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1.
A study on the Pb(II) imprinting performed within mesoporous sulphated biopolymer/siloxane composites, prepared in media containing deep eutectic solvent (DES), is described. In general, the process of imprinting resulted in greatly increased surface areas relatively to the corresponding nonimprinted composites [up to fivefold (from 76 m2 g−1 to 360 m2 g−1) for fucoidan (Fuc) and up to twofold (from 208 m2 g−1 to 351 m2 g−1) for chondroitin sulfate (CS) composites], the diminishing of mean pore size (from 3.3–4.6 nm to 2.9–3.4), and higher biopolymer contents (from mass fractions of 0.42–0.52 to 0.46–0.68). The sorption features depended a great deal on the biopolymer/DES combination. The best CS composite, allowed for 12% capacity and 20% binding strength, as well as Pb(II)/Cd(II) selectivity enhancements. The largest of the capacities was obtained with the imprinted Fuc/DES-E composite, 86 mg g−1, a 10% increase. Concerning the selectivity [Pb(II) versus Cd(II)], there was a significant increase for the CS composites (from 1.0–1.1 (αqmax)/1.1–1.2 (αK) to 1.3–1.4 (αqmax)/1.3–1.6 (αK)]. In particular, the DES-E CIC presented high selectivity factors (αqmax 3.0/αK 3.2) in line with those of the microporous version (αqmax 2.0/αK 3.3) but showing a significant increase in terms of the αqmax selectivity. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48842.  相似文献   

2.
Lysozyme adsorption onto Cibacron Blue F3GA attached and Cu(II) incorporated poly(2-hydroxyethyl methacrylate–ethylene glycol dimethacrylate) [poly(HEMA-EGDMA)] microspheres was investigated. The microspheres were prepared by suspension polymerization. Various amounts of Cibacron Blue F3GA were attached covalently onto the microspheres by changing the initial concentration of dye in the reaction medium. The microspheres with a swelling ratio of 65%, and carrying different amounts of dye (between 1.4 and 22.5 µmol/g−1) were used in the lysozyme adsorption studies. Lysozyme adsorption on these microspheres from aqueous solutions containing different amounts of lysozyme at different pH values was investigated in batch reactors. The lysozyme adsorption capacity of the dye–metal chelated microspheres (238.2 mg g−1) was greater than that of the dye-attached microspheres (175.1 mg g−1). The maximum lyzozyme adsorption capacities (qm) and the dissociation constant (kd) values were found to be 204.9 mg g−1 and 0.0715 mg ml−1 with dye-attached and 270.7 mg g−1 and 0.0583 mg ml−1 with dye–metal chelated microspheres, respectively. More than 90% of the adsorbed lysozyme were desorbed in 60 min in the desorption medium containing 0.5 M KSCN at pH 8.0 or 25 mM EDTA at pH 4.9. © 1999 Society of Chemical Industry  相似文献   

3.
Molecularly imprinted polymers (MIPs) have been synthesized in the absence of a solvent using fumed silica nanoparticles to create a porous network. The method employed led to a chiral imprinting effect and allowed for an excellent control over the internal morphology of imprinted and non‐imprinted polymer (NIP) materials. The polymers possess high surface areas (>300 m2) and identical pore size (112 Å). The MIP exhibited an imprinting factor (IF) of 9 and a selectivity value (α) of 1.83 for (?)‐ephedrine. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44104.  相似文献   

4.
An affinity dye ligand, Cibacron Blue F3GA, was covalently attached onto magnetic poly(2‐hydroxyethyl methacrylate) (mPHEMA) beads for human serum albumin (HSA) adsorption from both aqueous solutions and human plasma. The mPHEMA beads, in the size range of 80 to 120 µm, were prepared by a modified suspension technique. Cibacron Blue F3GA molecules were incorporated on to the mPHEMA beads. The maximum amount of Cibacron Blue F3GA attachment was obtained as 68.3 µmol g?1. HSA adsorption onto unmodified and Cibacron Blue F3GA‐attached mPHEMA beads was investigated batchwise. The non‐specific adsorption of HSA was very low (1.8 mg g?1). Cibacron Blue F3GA attachment onto the beads significantly increased the HSA adsorption (94.5 mg g?1). The maximum HSA adsorption was observed at pH 5.0. Higher HSA adsorption was observed from human plasma (138.3 mg HSA g?1). Desorption of HSA from Cibacron Blue F3GA‐attached mPHEMA beads was obtained by using 0.1 M Tris/HCl buffer containing 0.5 M NaSCN. High desorption ratios (up to 98% of the adsorbed HSA) were observed. It was possible to re‐use Cibacron Blue F3GA‐attached mPHEMA beads without any significant decreases in their adsorption capacities. Copyright © 2004 Society of Chemical Industry  相似文献   

5.
pH and temperature dual‐sensitive protein imprinted microspheres with high absorption capacity have been successfully synthesized on the surface of SiO2 using chitosan grafted N‐isopropylacrylamide (CS‐g‐NIPAM) as the pH and temperature sensitive monomer, with acrylamide as comonomer, N,N′‐methylenebisacrylamide as the crosslinking agent and bovine serum albumin (BSA) as the template protein. The pH and temperature dual‐sensitivity was also investigated. The results showed that the adsorption capacity and imprinting factor improved slowly with increasing incubation pH from 4.6 to 7.0, and then decreased sharply in alkaline conditions due to the reduction of non‐specific binding from electrostatic and hydrogen bonding interactions. Fourier transform infrared spectroscopy, thermogravimetric analysis and transmission electron microscopy were used to characterize the polymers. The as‐prepared SiO2@BSA molecularly imprinted polymers were also found to have high adsorption capacity (119.88 mg g?1) within 2 h, an excellent imprinting factor (α = 2.25), specific selectivity and good reusability. © 2019 Society of Chemical Industry  相似文献   

6.
Molecular imprinting polymers (MIPs) for artemisinin were prepared by using 3‐aminopropyltriethoxysilane and calix[4]arene bonded on silica particle surface as the functional monomers, tetraethoxysilicane as cross‐linker, and artemisinin as template. The MIPs were characterized by Fourier Transform Infrared Spectroscope and SEM. Their adsorption capacities were evaluated by static adsorption experiments. The MIPs showed high adsorption capacity and good selectivity for artemisinin. The maximum adsorption capacity of MIPs for artemisinin was 40.0 mg/g. The imprinting factor and the selective factor of the artemisinin‐imprinting polymers was 2.0 and 1.5, respectively. The imprinted film coating onto the silica surface showed a fast kinetics for recognizing and binding templates. Especially, mass transfer reaches the equilibrium within 3.5 h and the adsorption capacity of MIPs for artemisinin reached 120.0 mg/g in supercritical CO2 fluid. © 2011 American Institute of Chemical Engineers AIChE J, 2011  相似文献   

7.
Novel silica (SiO2)-assisted urea-formaldehyde-based microspheres (SUFMs) have been successfully prepared by condensation polymerization with SiO2 nanoparticles as template. The support effect of SiO2 and the improved thermal stability of SUFM have been investigated. The SUFM is pyrolyzed at high temperature under Ar atmosphere to achieve its carbonized product (SUFCM), which retains its spherical morphology by alkali etching after carbonization. The SiO2 acts as a stabilizer that limits the flowing domain of the melt resin around the SiO2. When used as the electrode material for supercapacitors, the SUFCM exhibits excellent electrochemical performance with a high specific capacitance of 218 F g−1 at 1 A g−1 in 2 M H2SO4 aqueous electrolyte and a good rate capability of 138 F g−1 (63% capacitance retention) at 10 A g−1. More importantly, the SUFCM electrode demonstrates a robust long-term stability without capacitance fading after 10,000 cycles. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48388.  相似文献   

8.
Because of the good fluorescence of zinc phthalocyanine-phenolic resin (ZnPc-PFR) photosensitizer and large specific surface area of mesoporous silica nanoparticles (MSNs), a highly efficient nano-drug carrier system, denoted as ZnPc-PFR@MSN, was constructed for photothermal therapy (PTT) and pH-sensitive drug delivery. The facile hydrothermal reaction was used to synthesize ZnPc-PFR nanoparticles in one-step. After loading the as-synthesized ZnPc-PFR nanoparticles into MSNs, and a good high drug-loading rate (143.7 mg g−1) to the anticancer drug of Adriamycin (DOX) could be obtained. Thus, a novel nanosphere with the merits of good fluorescence, high drug-loading rate (143.7 mg g−1), better sustained-release properties, and photothermal properties (reached 43.23°C within 260 s) was prepared. The as-synthesized multifunctional composites make it a good candidate in fluorescence imaging, PTT, and drug delivery.  相似文献   

9.
In this study, the aim was to characterize the physicochemical properties and some bioactive compounds of expeller-pressed oils of five registered poppy seed varieties (TMO–1, Ofis–8, Ofis–96, Ofis–95, Ofis–3) grown in Turkey. The amounts of total carotenoids, chlorophylls, phenols, and antioxidant activities of oils ranged between 0.08–0.24 mg 100 g−1, 0.03–9.04 mg pheophytin a kg−1, 3.41–8.57 mg gallic acid equivalent 100 g−1, and 5.60–7.33 mM Trolox equivalent 100 g−1, respectively. The most abundant fatty acid in poppy seed oils was linoleic acid (69.85–74.02%), followed by oleic acid (13.98–16.99%), and palmitic acid (8.51–9.75%). In addition, poppy seed oils were rich in β–sitosterol (133.47–153.42 mg 100 g−1), campesterol (45.36–58.60 mg 100 g−1), and δ–5–avenasterol (28.21–39.40 mg 100 g−1). High amounts of γ–tocopherol and α–tocopherol were detected. This research is the first study, which identified and quantified the polyphenol, β–carotene, and lutein compounds of expeller–pressed poppy seed oils by HPLC. Tyrosol, apigenin, syringic acid, 3–hydroxytyrosol, luteolin, p–coumaric acid, quercetin, ferulic acid, sinapic acid, and veratric acid were detected in expeller-pressed poppy seed oils.  相似文献   

10.
Nano-hydroxyapatite (NHAp) with a novel rod shape was synthesized from an economical and easily accessible Labeo rohita fish scale bio-waste by facile and straightforward alkaline heat treatment method. The purity, functionality, morphology, and surface area of the green synthesized NHAp powder were well-characterized via X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET). The TEM and BET results indicate that the apatite is prepared as a rod-like particle and highly porous with high surface area (112.36 m2 g−1). The NHAp powder was used for the adsorptive removal of cationic dye-methylene blue (MB) from the aqueous samples. Batch experiments were performed to evaluate the mechanism of adsorption and kinetic models. The NHAp achieved an enhanced adsorption efficiency (666.67 mg g−1) for the adsorption process. The obtained results perfectly obeyed the pseudo-second-order model, and the Langmuir isotherm exhibited an excellent relationship with the experimental data. Furthermore, thermodynamic studies reveal that the adsorption process was exothermic and spontaneous. Thus, the results proved that Labeo rohita fish scale bio-waste derived NHAp can be inventively utilized as a cost-effective and eco-friendly adsorbent for wastewater treatment.  相似文献   

11.
A new dual-template surface imprinted polymer for Cu(II) and Pb(II) was synthesized in one pot. Magnetic graphene oxide was self-assembled with low cost and environmentally benign thiourea. Presence of sulfur and nitrogen donor atoms provide hooks for coordination and partial reduction of graphene oxide matrix. It was used as an solid-phase extraction adsorbent for extraction, preconcentration, and coupled with flame atomic absorption spectrometry to manifest performance comparable with inductively coupled plasma atomic emission spectrometry (ICPAES) both in terms of quantification limit as well as interference. The critical experimental parameters such as pH; 4.6, contact time of 15 min and initial concentration of 777 (Qe; 227 mg g−1) and 800 μg L−1 (Qe; 273 mg g−1) for Cu(II) and Pb(II), respectively, were optimized using RSM-CCD and artificial neural network. The adsorption process was kinetically faster (50% adsorption in 5 min), following fractal-like-pseudo-second-order (FLPSO) kinetics and Brouers–Sotolongo isotherm model owing to the heterogenous energy landscape. The imprinting factors were in the range of 4–7 in the presence of all coexisting ions. The proposed method was robust in the determination and removal of Cu(II) and Pb(II) from food, ground water, and industry effluents with low limit of detection (Cu(II); 1.03 μg L−1 & Pb(II); 1.79 μgL−1). Spiking and recovery tests were used to assess the method's accuracy. Cu(II)/Pb(II) loaded dual template IIP (DIIP) was utilized to remove anionic dyes with >95% efficiency. Thorough examination of the method and material selectivity (in binary, ternary, and multielement system), multi fold applications of determination, removal of Cu(II), Pb(II), and removal of anionic dyes makes DIIP a promising candidate for environmental remediation.  相似文献   

12.
This study analyzed the viability of using malacoculture residue (Mytella falcata) to produce layered double hydroxides (LDHs) and for its subsequent use as an adsorbent. The CaAl/LDH-RE material was produced with calcium oxide from the residue and the CaAl/LDH-AP was produced with a commercial reagent. Both were used to remove methyl orange (MO) and methylene blue (MB) dyes. The CaAl/LDH-RE presented a surface area of 28.54 m2 g−1, being 65.62% larger than the CaAl/LDH-AP material (17.23 m2 g−1). The adsorbents showed mesopores distributed on a surface formed by plates in the form of hexagonal sheets arranged in an overlapping manner. The dosage of 0.05 g L−1 obtained the removal of 95% and 97% for MO, while for MB it was 94% and 93% using the adsorbents LDH/CaAl-AP and LDH/CaAl-RE, respectively. The system reached equilibrium at 90 min for MO and 120 min for MB. The pseudo-second order model well represented the kinetic data reaching 11.36 mg g−1 (CaAl/LDH-RE) and 8.42 mg g−1 (CaAl/LDH-AP) for MO, and 4.47 mg g−1 (CaAl/LDH-RE) and 4.14 mg g−1 (CaAl/LDH-AP) for MB. The Freundlich model better represented the isothermal data, where the temperature exerted little influence. Adsorbents showed similar removal percentages in real and synthetic matrices. The LDH/CaAl-RE can be applied in up to 3 cycles, maintaining its adsorption capacity. These results corroborate the use of MFW to produce CaAl/LDH-RE, which can be used for the efficient removal of organic pollutants in an aqueous solution.  相似文献   

13.
Beneckea natriegens growing both in suspension and immobilised on diatomaceous earth (silica) support particles, in a 3 dm three phase air lift bioreactor (TPALB), was employed to demonstrate the relationship between substrate loading rate and immobilised biomass loading at steady state. Sterile conditions were maintained during the experiments, while the hydraulic conditions and the inlet flowrate remained constant. The experiment ran for 12 days, whilst the inlet substrate (n‐propanol) concentration was varied both upwards and downwards between 250 and 750 mg dm−3. The bulk liquid substrate concentration and the immobilised biomass loading were found to vary between 6–120 mg dm−3 and 71–159 mg(dry biomass) g−1 (silica), respectively. The experimental results demonstrated that there is a positive relationship between substrate loading and immobilised biomass loading. A mathematical model is proposed to calculate biofilm thickness and bulk liquid substrate concentration (for steady state) using the inlet flowrate and the inlet substrate concentration as input parameters. The model was able to predict both biofilm thickness and immobilised biomass loading for the lower substrate loading rates applied. © 1999 Society of Chemical Industry  相似文献   

14.
Active transition metal species (Co, Cu, Cr, Ni or Mn) supported on a chemically modified silica gel are used as heterogeneous catalysts in a range of liquid phase oxidation reactions: alkyl aromatic side chain oxidations, epoxidations of alkenes and Baeyer–Villiger oxidations of linear ketones to esters and cyclic ketones to lactones. The catalyst employs metal centres bound to the silica surface via a hydrophobic spacer chain and is thus chemically robust and has a relatively high loading for a supported reagent (c 0.4 mmol g−1). The Cr version of the catalyst promotes the oxidation of ethylbenzene to acetophenone in a solvent‐free system at a rate of 5.5% h−1 (>370 turnover h−1). It is also active for the oxidation of p‐chlorotoluene and p‐xylene to p‐chlorobenzoic acid and p‐toluic acid respectively. Cyclohexene is converted to its oxide at room temperature at a rate of c 28% h−1 (c 12 turnover h−1) using either the Ni or Cu versions of the catalyst. The room temperature Baeyer–Villiger oxidation of cyclohexanone is achieved at a rate of 44% h−1 (49 turnover h−1) using the Ni‐containing catalyst. The same material also promotes the Baeyer–Villiger oxidation of linear aliphatic ketones and aromatic side chains. All the above systems use either air or molecular oxygen as the oxidant rather than peroxides or peracids. © 1999 Society of Chemical Industry  相似文献   

15.
The pollution of heavy metal ions in water poses a serious threat to human being and ecosystems. Here, we report polyamidoxime (PAO) brush grafted graphene oxide (GO) as a highly efficient adsorbent for extraction of toxic metal cations from water. Surface-initiated atom transfer radical polymerization was used to grow polyacrylonitrile (PAN) brushes on GO, followed by conversion of the nitrile groups in PAN into amidoxime groups, which had high binding affinity toward heavy metal cations. The PAO brush grafted GO demonstrated significantly fast adsorption kinetics and large adsorption capacity. At optimal pH 5, the PAO brush grafted GO can achieve maximum adsorption capacities of 116.7 mg g−1 for Pb(II), 258.6 mg g−1 for Ag(I), 192.2 mg g−1 for Cu(II), and 167.9 mg g−1 for Fe(III), which were significantly larger than those of small molecule functionalized GO. Mechanism analysis suggested that the enhanced adsorption performance was due to the myriads of functional groups in PAO brushes that were easily accessible to metal ions because of the swelling of the polymer brushes in water. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48156.  相似文献   

16.
Bovine serum albumin imprinted polyethylene glycol 600 (PEG600) grafted Calcium alginate (CaA) hydrogel microspheres were prepared and characterized. The adsorption and recognition properties of PEG600 grafted calcium alginate (CaA-g-PEG600) microspheres were evaluated and the results showed that the crosslinking structure of CaA-g-PEG600 microspheres exerted an obvious effect on the adsorption capacity and imprinting properties for bovine serum albumin. The adsorption isotherms and recognition properties indicated that the imprinted modified microspheres had excellent rebinding affinity toward target proteins and the imprinting efficiency varied according to PEG600 grafting degree. The adsorption capacity and the imprinting factor were 5.5 mg g?1 and 3.6, respectively. Adsorption kinetics of CaA-g-PEG600 microspheres in accordance with the molecular weight between crosslinks (Mc) was investigated and the structural influence on protein selective rebinding was discussed. Furthermore, the binary solution separation performance of CaA-g-PEG600 microspheres with different Mc was investigated by selective binding bovine serum albumin from protein mixture solution.  相似文献   

17.
The preparation of indole molecularly imprinted polymers (indole‐MIPs) using 4‐vinylpyridine as functional monomer, silica gel as matrix were used to adsorb indole from fuel oil specifically. The reverse atom transfer radical polymerization (RATRP) technology was introduced to prepare the surface molecularly imprinted polymers, and the precipitation polymerization was adopted in the preparation process. The obtained indole‐MIPs were characterized by nitrogen adsorption, Fourier transform infrared spectrometry and scanning electron microscopy. The results show that indole‐MIPs were provided with the larger surface areas and more pores. The adsorption capacity of indole‐MIPs was 31.80 mg g?1 at 298 K, and the adsorption equilibrium was reached in a short time. The adsorption process was spontaneous by thermodynamic analysis, and an appropriate decrease in temperature could enhance the adsorption capacity. The adsorption process obeyed pseudo‐second‐order kinetic model by kinetics analysis. The isotherm analysis results show that both Langmuir and Sips equations were suitable to experimental data. The selective adsorption and reusable performance of indole‐MIPs were favorable. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40473.  相似文献   

18.
Two molecularly imprinted polymers (MIPs) – poly(methacrylic acid‐co‐TRIM) (TRIM, trimethylolpropanetrimethacrylate) and poly(acylamide‐co‐TRIM) – were synthesized in different solvents for the selective recovery of isovaleric acid (template) generated during the anaerobic digestion process. The chemical and structural characterizations of the synthetic adsorbent were carried out by Fourier transform infrared spectroscopy, TGA and porosimetry through N2 adsorption–desorption isotherms. The selective and adsorptive performances of the imprinted polymers were evaluated by kinetic, isothermal, thermodynamic and selectivity studies and by adsorbent reuse experiments. The poly(methacrylic acid‐co‐TRIM) synthesized with dimethyl sulfoxide:chloroform presented higher selectivity and adsorption capacity for isovaleric acid in the presence of six volatile fatty acids. The kinetic results were well adjusted to the pseudo‐nth order and intraparticle diffusion models, leading to k values of 10?4 and 6 × 10?5 for the best synthesis of MIPs and not‐imprinted polymers, respectively. Moreover, the Sips model best described the adsorption isotherm and generated a maximum adsorption capacity of ca 209 mg g?1 (at 25 °C). Cycles of MIP use–desorption–reuse indicated that the selective adsorbent performed better than commercial adsorbents, losing less than 3% of adsorption capacity after three cycles. © 2018 Society of Chemical Industry  相似文献   

19.
Cu+-containing materials have great potentials in various applications like adsorptive desulfurization. Nevertheless, their applications are severely obstructed by poor stability of Cu+ in air. Here, we first clarify the mechanism of Cu+ oxidation by first-principle calculations and demonstrate that moisture accelerates Cu+ oxidation dramatically. Then, the microenvironment of Cu2O-modified HKUST-1, a typical metal-organic framework, is adjusted from hydrophilic to hydrophobic with polydimethylsiloxane coating (producing Cu2O@HK@P). This isolates moisture from pores and enhances the stability of Cu+ significantly even under oxygen atmosphere. Cu+ in Cu2O@HK@P preserves well after exposed to air for 6 months, while Cu2O@HK lose almost all Cu+ for 2 weeks. The optimal Cu2O@HK@P can remove 540 μmol g−1 of thiophene from hydrous fuel, which is much superior to Cu2O@HK (227 μmol g−1) and most reported adsorbents. Our strategy can also be applied to stabilize Cu+ in various materials including zeolite, mesoporous silica, and activated carbon.  相似文献   

20.
Porous polymeric beads were obtained by the suspension polymerization of 2‐hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethacrylate (EGDMA). Poly(HEMA–EGDMA) beads were characterized by surfacearea measurements, swelling studies, FTIR, scanning electron microscopy (SEM), and elemental analysis. Poly (HEMA–EGDMA) beads had a specific surface area of 56 m2/g. SEM observations showed that the poly(HEMA–EGDMA) beads abounded macropores. Poly(HEMA–EGDMA) beads with a swelling ratio of 55%, and containing different amounts of Reactive Red 120 (9.2–39.8 μmol/g) were used in the adsorption/desorption of human serum albumin (HSA) from aqueous solutions and human plasma. The nonspecific adsorption of HSA was very low (0.2 mg/g). The maximum HSA adsorption amount from aqueous solution in phosphate buffer was 60.1 mg/g at pH 5.0. Higher HSA adsorption value was obtained from human plasma (up to 95.7 mg/g) with a purity of 88%. The equilibrium monolayer adsorption amount, Qmax was determined as 172.4 mg/g. The dimensionless separation factor (RL) value shows that the adsorption behavior of HSA onto the Reactive Red 120 attached poly(HEMA–EGDMA) beads was favorable (0 < RL < 1). Desorption of HSA from Reactive Red 120 attached poly (HEMA–EGDMA) beads was performed using 0.1M Tris/HCl buffer containing 0.5M NaCl. It was observed that HSA could be repeatedly adsorbed and desorbed with Reactive Red 120‐attached poly(HEMA–EGDMA) beads without significant loss in the adsorption amount. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   

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