哌嗪修饰XDA-200大孔树脂对诺氟沙星的吸附研究

通过对XDA-200大孔聚苯乙烯树脂进行哌嗪修饰制备了一种亲水性的NDA-201树脂,采用静态吸附的方法系统地研究了NDA-201对水溶液中诺氟沙星的静态吸附和脱附特征。结果表明,NDA-201树脂对诺氟沙星具有良好的吸附性能,在研究的浓度范围内, Langmuir和Freundlich等温吸附方程均能很好地拟合吸附平衡数据,吸附为放热的物理过程,吸附动力学符合Lagergren准二级速率方程,吸附速率受颗粒内扩散和液膜扩散双重作用。     

Comparison of the adsorption behavior of flavonoids on three macroporous adsorption resins modified with hydrogen‐bond groups

Three macroporous crosslinked poly(styrene‐co‐divinyl benzene) resins functionalized with p‐phenylene diamine (PPDA), p‐aminophenol, and p‐aminobenzoic acid (PANB) groups were prepared, and their adsorption characteristics for the flavonoid constituents from the leaves of Olea europaea L were studied. The materials were characterized by Fourier transform infrared spectroscopy. The specific surface area and the pore size distribution of the adsorbents were calculated by the Brunauer–Emmett–Teller and Barrett‐Joyner‐Halenda methods. The results show that the materials had a faster adsorption rate and high adsorption capacities for flavonoids, and PPDA had the highest adsorption capacity in comparison with the others. The isotherms could be fitted by the Freundlich model, and the adsorption was an exothermic process. The adsorption kinetics could be characterized by the pseudo‐second‐order rate equation, and the initial stage was controlled by the intraparticle diffusion model. This study contributes to the remediation of adsorption for organic materials and active components of natural products and to the effects of different functional groups on adsorption mechanisms. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40188.     

Modified activated carbons with amino groups and their copper adsorption properties in aqueous solution

Activated carbons were prepared by two chemical methods and the adsorption of Cu (II) on activated carbons from aqueous solution containing amino groups was studied. The first method involved the chlorination of activated carbon following by substitution of chloride groups with amino groups, and the second involved the nitrilation of activated carbon with reduction of nitro groups to amino groups. Resultant activated carbons were characterized in terms of porous structure, elemental analysis, FTIR spectroscopy, XPS, Boehm titration, and pHzpc. Kinetic and equilibrium tests were performed for copper adsorption in the batch mode. Also, adsorption mechanism and effect of pH on the adsorption of Cu (II) ions were discussed. Adsorption study shows enhanced adsorption for copper on the modified activated carbons, mainly by the presence of amino groups, and the Freundlich model is applicable for the activated carbons. It is suggested that binding of nitrogen atoms with Cu (II) ions is stronger than that with H+ions due to relatively higher divalent charge or stronger electrostatic force.     

Preparation of macroporous β-cyclodextrin matrix and its adsorption behaviors for rutin

以环氧氯丙烷(ECH)为交联剂,碳酸钙为扩孔剂,通过反向悬浮交联技术制备了一系列具有一定粒径分布、可用于色谱法分离的大孔β-环糊精/环氧氯丙烷复合介质。电子显微镜照片显示,介质具有良好的球形度,大孔基质的孔度和含水率均高于未扩孔的基质。此外,还研究了该基质对芦丁的静态及动态吸附性能,结果表明,大孔介质的静态吸附量和吸附速率均大于未扩孔的介质。     

Preparation of resins having various phosphonium groups and their adsorption and elution behavior for anionic surfactants

Resins containing phosphonium groups were prepared by reaction of chlorohydroxylated glycidylmethacrylate–divinylbenzene macroreticular resins with three trialkylphosphines. Triethylphosphine, tributylphosphine, and trioctylphosphine were used as trialkylphosphines. Adsorption and elution behavior of sodium benzenesulfonate (SBS) and sodium dodecylbenzenesulfonate (SDBS) on the resins were studied. Adsorption of SBS and SDBS increased with increasing the alkyl chain length of phosphonium groups in the resins. The adsorption of SBS decreased with increasing ionic strength of the solution, while the adsorption of SDBS increased with increasing ionic strength of the solution. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 371–378, 1999     

Characterization and adsorption behaviors of a novel synthesized mesoporous silica coated carbon composite

A novel mesoporous silica coated carbon composite(denoted SEG) with hierarchical pore structure has been successfully prepared in an aqueous solution that contains triblock copolymer template, aluminum chloride, siliceous source and expanded graphite. Textural property and morphology of the SEG composite were characterized by the combination of X-ray diffraction, N_2 adsorption–desorption, scanning electron microscopy,transmission electron microscopy and Fourier transform infrared measurements. Results show that mesoporous silica is steadily and uniformly grown on the surface of the graphite slices and the thickness of the silica layer can be finely tuned according to the silica/C molar ratio in the initial reaction solution. This newly synthesized SEG composite shows greatly increased adsorption capacity to methylene blue than the pristine expanded graphite in the batch tests. Both Langmuir and Frendlich models were further used to evaluate the adsorption isotherms of methylene blue over expanded graphite and SEG samples with different silica contents. Finally, pseudosecond-order model was used to describe the kinetics of methylene blue over expanded graphite and the silica-carbon composites.     

A novel reactive liquid rubber with maleimide end groups for the toughening of unsaturated polyester resins

An amino-terminated butadiene–acrylonitrile copolymer was chemically modified into a maleim-ido-terminated rubber and was used as a toughening agent for an unsaturated polyester resin. The reactive rubber was characterized by Fourier transform infrared spectroscopy. The mechanical and fracture properties of the blends containing the unmodified and the modified rubbers were investigated. Furthermore, a morphological analysis was carried out by scanning and transmission electron microscopy. A substantial enhancement of toughness was found when the modified rubber was used in place of the plain copolymer. © 1996 John Wiley & Sons, Inc.     

活性炭吸附法及浓硫酸氧化法脱除黄磷中的砷

分别采用活性炭和浓硫酸处理黄磷,研究其脱砷效果,并采用库仑滴定仪对脱砷效果进行检测,结果表明,活性炭脱砷可以采用累积处理的方法,经过三次处理后,黄磷中的砷质量分数由433×10-6降低到143×10-6,总脱砷率达到65.1%;浓硫酸氧化法的脱砷率可以达到60%。     

Preparation of macroreticular chelating resins containing dihydroxyphosphino and/or phosphono groups and their adsorption ability for uranium

The macroreticular chelating resins (RSP, RSPO, RCSP, and RCSPO) containing dihydroxy-phosphino and/or phosphono groups were prepared and their adsorption capacity for UO₂²⁺ and the recovery of uranium from sea water were investigated. RSP and RCSP were prepared by phosphorylation of macroreticular styrene–divinylbenzene copolymer beads and the chloromethylated copolymer beads, respectively. RSPO and RCSPO were prepared by oxidation of RSP and RCSP, respectively. The order of recovery of uranium from sea water with these four resins is as follows: RCSPO ? RCSP > RSPO > RSP. The adsorption of uranium in sea water was not only affected by the chemical structure, but also by physical structure of the resins. Uranium absorbed on the resins was eluted with 0.25 ～ 1 mol·dm^?3 Na₂CO₃ or NaHCO₃ solution by batch and column methods. The average recovery ratios of uranium from sea water with Na-form and H-form RCSP on 10 recycles were 84.9% and 90.5%, respectively, when 20 dm³ of sea water was passed through the column (resin 4 cm³, 10 mm ? × 50 mm) at the space velocity of 60 h^?1. RCSP has a high physical stability and resistance against acid and alkali solution.     

Thermal degradation behaviors and flame retardancy of epoxy resins with novel silicon‐containing flame retardant

A novel macromolecular silicon‐containing intumescent flame retardants (Si‐IFR) was synthesized, and its structure was a caged bicyclic macromolecule containing phosphorus‐silicon characterized by IR. Epoxy resins (EP) were modified with Si‐IFR to get the flame retardant EP, whose flammability and burning behavior were characterized by UL 94 and limiting oxygen index (LOI). Twenty percentage of weight of Si‐IFR was doped into EP to get 27.5% of LOI and UL 94 V‐0. The degradation behavior of the flame retardant EP was studied by thermogravimetry, differential thermogravimetry, scanning electron microscopy, and X‐ray photoelectron spectroscopy analysis. The experimental results exhibited that when EP/Si‐IFR was heated, the phosphorus‐containing groups firstly decompose to hydrate the char source‐containing groups to form a continuous and protective carbonaceous char, which changed into heat‐resistant swollen char by gaseous products from the nitrogen‐containing groups. Meanwhile, SiO₂ reacts with phosphate to yield silicophosphate, which stabilizes the swollen char. The barrier properties and thermal stability of the swollen char are most effective in resisting the transport of heat and mass to improve the flame retardancy and thermal stability of EP. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Kinetic behavior of photo‐polymerization of UV‐curable resins with carboxylic acid and amino groups

Photo‐polymerization behaviors of bisphenol‐A epoxy diacrylate (EPA) and six kinds of EPA‐derived resins containing different amounts of carboxylic acid, urethane, amide, and imide groups were studied by a photo differential scanning calorimetry. The dark polymerization was performed and pseudo‐steady state assumption of growing radicals was made to obtain the kinetic constants for propagation, bimolecular termination, monomolecular termination, and the concentration of growing radicals of different resins as a function of extent of reaction. Compared with EPA, it was found that the rate of polymerization and kinetic constants of the six resins were relatively small because the mobility of reacting species in resins was restricted by carboxylic acid, urethane, amide, and imide groups. Finally, three different photo‐initiators were used to initiate the polymerization, and their kinetic behaviors were compared. The effect of tertiary amine group of photo‐initiator on the rate of polymerization of resins having carboxylic acid group and the initiator efficiency were discussed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Impregnation synthesis of a novel macroporous silica-based crown ether polymeric material modified by 1-dodecanol and its adsorption for strontium and some coexistent metals

4,4′,(5′)-Di-(tert-butylcyclohexano)-18-crown-6(DtBuCH18C6) is a chelating agent having high selectivity mostly for Sr(II). To significantly reduce its leakage by molecular modification, a macroporous silica-based DtBuCH18C6 polymeric composite (DtDo/SiO₂–P) was synthesized. It was performed by impregnating and immobilizing DtBuCH18C6 and 1-dodecanol molecules into the pores of the SiO₂–P particles utilizing an advanced vacuum sucking technique. The adsorption of a few fission and non-fission products Sr(II), Ba(II), Cs(I), Ru(III), Mo(VI), Na(I), K(I), Pd(II), La(III), and Y(III) onto DtDo/SiO₂–P was investigated. It was done by examining the effects of contact time and the HNO₃ concentration in a range of 0.1–5.0 M at 298 K. At the optimum concentration of 2.0 M HNO₃, DtDo/SiO₂–P exhibited strong adsorption ability and high selectivity for Sr(II) great over all of the tested elements, which showed very weak or almost no adsorption except Ba(II). Meanwhile, It was found that the quantity of total organic carbon (TOC) leaked from DtDo/SiO₂–P in 2.0 M HNO₃, 187.5 ppm, was lower than 658.4 ppm that leaked from DtBuCH18C6/SiO₂–P, which was not modified. This was ascribed to the effective association of DtBuCH18C6 and 1-dodecanol through intermolecular interaction. The reduction of DtBuCH18C6 leakage by molecular modification with 1-dodecanol was achieved. It was of great benefit to application of DtDo/SiO₂–P in chromatographic partitioning of Sr(II), one of the main heat generators, from high level liquid waste (HLLW) in reprocessing of nuclear spent fuel in the MAREC (Minor Actinides Recovery from HLLW by Extraction Chromatography) process developed recently.     

The preparation,swelling characteristics,and albumin adsorption and release behaviors of a novel chitosan-based polyampholyte hydrogel

A novel chitosan (Ch)-based polyampholyte hydrogel was prepared from Ch dissolved in a 1:1 (v/v) mixture of 10% aqueous acetic acid and N-methyl-2-pyrrolidinone (NMP) by simple crosslinking using 1,2,3,4-butanetetracarboxylic dianhydride (BTCA). The detailed structure of the hydrogel was determined via FTIR and solid-state ¹³C NMR spectroscopic analyses. The swelling behavior of the hydrogels was strongly dependent on the BTCA feed ratio, and the hydrogels exhibited a pH-responsive swelling ratio that was influenced by the presence of both cationic NH₃⁺ and anionic COO^? groups within their molecular structures. The Ch hydrogels also exhibited bovine serum albumin (BSA) adsorption capacity, which was maximal at pH 4.5, consistent with the isoelectric point of BSA (4.7). In addition, the BSA adsorption capacity of the hydrogel decreased with the increasing ionic strength of the adsorption medium, indicating that the capacity of the hydrogel to adsorb BSA is facilitated by hydrophobic as well as electrostatic interactions between the hydrogels and the BSA molecules. In addition, a high desorption ratio (89%) of BSA was achieved in aqueous solutions at pH 2.0.     

Studies of selective adsorption resins. XXVI. Removal of calcium and magnesium ions in a salt solution with chelating resin containing aminomethylphosphonic acid groups

Removal of calcium and magnesium ions in a salt solution with the macroreticular chelating resin containing aminomethylphosphonic acid groups was investigated. The resin (RMT-P) exhibited high affinity for calcium and magnesium ions in a salt solution containing 200 g/dm³ of sodium chloride. In the column method, calcium and magnesium ions in a salt solution were preferentially absorbed on the RMT-P, when the salt solution containing 100 mg/dm³ of calcium or magnesium ion was passed through the RMT-P column at a space velocity of 15 h^?1. The calcium and magnesium ions adsorbed were eluted by allowing 1 mol/dm³ hydrochloric acid to pass through the column. The recycle of adsorption and elution was found to be satisfactory.     

Novel conventional and chelating anion exchange resins with amino ligands for sorption of silver

ABSTRACT

The polymeric resins containing diethylenetriamine, tetraethylenepentamine, 2-(diethylamino)ethanol, 1-methylimidazole, and 1,2-dimethylimidazole ligands have been synthesized from vinylbenzyl chloride-divinylbenzene copolymers and used in the removal of Ag(I) from chloride solution. The best Ag(I) sorption was reached in the case of 1-methylimidazole resin. Resins retain their capacity towards Ag(I) in five consecutive sorption/desorption cycles. The resins with imidazole ligands were highly selective for Ag(I) from synthetic chloride solution and they did not sorb chloride complexes of Cu(II). Additionally, the recovery of Ag(I) was tested from real chloride solution coming from leaching of the copper concentrate from Lubin Concentrator (KGHM Polska Mied? S.A.).     

Synthesis and characterization of wurtzite ZnS nanoplates through simple solvothermal method with a novel approach

A thio Schiff-base-assisted solvothermal process has been developed to synthesize zinc sulfide (ZnS) nanoplates via the reaction between a metal salt, Zn(NO₃)₂·6H₂O and thio Schiff-base of 2-(benzylidene amino) benzenethiol (C₁₃H₁₁NS) as a new precursor. XRD, TEM, SEAD, UV–vis spectroscopy, TG-DTA and FT-IR spectra were employed to characterize the obtained product. The results of this paper indicate that the shape and size of zinc sulfide nanoplates can be controlled systematically by setting certain reaction parameters, such as the reaction temperature and duration and type of solvent. Zinc sulfide nanoplates with different morphology and size have been successfully prepared.     

Copolymeric network crown ether resins with pendent functional group: Synthesis and adsorption for metal ions

Three network crown ether resins with a high content of pendent functional groups were prepared and characterized by IR, elemental analysis, and thermal analysis. The slight variance of the thermal stability of the resins was related to the kind and content of the pendent functional group. The adsorption capacity of the resins for Mg(II), Cu(II), Co(II), Pb(II), and Hg(II) was determined. Toward Hg(II), the adsorption capacity of the resins was high and the adsorption process was easy and spontaneously performed. The XPS study showed that the adsorption of the NCR–SN resin toward Cu(II), Pb(II), and Hg(II) was mainly the coordinate interactions between the ligand atom (S, N) of the pendent functional groups and the metal ions. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1457–1465, 2000     

Preparation of a macroporous silica–pyridine multidentate material and its adsorption behavior for some typical elements

A new macroporous silica‐based‐polymer (SiO₂‐P) soft ligand composite material, 2,6‐bis(5,6‐di(iso‐butyl)‐1,2,4‐triazine‐3‐yl)pyridine (BDIBTP/SiO₂‐P), was synthesized by impregnation and immobilization of BDIBTP and 1‐octanol molecules into the pores of the SiO₂‐P particles. The impact of some typical alkali metal and alkaline earths Cs(I), Na(I), K(I), Rb(I), Sr(II), and Ba(II) containing in highly active liquid waste (HLW) on the adsorption of Pd(II) onto BDIBTP/SiO₂‐P was studied. It was performed by examining the effects of contact time and the HNO₃ concentration in the range of 0.3–7.0 M. BDIBTP/SiO₂‐P showed strong adsorption ability and high selectivity for Pd(II) over all the tested metals. The chromatographic partitioning of Pd(II) from a simulated HLW solution was conducted by BDIBTP/SiO₂‐P packed column. Pd(II) was effectively eluted with 0.2 M thiourea–0.1 M HNO₃. The others showed no adverse impact on separation of Pd(II). The results are beneficial to partitioning of minor actinides and Pd(II) together from HLW by BDIBTP/SiO₂‐P in the MPS process developed. © 2012 American Institute of Chemical Engineers AIChE J, 2012     

Insight into the effect of surface carboxyl and amino groups on the adsorption of titanium dioxide for acid red G

In this study, TiO₂ functionalized with organic groups were prepared to study the effect of carboxyl and amino groups on the adsorption behavior of TiO₂ for the removal of acid red G (ARG) as an anionic dye from aqueous solution. TiO₂ was successfully modified with carboxyl and amino groups by using the hydrolysis method with oxalic acid (OAD, with two carboxyl groups), ethylenediamine (EDA, with two amino groups) and DL-alanine (DLA, with one carboxyl group and one amino group) at low temperature (65 °C) and labeled as OAD-TiO₂, EDA-TiO₂ and DLA-TiO₂, respectively. The ARG uptake by the functionalized TiO₂ samples was largely dependent on the functional groups. The interaction between ARG and the functional organic groups on the TiO₂ samples plays an important role in the adsorption process, which leads to the excellent adsorption performance (higher capacity and faster adsorption rate) of the functionalized TiO₂ samples than that of P25 (commercial TiO₂ without modification). Furthermore, there is no obvious loss of the adsorption capacity for the functionalized TiO₂ even after 5 adsorption-desorption cycles, which indicated the good reusability of the modified TiO₂ samples for anionic dye removal from aqueous solution.