫脲螯合树脂的合成及对钯(Ⅱ)吸附性能的研究

以聚苯乙烯树脂微球为原料,经硝化、还原、接枝等反应,合成了含有硫脲功能基的新型螯合树脂,研究了该树脂对Pd2 的吸附性能.结果表明,在实验条件下,新树脂在含有Pd2 、Cu2 、Zn2 和Fe3 等混合离子的体系中,对Pd2 有良好的吸附容量和选择性,并能定量地解吸树脂所吸附的Pd2 .     

聚苯乙烯基硫脲螯合树脂的制备及对Au(Ⅲ)吸附性能的研究

以氯甲基化聚苯乙烯树脂微球为原料,经胺化、接酯反应,合成了侧链上含有硫脲功能基的新型螯合树脂,研究了该树脂对Au(Ⅲ)的吸附性能。结果表明,树脂对Au(Ⅲ)吸附容量为1.84mmol.g-1,吸附过程符合G.E.Boyd液膜扩散方程,液膜扩散为吸附主控步骤;等温吸附可由Langmuir模型描述,为单分子层吸附。     

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Pd^2+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Pd^2+在S300树脂上吸附行为的影响,并对Pd^2+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:温度对Pd^2+吸附过程影响较小,溶液体系中的HCl浓度在0~1 mol/L范围内,S300树脂的平衡吸附量随HCl浓度升高而显著增加,平衡吸附时间约为30 min。S300树脂吸附过程符合准二级动力学模型与Langmuir等温模型,对汽车失效催化剂浸出液中Pd^2+的吸附分配系数DM=68.66,静态解吸过程中,解吸3 min后,Pd^2+解吸率达到98.79%。研究结果表明,溶液中Pd(Ⅱ)以[PdCl4]2?形式通过离子?偶极作用与S300树脂发生吸附反应。     

改性活性炭吸附金的性能

为了改善活性炭的吸附性能,以硫脲和甲醛为主要原料对活性炭进行了改性,并对改性活性炭的吸附性能进行了研究.静态吸附实验表明:改性活性炭在酸性环境中比在碱性溶液中对Au3 的吸附能力要强;无论是对金的吸附容量还是在含有重金属离子(Cu2 、Ni2 和Zn2 )的混合溶液中吸附金的选择性,改性活性炭都比一般活性炭强得多;改性活性炭几乎可将混合溶液中Au3 完全吸附,而对重金属离子Ni2 和Cu2 的吸附率不到1/3.改性活性炭对金的吸附符合Langmuir单分子层吸附规律.     

Au/α-Fe_2O_3 催化剂上金活性物种的分析(英文)

采用沉积沉淀法制备了CO低温氧化 Au/α-Fe2O3催化剂,利用 X 射线衍射(XRD)、X 射线光电子能谱(XPS)、BET 比表面测定、程序升温还原(H2-TPR)等表征技术,对比了制备过程 pH 值的微小变化、焙烧及光线照射对催化剂结构及催化性能的影响,探明了 Au/α-Fe2O3催化剂的活性物种。结果表明,110 ℃处理的 Au/α-Fe2O3催化剂表面同时存在 Au3+、Au0以及过渡态 Auδ+(0δ1),它们对 CO 氧化的活性顺序为 Au3+Auδ+Au0;pH 值为 8 条件下制备的催化剂 Au3+含量高、比表面积大,催化性能最好;高温焙烧使氧化态金还原的同时也使载体比表面积严重缩小,催化活性显著下降;紫外线照射可以引起 Au3+的逐渐还原以及 Au0 颗粒的生长,其催化失活作用弱于高温焙烧。     

Au/CuMn催化剂对于C3H8还原NO催化性能的研究

以沉积-沉淀法制备了系列Au/CuMn催化剂,并对催化剂进行了XRD和XPS等表征,研究了Au负载量和催化剂焙烧温度对Au/CuMn催化剂性能的影响。实验结果显示,60℃烘干、Au理论负载量为3%的催化剂性能最佳,在50℃的反应条件下,NO的转化率达到72.4%,但催化剂失活较快。XPS分析显示,催化剂表面的Au3+与吸附氧物种Oads.是反应的活性中心,反应过程中催化剂表面氧化态Au3+与Oads.物种部分被还原,可能是催化剂失活的重要原因。另外,反应后在催化剂表面生成的亚硝酸盐、硝酸盐和碳酸盐等物种,覆盖了活性中心,也是导致催化剂失活的原因之一。     

Analysis of the Active Au Species on Au/α-Fe2O3 Catalyst

采用沉积沉淀法制备了CO低温氧化 Au/α-Fe2O3催化剂,利用 X 射线衍射(XRD)、X 射线光电子能谱(XPS)、BET 比表面测定、程序升温还原(H2-TPR)等表征技术,对比了制备过程 pH 值的微小变化、焙烧及光线照射对催化剂结构及催化性能的影响,探明了 Au/α-Fe2O3催化剂的活性物种。结果表明,110 ℃处理的 Au/α-Fe2O3催化剂表面同时存在 Au3+、Au0以及过渡态 Auδ+(0<δ<1),它们对 CO 氧化的活性顺序为 Au3+>Auδ+>Au0;pH 值为 8 条件下制备的催化剂 Au3+含量高、比表面积大,催化性能最好;高温焙烧使氧化态金还原的同时也使载体比表面积严重缩小,催化活性显著下降;紫外线照射可以引起 Au3+的逐渐还原以及 Au0 颗粒的生长,其催化失活作用弱于高温焙烧。     

石油亚砜PSO3e萃取Au~(3+)的性能及机理研究

研究了石油亚砜PSO3e萃取Au3+时 ,萃取剂浓度、盐酸浓度对萃取率的影响。实验结果表明 ,在实验条件下 ,金的萃取率随着PSO3e的浓度和HCl的浓度增加而增加。还通过研究其它因素如Au3+、Cl- 、H+、PSO3e的浓度对分配系数的影响 ,确定萃合物的组成为HAuCl4·3PSO·mH2 O。此外 ,根据红外光谱研究萃取物的成键情况 ,得出PSO3e萃取Au3+的机理为酸性缔合机理 :H+3PSO(o) +mH2 O +AuCl4- 〔H·3PSO·mH2 O·AuCl4〕(o)     

D320树脂对Au(Ⅲ)的吸附性能研究

研究了D320树脂从酸性含金氯化溶液中吸附金的性能,考察了吸附时间、pH值、温度、氯离子浓度等因素对树脂吸附金的影响.结果表明,在pH=1时树脂的吸附效果最佳,静态饱和吸附容量可达到244.9mg/g(Au/干树脂),温度越高越有利于吸附,反应热焓△H=28.72kJ·mol-1.吸附平衡服从Freundish吸附等温式.用8%硫脲-1mol/L H2SO4混合液可以将树脂上的金完全解析.     

Adsorption behavior and mechanism of cadmium on strong-acid cation exchange resin

The adsorption behavior of Cd2+ on 001×7 strong-acid cation exchange resin was studied with the static adsorption method. The adsorption process was analyzed from thermodynamics and kinetics aspects. The influences of experimental parameters such as pH, temperature, initial concentration and adsorption rate were investigated. The experimental results show that in the studied concentration range, 001×7 resin has a good sorption ability for Cd2+, and the equilibrium adsorption data fit to Freundlich isotherms. The adsorption is an exothermic process which runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best adsorption condition is pH 4-5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the desorption efficiency is over 98%. The maximal static saturated adsorption capacity is 355 mg/g (wet resin) at 293 K. The adsorption mechanism of Cd2+ on 001×7 resin was discussed based on IR spectra.     

金属阳离子在锂辉石浮选中的活化行为及作用机理

在油酸浮选锂辉石体系中分别加入Ca^2+、Al^3+、Fe^3+离子,通过单矿物浮选试验、金属离子吸附量检测、金属离子水解组份浓度计算、矿物表面动电位测试、红外光谱检测以及量子化学模拟计算研究Ca^2+、Al^3+、Fe^3+离子对锂辉石浮选的活化行为和作用机理。结果表明:Ca^2+离子的最佳活化区间为pH大于12的强碱性条件,Al^3+离子的最佳活化pH为6.47,而Fe^3+离子的最佳活化pH为7.25;在这些pH区间内,锂辉石浮选回收率和金属离子吸附量均达到最大值。在锂辉石浮选过程中起活化作用的有效组份为它们分别对应的氢氧化物沉淀。Ca^2+、Al^3+、Fe^3+离子可使锂辉石表面动电位向正值方向显著偏移;Ca^2+离子在锂辉石表面双电层的外层发生静电吸附,Al^3+和Fe^3+离子在锂辉石表面双电层的内层发生特性吸附。钙原子与锂辉石矿物表面吸附后形成的Ca—O键的键强较小,以离子键为主;铁原子与矿物表面形成Fe—O化学键的键强较大,含有一定的共价键组份;而铝原子与矿物表面吸附后形成的Al—O键的键长、键强等参数介于钙、铁的参数之间。油酸在Ca^2+活化后的锂辉石表面发生了化学吸附和少量的物理吸附,而在Al^3+、Fe^3+活化后的锂辉石表面发生了较为强烈的化学吸附。     

Rare earth ion modified TiO2 sols for photocatalysis application under visible light excitation

TiO2 sols modified by rare earth (RE) ions (Ce^4 , Eu^3 , or Nd^3 ) were prepared by coprecipitation-peptizationmethod. The photocatalysis activity was studied by investigating the photodegradation effects of active brilliant red dye X-3B. It is found that TiO2 sols modified by Ce^4 , Eu^3 , or Nd^3 have the anatase crystalline structure, which are prepared at 70℃. All RE^n -TiO2 sol samples have uniform nanoparticles with similar morphology, which are homogenously distributed in aqueous colloidal systems. The particle sizes are 10.8, and 12 nm for Nd^3 -TiO2, Eu^3 -TiO2, and Ce^4 -TiO2, respectively. The character of ultrafine and positive charge sol particles contributes to the good adsorption of X-3B dye molecule on the surface of titania (about 30% X-3B adsorption amount). Experimental results exhibit that RE^n -TiO2 sol photocatalysts have the capability to photodegrade X-3B under visible light irradiation. Nd^3 -TiO2 and Eu^3 -TiO2 show higher photocatalytic activity than Ce^4 -TiO2, which is due to the difference of standard redox potential of RE^n /RE^(n-1) . RE^n -TiO2 sols demon-strate more excellent interfacial adsorption and photodegradation effects to X-3B than P25 TiO2 crystallites. Moreover, the degradation mechanism of X-3B is proposed as dye photosensitization and electron scavenging by rare earth ions.     

Adsorption properties of Ag（Ⅰ）, Au（Ⅲ）, Pd（Ⅱ） and Pt（Ⅳ） ions on commercial 717 anion-exchange resin

The adsorption properties of the four precious metal ions (Ag(I), Au(II), Pd(III) and Pt(IV)) on the commercial Cl^?-form 717 strongly basic anion-exchange resin were studied in detail. The effects of the contact time, solution acidity, and concentrations of Cl^? and Pb²⁺ ions on the adsorption properties were studied by the batch method. Then, the column method was conducted under the optimized adsorption conditions (pH=3.0). The effects of the sample loading flow rate and the length-to-diameter ratios of the columns were investigated. The precious metal ions adsorbed could not be eluted completely after the saturated adsorption because the precious metal ions were found to be reduced to their metallic states during the adsorption process. So, it is recommended that the commercial Cl^?-form 717 strongly basic anion-exchange resin should be decomposed directly to recovery the precious metals after the saturated adsorption.     

Adsorption behavior and mechanism of D113 resin for lanthanum

The sorption properties of macroporous weak acid resin (Dl13) for La3 ion were studied by chemical analysis and IR spectra. Experimental results indicate that the D113 resin has a good adsorption ability for La3 at pH = 6.0 in the HAc-NaAc medium. The statically saturated adsorption capacity is 273.3 mg/g. Separation coefficients of βLa3 / Ce3 , βLa3 / Gd3 , βLa3 / Er3 , and βLa3 /γ3 are 2.29, 3.64,4.27, and 0.627, respectively. The apparent activation energy of adsorption, Ea is 18.4 kJ/mol, the thermodynamics parameters △H, △S, and △G of Sorption are 4.53 kJ/mol, 61.8 J/(mol·K), -13.9 kJ/mol, respectively. The adsorption behavior of Dl13 for La3 obeys the Freundlich isotherm. La3 adsorbed on resin can be eluted by 2.0 mol/LHC1 quantitatively.     

Synthesis and fluorescence properties of terbium-calcium-PMDMBA

1　INTRODUCTIONInrecentyears,manyinvestigationsonfluores cencepropertiesofrareearthions containingpolymercomplexeshavebeenmadebecausethepolymerscanbeusedasluminescenceandlasermaterialswithgoodquality[15] .Okamotoetal[6 8] synthesizedpolymerscontainingcoordinationgroupsandstudiedtheirfluo rescenceproperties .However ,thesynthesisoffunc tionalgroupspolymerswith goodenergydonerandenergylevelmatchingcapabilitywasverycomplicat ed ,whichmadetheuseofpolymerluminescentmate rialsuneconomic[1] .Fur…     

MgCl_2改性柑橘皮对水溶液中重金属离子的吸附性能

以柑橘皮(OP)为原料,通过MgCl2进行改性制备新型柑橘皮生物吸附剂MgOP。考察溶液pH值、温度、固液比、吸附时间和金属离子浓度对MgOP从单组分溶液中吸附Cu2+、Cd2+、Pb2+、Zn2+和Ni2+的吸附性能的影响。结果表明,pH值和固液比对吸附率的影响较明显;温度对吸附率的影响较小;所有吸附过程可在20 min内达到吸附平衡,对5种金属离子的吸附动力学均符合准二级动力学方程;与原始柑橘皮相比,MgOP对5种金属离子的最大吸附量显著提高;MgOP可重复使用10次以上;共存金属离子对吸附率影响很小。     

茜素红-S螯合形成树脂吸附测定地质样品的金、铂和钯

以茜素红-S(1,2-二羟基蒽醌-3-磺酸钠)为螯合剂,与大孔强碱性阴离子树脂D296-R合成茜素红-S螯合形成树脂,能够在酸性介质中使螯合形成树脂中的-OH离解出H⁺,变成-O-,与大体积的贵金属碘络阴离子[MeI4]^2-相遇形成稳定的螯合物。在较宽的酸度范围内使Au、Pt、Pd与贱金属有效分离,并抑制NO3^-对贵金属吸附的影响。与高压密闭溶矿方式相结合,Au、Pt、Pd的回收率均大于92%,检出限:Au 0.047 ng/g、Pt 0.082 ng/g、Pd 0.051 ng/g。应用于铂族元素地球化学成分分析一级标准物质中Au、Pt、Pd的测定,结果与认定值的相对误差(RE)为-7.58% ~10.9%,相对标准偏差(RSD)均小于9.86%。