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Monodisperse poly (methyl acrylate-meth-acyloxy-ethyl trimethylammonium chloride) cationic nanospheres were synthesized by soap-free emulsion polymerization, and were subsequently combined with gardenia to prepare dye/nanospheres. The influence of the concentration of gardenia yellow, rate of vortexing, temperature and pH of mixing on the adsorption capacity and stability of microspheres were thoroughly investigated, and the prepared gardenia/poly (methyl acrylate-meth-acyloxy-ethyl trimethylammonium chloride) nanospheres acted as liquid pigments to dye the fabric substrates by the impregnation method. In particular, the photostability of gardenia/poly (methyl acrylate-meth-acyloxy-ethyl trimethylammonium chloride) and the reflection of its dyed fabrics are distinctly described, the comparison of the dyeing property effect between gardenia/poly (methyl acrylate-meth-acyloxy-ethyl trimethylammonium chloride) and gardenia yellow dyed by mordant dyeing were analyzed. According to the experimental findings, the dyestuff nanospheres have high stability when the pH is 7–8, the mass ratio of gardenia yellow to poly (methyl acrylate-meth-acyloxy-ethyl trimethylammonium chloride) nanospheres was 12.8:1, the temperature was 60°C for 30 min, and the mixing speed was 500 rpm. Dyeing cotton fabrics with gardenia/poly (methyl acrylate-meth-acyloxy-ethyl trimethylammonium chloride) produced higher color strength and color fastness than the gardenia yellow with mordant dyeing. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel and cheap adsorbent with high adsorption capacity for NO was developed. • It can operate under excess O 2 at low temperature without additional reducing agents. • Denitrification was obviously enhanced in two-stage fixed-bed reactor. • The energy efficiency was 14 times higher than that of direct decomposition method. • It shown superior resistance to SO 2 , CO 2 and H 2 O. It is a great challenge to achieve high efficiency and low energy consumption denitrification without adding reducing agent at low temperature. Herein, we developed MgCo 2 O 4 -BaCO 3 /AC carbon-based composites as novel and cheap adsorbents with high adsorption capacity to fill the first section of two-stage fixed-bed reactor to form adsorption bed, and MgCo 2 O 4 -40%BaCO 3 as catalyst was filled in the second section as catalyst bed. Significantly, under the condition of excess O 2 , the adsorption capacity of 20%MC-0.5Ba/AC for NO was as high as 40.2 mg/g, and the conversion of adsorbed NO was as high as 99.7% under microwave irradiation at 250 °C. The denitrification efficiency of the two-stage fixed bed reactor was much higher than that of the one-stage fixed bed reactor. The energy efficiency of adsorption-decomposition method was 14 times higher than that of direct decomposition method. Interestingly, the activated carbon was not consumed during the whole reaction process, so no secondary pollution such as CO and CO 2 was produced. More importantly, despite the presence of SO 2 , CO 2 or H 2 O in the inlet gas, 20%MC-0.5Ba/AC still showed excellent adsorption capacity for NO, and the absorbed NO could be successfully decomposed, demonstrating excellent resistance to SO 2 , CO 2 and H 2 O. This work presents a new route for denitrification technology with high efficiency, low energy consumption and no secondary pollution, and provides guidance for rational design of adsorbents with high adsorption capacity for NO. [ABSTRACT FROM AUTHOR]

Shorea sawdust grafted with poly(acrylic acid) (SD-g-PAA) is synthesized and characterized as an adsorbent of toxic organic compounds. SD-g-PAA copolymers are prepared using Fenton’s reagent (Fe+2–H2O2) as the redox initiator. The graft copolymerization is examined to determine the effects of temperature, concentrations ofand H2O2(aq), and AA/SD ratio. The obtained maximum grafting percentage of the grafted copolymer is 13.0 ± 0.2%. The grafted copolymer is characterized using Fourier transform infrared spectroscopy and solid-state13C NMR. A representative SD-g-PAA copolymer is neutralized to a sodium salt (SD-g-PANa) and used in the adsorption of malachite green (MG), methyl violet (MV), and paraquat (PQ). The monolayer adsorption capacities of these substances are 233.7, 312.9, and 164.8 mg/g adsorbent, respectively. The high adsorption capacity of SD-g-PANa for toxic matter indicates its potential in the treatment of wastewater that contains MG, MV, or PQ. [ABSTRACT FROM PUBLISHER]

Chitin-grafted-poly(methacrylic acid) (chi- g-PMAA) was synthesized and characterized as an adsorbent of paraquat. Chi- g-PMAA copolymers were prepared using various concentrations of ammonium cerium(IV) nitrate (Ce+4) to determine the optimal concentration of Ce+4. Grafting was verified by differential scanning calorimeter thermograms, FTIR, and solid-state 13C-NMR spectra. A representative chi- g-PMAA copolymer was neutralized to a sodium salt (chi- g-PMANa) and used to adsorb paraquat. The adsorption equilibrium data are strongly related to both the Langmuir and the Freundlich isotherms. The maximal adsorption capacity is 147.0 mg/g-adsorbent. This value exceeds those of Fuller's earth and activated carbon, which are the most common binding agents that are currently used for paraquat. The results suggest that chi- g-PMANa has potential as a paraquat adsorbent. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012 [ABSTRACT FROM AUTHOR]

Abstract: This work investigates the adsorption of paraquat from aqueous medium using a methacrylic acid (MAA)-modified rice husk. The carboxyl groups were chemically bound to the surface of the rice husk by graft copolymerization using Fenton’s reagent as a redox initiator. The graft copolymerization was examined to determine the H2O2 concentration and the amount of MAA monomer used. FT-IR spectra confirmed the presence of carbonyl groups on the structural units of the rice husk derivative. The MAA-modified rice husks were hydrolyzed to sodium salt and used to adsorb paraquat. The adsorption was rapid in the first few minutes and quickly reached equilibrium. Equilibrium adsorption data are more consistent with the Langmuir isotherm equation than with the Freundlich equation. The maximum adsorption capacity of modified rice husks was 317.7mg/g-adsorbent. This value clearly exceeds the 60mg/g of Fuller’s earth and the 90mg/g of activated carbon, which are the most commonly used binding agents for paraquat. [Copyright &y& Elsevier]

Abstract: Chitin grafted poly (acrylic acid) (chi-g-PAA) is synthesized and characterized as an adsorbent of toxic organic compounds. Chi-g-PAA copolymers are prepared using of ammonium cerium (IV) nitrate (Ce4+) as the initiator. The highest grafting percentage of AA in chitin obtained using the traditional technique is 163.1%. A maximum grafting percentage of 230.6% is obtained using central composite design (CCD). Experimental results are consistent with theoretical calculations. The grafted copolymer is characterized by Fourier transform Infrared spectroscopy and solid state 13C NMR. A representative chi-g-AA copolymer is hydrolyzed to a type of sodium salt (chi-g-PANa) and used in the adsorption of malachite green (MG), methyl violet (MV), and paraquat (PQ) in aqueous. The monolayer adsorption capacities of these substances are 285.7, 357.1, and 322.6mg/g-adsorbent, respectively. Thermodynamic calculations show that the adsorption of MG, MV, and PQ are more favored at diluted solutions. The high adsorption capacity of chi-g-PANa for toxic matter indicates its potential in the treatment of wastewater and emergency treatment of PQ-poisoned patients. [Copyright &y& Elsevier]

Abstract: Methacrylic acid (MAA) grafted rice husk was synthesized using graft copolymerization with Fenton''s reagent as the redox initiator and applied to the adsorption of paraquat. The highest grafting percentage of 44.3% was obtained using the traditional kinetic method. However, a maximum grafting percentage of 65.3% was calculated using the central composite design. Experimental results based on the recipes predicted from the statistical analysis are consistent with theoretical calculations. A representative polymethacrylic acid-g-rice husk (PMAA-g-rice husk) copolymer was hydrolyzed to a salt type and applied to the adsorption of paraquat. The adsorption equilibrium data correlate more closely with the Langmuir isotherm than with the Freundlich equation. The maximum adsorption capacity of modified rice husk is 292.5mg/g-adsorbent. This value exceeds those for Fuller''s earth and activated carbon, which are the most common binding agents used for paraquat. The samples at various stages were characterized by solid-state 13C NMR spectroscopy. [Copyright &y& Elsevier]