Effect of low‐temperature plasma and chitosan treatment on wool dyeing with Acid Red 27

This study examines in detail the influence of low‐temperature plasma and biopolymer chitosan treatments on wool dyeability. Wool knitted fabrics were treated and characterized by whiteness and shrink‐resistance measurements. Surface modification was assessed by contact‐angle measurements of human hair fibers, which were used as a model to study the wetting properties of the treated wool knitted fabrics. The dyeing behavior was assessed from the diffusion mechanism point of view. The dyeing kinetics were measured at two different pHs (4.2 and 6.5) and three different temperatures (60, 85, and 100°C) to gain information about the contribution of the surface modification treatment to the dyeing mechanism. The exhaustion and reflectance data were compared, and the apparent diffusion coefficients were calculated. On the basis of the obtained results, a model for the dyeing mechanism of the chitosan treated wool was proposed. When treated with chitosan, the polymer sheath spread on the surface of the fibers acted as a predominant dyeing site in very short dyeing times, thus interacting with the dye and in later stages imparting the dye to the wool fiber. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2204–2214, 2005     

甲壳素/壳聚糖在废水处理中的应用

综述了甲壳素和壳聚糖在含重金属离子废水、有色废水、食品加工废水和生活污水强化生物处理中的应用现状，认为甲壳素和壳聚糖是高效的生物吸附剂和絮凝剂，有颦在水处理领域获得更加广泛的应用。     

Preparation of betaine‐modified cationic cellulose and its application in the treatment of reactive dye wastewater

Betaine‐modified cationic cellulose was prepared through the reaction of cellulose with betaine hydrochloride by an efficient one‐step dry method. Dicyandiamide was used as a dehydrating agent to promote the formation of ester bonds between the reactants. Fourier transform infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy were used to characterize the cellulose betainate. Experiments showed that at a molar ratio of the cellulose glucose unit, betaine hydrochloride to dicyandiamide, of 1:1:0.5 at 150°C for 3 h, the degree of substitution of the cationic group reached 0.80. The adsorption of simulated C. I. Reactive Red 24 and C. I. Reactive Red 195 wastewater on the cationic cellulose was carried out, and the effects of the adsorbent dose, initial dye concentration, and salt concentration on the dye removal efficiency were investigated. The equilibrium adsorption isotherm data of the cationic cellulose exhibited a better fit to the Langmuir isotherm model than the Freundlich one. The experimental results suggest that the prepared cationic cellulose materials show potential application for reactive dye wastewater treatment. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40522.     

壳聚糖树脂在废水处理中的应用研究进展

综述了壳聚糖树脂在处理重金属离子废水、染料废水和其他废水的研究应用,总结了壳聚糖树脂处理废水的作用机理及其解吸、再利用方法.     

Oxygen diffusivity in alginate/chitosan microcapsules

BACKGROUND: Oxygen diffusion properties affect the proliferation and metabolism of cells cultured in microcapsules with a polyelectrolyte complex membrane. The effective diffusion coefficient (De) of oxygen in alginate/chitosan (AC) microcapsules under different preparation conditions was calculated, and a mathematic model was developed to investigate the effect of oxygen diffusion on cell loading in the microcapsules. RESULTS: Oxygen De in AC microcapsules was independent of alginate solution concentration, intrinsic viscosity of alginate and different polyelectrolyte complex membranes. De decreased from 2.1 ± 0.3 × 10^?9 to 0.17 ± 0.01 × 10^?9 m² s^?1 as microcapsule diameter decreased from 1800 to 45 0 µm. Microcapsule density was increased from 1.013 ± 0.000 to 1.034 ± 0.003 g mL^?1 as diameter decreased from 1775 to 430 µm. The mathematic model results showed that critical CHO cell loadings were 1.8 × 10⁸ or 1.1 × 10⁸ cells mL^?1 in microcapsules with 450 or 1800 µm diameter, respectively. CONCLUSIONS: No significant difference was found of oxygen De between calcium alginate beads and AC microcapsules. The decrease of De with diameter was attributed to the increasing density and compact degree on the surface. The model results indicated that risk on necrosis rose with the increasing diameter. Microcapsules with smaller diameters may have more advantages on cell culture. © 2012 Society of Chemical Industry     

Immobilization of hybridoma cells in chitosan alginate beads

A new method for immobilizing hybridoma cells using chitosan-stabilized calcium alginate beads was developed. The ionotropic gelation of chitosan and calcium with alginate resulted in the formation of highly cross-linked, porous beads that were mechanically and chemically stable in phosphate buffered medium. Hybridomas entrapped in these beads were cultured semi-continuously using periodic medium exchange. Viable population densities in the order of 5 × I0⁷ cells/mL were attained within the beads and up to two-fold increases in volumetric monoclonal antibody (MAb) productivity over batch suspension cultures were observed. Oxygen mass transfer limitations within the chitosan-alginate beads were evaluated by considering biokinetics and diffusive transport. Model equations were developed and used to evaluate the effect of bead diameter on the contained cells. The predictions were consistent with experimental observations of maximum viable population densities attained in beads of various size.     

Enhanced swelling and methylene blue adsorption of polyacrylamide‐based superabsorbents using alginate modified montmorillonite

Polyacrylamide/sodium alginate modified montmorillonite (PAM/SA‐MMT) superabsorbent composites were synthesized by free‐radical polymerization under normal atmospheric conditions. They were characterized by X‐ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy (FTIR). Their water absorbency and methylene blue (MB) adsorption behaviors were studied. Compared with PAM/MMT composites, PAM/SA‐MMT composites demonstrated greater water absorbency (863 g g^?1 in distilled water and 101 g g^?1 in 0.9 wt % NaCl solution) and higher adsorption capacity of 2639 mg g^?1 for MB. The adsorption behaviors of the composites showed that the isotherms and adsorption kinetics were in good agreement with the Langmuir equation and pseudo‐second‐order equation, respectively. FTIR analysis suggested that the MB adsorption of PAM/SA‐MMT composites via a mechanism combined electrostatic, H‐bonding and hydrophobic interaction. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40013.     

Thermogravimetric characterization of chitosan/alginate microparticles loaded with different drugs

Summary  The thermal behavior of several chitosan/alginate /drug microparticle formulations containing ciprofloxacin, ibuprofen, ketoprofen or tannic acid was investigated by thermogravimetry in inert atmosphere in the temperature range of 25 – 900^oC. The chemical composition and the method used for drug incorporation influenced the thermal stability of the products. It was found that the entrapment of the drug in chitosan, alginate or chitosan/alginate complex modifies the degradation mechanism introducing new degradation steps by comparison with raw polymers. The activation energy for the main degradation step is also changed.     

Textile with a hydrogel and iron oxide nanoparticles for wastewater treatment after reactive dyeing

In this work, we describe for the first time the synthesis of a hydrogel with iron oxide nanoparticles, uniformly distributed in its structure on a polyamide fabric by surface initiated photopolymerization. The type of outgoing iron ions Fe(II), Fe(III), and the combination between them influences the properties of the iron oxide particles and the obtained composite materials (PAF2, PAF3, and PAF32). All composite materials have been investigated as catalysts in heterogeneous Fenton process for treating real industrial wastewater after dyeing of cotton fabric with reactive dye Drimarene K-7B. Different conditions on the degradation of this dye have been investigated. The best result for discoloration has been obtained with PAF2 at concentration 9.4 g L⁻¹ and pH = 2.2 in the presence of H₂O₂ (93.3 mmol L⁻¹, where 78% of dye was degraded for 24 h and 90.5%-for 48 h. The high salinity of wastewaters, typical for dyeing with reactive dyes favors discoloration, while surface-active agents hinder the process. The obtained material is reusable and is more effective in less polluted water solutions. It has been found that the composite material can be used repeatedly.     

壳聚糖及其衍生物在水处理中的应用新进展

天然高分子聚合物壳聚糖具有原料丰富、无毒、易于生物降解等优点,在水处理方面的应用日益广泛,不断有新方法和新技术产生.综述了近几年来壳聚糖及其衍生物在含重金属离子废水,染料废水、食品工业废水和含酚废水处理中的应用新进展.     

Preparation and multifunctional application of meso‐chitosan for the woolen process

This study used chitosan deacetylated to different degrees to process woolen fabrics via the nanometrization of sodium hydroxide of different concentrations. The analysis and determination of the bacterial resistance, shrink resistance, Fourier transform infrared, and dyeability were then carried out for the processed substances. The particle diameter was measured with light scattering and scanning electron microscopy. It was then reduced with 5% and higher concentrations of NaOH, in which the particle diameter was 150–750 nm. As for bacterial resistance, the processed cloth that was not oxidized by H₂O₂ had better bactericidal and bacteriostatic effects than the cloth that underwent the oxidation process. Chitosan and meso‐chitosan had a bacterial‐resistance effect on the woolen fabrics. The processed cloth also had a better shrink‐resistance rate, but the effect of nanometrization was not obvious. For the dyeability of the woolen fabrics, meso‐chitosan was better than chitosan. The higher degree of deacetylation of chitosan slightly improved the dyeability. The dyeability increased a little as the temperature of the curing treatment rose and the time of the curing treatment was extended. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4080–4086, 2007     

Improving the colorfastness of poly(ethylene terephthalate) fabrics with the natural dye of Caesalpinia sappan L. Wood extract and the effect of chitosan and low-temperature plasma

The effect of a low-temperature plasma and/or chitosan pretreatment as a mordant on the dyeing of poly(ethylene terephthalate) fabrics with an aqueous extract of Caesalpinia sappan L. wood, which showed a remarkably high coloring property in a natural dyeing system, was investigated. After dyeing, scanning electron microscopy, add-on, color measurements, and fastness to washing tests were performed. Dyeing with the C. sappan L. extract led to fair-to-good fastness properties in conventional natural dyeing. The results clearly show that the pretreatment with chitosan and/or plasma is better than a metal mordant in terms of the dye uptake and reduction in the dyeing time, that the proposed pretreatment coloration reaction could be carried out without the need for repetitive dye steps, and that it prevents the excessive use of dye chemicals, thereby resulting in a more ecofriendly process. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Preparation and adsorption properties of diethylenetriamine‐modified chitosan beads for acid dyes

This work has demonstrated that the novel chitosan derivative, synthesized by phase transition and grafting diethylenetriamine, has a great potential for the adsorption of acid dyes from aqueous solutions. Four acid dyes with different molecular sizes and structures were used to investigate the adsorption performance of diethylenetriamine‐modified chitosan beads (CTSN‐beads). Results indicated that the adsorption of dyes on CTSN‐beads was largely dependent on the pH value and controlled by the electrostatic attraction. In addition, the adsorption rate (AO10 > AO7 > AR18 > AG25) and adsorption capacities (AO7 > AR18 > AO10 > AG25) were directly related to the molecular size of the dye and the amount of the sulfonate groups on the dye molecules. The equilibrium and kinetic data fitted well with the Langmuir–Freundlich and pseudo‐second‐order model. Furthermore, thermodynamic parameters indicated that the adsorption processes occurred spontaneously and higher temperature made the adsorption easier. The reuse tests indicated that the CTSN‐beads can be recovered for multiple uses. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4090–4098, 2013     

壳聚糖及其衍生物在工业污水处理中的研究及应用

介绍了近年来国内外壳聚糖及其衍生物在不同工业污水处理中的应用及相关机理.壳聚糖及其衍生物作为絮凝剂、金属离子的螯合剂以及有机物的吸附剂,在工业污水处理中有着相当广泛的应用,主要是絮凝和处理含重金属离子的工业废水,环境效益显著.壳聚糖及其衍生物是绿色的水处理剂,其未来发展的方向是合成性能更为优良的改性壳聚糖,与其他技术复合使用,并深入研究其对复杂工业废水的处理能力.     

壳聚糖及其衍生物的吸附性能及对含酚废水治理的应用

介绍了壳聚糖及其衍生物对废水中重金属、有机酸、染料和蛋白质等吸附性能的研究现状。阐述了含酚废水处理中各种常用的方法及其原理,并分析了这些技术的特点和存在的问题。探讨了以壳聚糖及其衍生物作为吸附剂处理含酚废水的现有研究,并提出了展望。     

Pseudo‐first‐order kinetic studies of the sorption of acid dyes onto chitosan

The adsorption of five acid dyes onto chitosan, derived through the deacetylation of crab‐shell chitin, from aqueous solutions was studied. The equilibrium isotherms were measured and analyzed with the Langmuir, Freundlich, and Redlich–Peterson equations; the results correlated well with the Langmuir equation. Kinetic studies were also performed in an agitated batch adsorber to study the effect of the initial dye concentration and the mass of chitosan. The kinetics were analyzed with the pseudo‐first‐order rate equation, and the rate constants were determined. The first‐order kinetic model correlated the experimental concentration and time data at short times and even up to 60% of the total adsorption period in a number of systems. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1633–1645, 2004     

Electrospun polymer of intrinsic microporosity fibers and their use in the adsorption of contaminants from a nonaqueous system

The smooth and uniform polymer of intrinsic microporosity (PIM‐1) fibers, which have high adsorption capacities toward organic contaminants from nonaqueous systems, were successfully obtained by electrospinning. According to the N₂ adsorption–desorption analysis, the surface area of the PIM‐1 fibers was higher than that of the PIM‐1 powder. The higher surface area of the fibers did not come from the interfiber pores but from intrafiber pores formed by the fast evaporation of the solvent in the electrospinning process. The PIM‐1 fibers had more mesopores than the PIM‐1 films. As a result, the adsorption rates of the dyes on the fibers were much higher than those on the dense films. We found that the adsorption data fitted perfectly with the pseudo‐second‐order model and intraparticle diffusion model. The adsorption mechanism between the dyes and PIM‐1 was π–π interaction. Therefore, the dye could be desorbed from PIM‐1 with toluene; this was a better π‐electron‐rich donor than the dye. In summary, we believe that the use of PIM‐1 fibers for organic solvent recovery is a green, sustainable, and efficient method, and they have a great potential for industrial applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43475.     

天然高分子絮凝剂在工业污水处理中的应用

研究了以天然高分子壳聚糖复配而成的新型高效复合絮凝剂在不同的工业污水处理中的应用,通过试验和现场应用．确定了该壳聚糖复合絮凝剂在几种典型工业污水处理中的最佳工艺路线、pH和最佳处理配方,以及处理后的相关的技术经济指标。结果表明,该絮凝剂与传统的絮凝剂相比,COD,SS及金属离子的去除率均可提高10％～20％．成本下降40%～60％,且二次污染大大减少,具有明显的经济效益和环境效益。     

Feldspar/titanium dioxide/chitosan as a biophotocatalyst hybrid for the removal of organic dyes from aquatic phases

Feldspar/titanium dioxide/chitosan hybrid, a photoactive biocompatible adsorbent for anionic dyes, was synthesized, characterized, and successfully tested. The adsorbent characterization, pH role, adsorbent dose effect, equilibrium data, kinetic plats, and thermodynamic parameters are reported. The point of zero charge for the hybrid was measured to be 8.3, and the most favorable pH range for the adsorption process was found to be below this pH value. The adsorption equilibrium study demonstrated that the Freundlich model was best fitted to the experimental data. Without UV light exposure, the prepared adsorbent adsorbed 72 mg of Acid Black 1 (AB1)/g of sorbent (86% removal) from a 100‐mL solution with an initial dye concentration of 50 mg/L, whereas UV irradiation resulted in an increase in the elimination of AB1 dye (97% removal). The kinetic data was depicted well by the pseudo‐second‐order model. The thermodynamic parameters indicated that the reaction between the hybrid and the dye was exothermic and also spontaneous at lower temperatures. In the batch desorption process, several aqueous solutions adjusted to different pH values were tested, and the best desorption performance (90% desorption) was achieved at pH 11. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40247.