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Acid Orange (acid + orange)
Selected AbstractsSeparation of dyes using composite carbon membranesAICHE JOURNAL, Issue 7 2009Sonny Sachdeva Abstract A composite, clay supported carbon membrane has been synthesized by carbonization of a blend of polyethylene glycol and phenol formaldehyde resin and the membrane thus obtained is characterized by separation of dyes. This membrane is subjected to permeability test using pure water which is found to be considerably higher than that reported in literature. It is subsequently shown to reject Acid Orange 7 dye from water with the rejection dependent on pressure and concentration of the dye which is typical phenomenon observed for a charged membrane. The separation data has been analyzed using the Space charge model and the membrane charge is estimated by minimizing the root mean square error between the experimental results and those calculated from the model. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Reactive azo dye reduction by Shewanella strain J18 143BIOTECHNOLOGY & BIOENGINEERING, Issue 4 2006Carolyn I. Pearce Abstract A bacterial isolate designated strain J18 143, originally isolated from soil contaminated with textile wastewater, was shown to reduce intensely coloured solutions of the reactive azo dye, Remazol Black B to colourless solutions. Phylogenetic placement based on 16S rRNA gene sequence homology identified the bacterium as a Shewanella species. Based on results from analyses of the end products of dye decoloration of Remazol Black B and the simpler molecule, Acid Orange 7, using capillary electrophoresis, UV,visible spectrophotometry and liquid chromatography-mass spectrometry, we suggest that colour removal by this organism was a result of microbially mediated reduction of the chromophore in the dye molecules. Anaerobic dye reduction by Shewanella strain J18 143 was 30 times more efficient than the reduction carried out by aerated cultures. Whole cells used a range of electron donors for dye reduction, including acetate, formate, lactate, and nicotinamide adenine dinucleotide (NADH), with formate being the optimal electron donor. The impact of a range of process variables was assessed (including nitrate, pH, temperature, substrate concentration, presence of an extracellular mediator) and results suggest that whole cells of Shewanella J18 143 offer several advantages over other biocatalysts with the potential to treat azo dyes. © 2006 Wiley Periodicals, Inc. [source] Photopolymerization of alicyclic methacrylate hydrogels for controlled releasePOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 7 2009Jing Han Abstract Alicyclic hydroxy methacrylate monomer, o -hydroxycyclohexyl methacrylate (HCMA), was synthesized and characterized by Fourier transformed infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance spectroscopy (1H-NMR). Photopolymerization kinetics of HCMA was investigated via real-time infrared spectroscopy (RT-IR). Polymeric network hydrogels based on hydroxyethyl methacrylate (HEMA) and HCMA were prepared by using the photopolymerization technique. Mechanical strength, swelling characteristic, and controlled release behavior of hydrogels with various feed compositions were studied. Poly(HEMA-co-HCMA) hydrogel had higher storage modulus than that of poly(HEMA) hydrogel as investigated by dynamic mechanical analysis (DMA). Acid orange 8 was used as a model drug for the investigation of drug release behavior of copolymeric hydrogels. Results indicated that increase in HCMA ratio in hydrogel composition could reduce the swelling rate and prolong the release time. Scanning electron microscopy (SEM) was also utilized to study the surface morphology of hydrogels, and the results indicated that HCMA content influenced pore diameter on the hydrogel surface. Copyright © 2008 John Wiley & Sons, Ltd. [source] DBD regeneration of GAC loaded with acid orange 7ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2009Guang-Zhou Qu Abstract Activated carbon (AC) has been widely used as adsorbent in various industrial applications, such as purification of water in sewage facilities and filtration of air in toxicity-treating factories. However, after exhaustion, AC should be regenerated and reused because of the limited resources for AC production and additional secondary pollution of spent-carbon dumped into water or soil. In this study, a process for regenerating AC based on high active species (O3, ·OH, HO2, O2, ·RO, etc.) generated by dielectric barrier discharge (DBD) oxidation was proposed. The regeneration of granular-activated carbon (GAC) exhausted with azo dye acid orange 7 was investigated to assay this method. The influences of the parameters, such as treatment time, electric field and gas kind, on the readsorption rate were studied systematically. The results of structural properties of GAC analyses showed that the surface area, the micropore area, external surface area, micropore volume and total volume of GAC after three cycles DBD treatment decreased to different extent. The adsorption isotherms indicated that the regeneration efficiency was about 81% after three times DBD plasma regeneration cycles, which confirmed the reuse feasibility of the regenerated GAC. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] | ||||||||||