scholarly journals Recycling food waste to clean water: the use of a biodigester's residual liquid inoculum (RLI) to decolourise textile azo dyes

2017 ◽  
Vol 77 (2) ◽  
pp. 398-408 ◽  
Author(s):  
A. C. Maganha de Almeida ◽  
J. Backhaus ◽  
C. R. Corso
Keyword(s):  
Food Waste ◽  
Azo Dyes ◽  
Room Temperature ◽  
Residual Liquid ◽  
Colour Removal ◽  
Prolonged Incubation ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Ir Analysis ◽  
Dye Solutions

Abstract A residual liquid inoculum (RLI) was used to decolourise solutions of Acid Yellow 25 (AY25) and Direct Violet 51 (DV51) azo dyes. The RLI was obtained through anaerobic digestion of food waste from a university restaurant. The concentration of bacteria in the RLI was 8.45 × 107 CFU mL−1. Dye solutions (50 μg mL−1) were inoculated with the RLI (20% v/v) and incubated at room temperature. The decolourisation studies took place at microaerophilic and in-batch conditions and at pH = 2.50. Initially, the dyes were taken up from solution by biosorption; maximum colour removal was achieved after 3 hours of incubation, with 88.66% for AY25 and 77.65% of DV51. At prolonged incubation times (3–96 hours) decolourisation was mainly attributed to biodegradation of the azo solutions, with breakage of the azo bond, as detected by UV-VIS spectroscopy and Fourier transform infrared (FT-IR) analysis. Analysis of UV-VIS absorption rates of dyes showed, however, that AY25 was more readily biodegradable whereas DV51 was more recalcitrant to the action of the RLI.

The role of platinum on the NOx storage and desorption behavior of ceria: An online FT-IR study combined with in situ Raman and UV-Vis spectroscopy

2020 ◽  
Author(s):  
Anastasia Filtschew ◽  
Pablo Beato ◽  
Søren Birk Rasmussen ◽  
Christian Hess
Keyword(s):  
Gas Phase ◽  
Phase Analysis ◽  
Room Temperature ◽  
Storage Mechanism ◽  
In Situ Raman ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Ir Study

The role of platinum on the room temperature NOx storage mechanism and the NOx desorption behavior of ceria was investigated by combining online FT-IR gas-phase analysis with in situ Raman...

Kinetics of azoreductase and assessment of toxicity of metabolic products from azo dyes by Pseudomonas luteola

2001 ◽  
Vol 43 (2) ◽  
pp. 261-269 ◽  
Author(s):  
T.-L. Hu
Keyword(s):  
Azo Dyes ◽  
Competitive Inhibition ◽  
Orthanilic Acid ◽  
Metabolic Products ◽  
Before And After ◽  
Ft Ir ◽  
Ir Analysis ◽  
Pseudomonas Luteola ◽  
Monoazo Dyes ◽  
Kinetics Of

This is a continuous study on a decolorization strain, Pseudomonas luteola, which involves treating seven azo dyes with different structures. This study focuses mainly on determining both the mechanism of decolorization by P. luteola and the activity of azoreductase from P. luteola as well as identifying and assessing the toxicity of metabolic products of azo dyes. The growth of P. luteola reached the stationary phase after shaking incubation for 24 hours. Then, while being kept static, the color of seven tested azo dyes (100 mg/l) could be removed. The proportion of color removal was between 59–99%, which figure is related to the structure of the dye. Monoazo dyes (RP2B, V2RP and Red 22) showed the fastest rate of decolorization, i.e. from 0.23–0.44 mg dye-mg cell–1 hr–1. P. luteola could remove the color of V2RP and a leather dye at a concentration of 200 mg/l, and as to the rest of the azo dyes, it could remove at a concentration of up to 100 mg/l. Decolorization of RP2B and Red 22 required activation energy of 7.00 J/mol and 6.63 J/mole, respectively, indicating that it was easier for azoreductase to decolorize structurally simple dyes. The kinetics of azoreductase towards seven azo dyes suggested a competitive inhibition model be applied. Microtox® was used to analyze the toxicity of the metabolic products of azo dyes. EC50 showed differences in toxicity before and after the azo dyes had been metabolized. Analysis revealed significant differences between the results obtained by EC50 with Blue 15 and those obtained with the leather dye, indicating that the toxicities of the metabolic products were increased. The differences obtained by EC50 with Red 22, RP2P and V2RP were small, and Black 22 showed no such difference. Sulfanic acid and orthanilic acid may be the intermediate products of Violet 9 and RP2B, respectively. However, according to FT-IR analysis, aromatic amines were present in the metabolic product.

scholarly journals ABOUT THERMAL STABILITY OF BISMUTH(III) IODINE ETIOPORPHYRIN II COMPLEX

2017 ◽  
Vol 12 (1) ◽  
pp. 26-30 ◽  
Author(s):  
D. V. Golubev ◽  
V. D. Rumyantseva ◽  
V. V. Fomichev
Keyword(s):  
Room Temperature ◽  
Complex Geometry ◽  
Basis Set ◽  
Prepared Compound ◽  
Intense Line ◽  
Relativistic Approximation ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
First Time ◽  
Thermal Stability Of

For the first time, a complex of bismuth(III) with iodine and etioporphyrin II is reported. It was prepared by reacting etioporphyrin II and bismuth(III) iodide in pyridine in Ar atmosphere. The prepared compound was characterized by FT-IR, 1H-NMR, UV-VIS spectroscopy and mass spectrometry. One intense line at m/z 684.990 attributed to the complex without the iodine atom is observed in the mass spectrum. This is in agreement with the data indicating that bismuthporphyrin complexes generally have low stability. Analysis of FT-IR spectra obtained at room temperature and at 145°С is reported. Priroda15 DFT package was used for optimization of complex geometry and calculation of the IR spectrum. Calculations were done using BPE functional and L1 basis set under relativistic approximation of Dyall Modified Dirac. Assignment of the vibrational frequencies is reported. Collected data indicate that the complex of bismuth(III) with iodine and etioporphyrin II is not stable and easily hydrolyses when exposed to air forming the corresponding hydroxocomplex. This transformation does not change significantly the dynamics of the porphyrin ring.

Synthesis of Zinc Phthalocyanine and its Dimerization in DMF

2014 ◽  
Vol 926-930 ◽  
pp. 270-273
Author(s):  
Zhen Hua Cheng ◽  
Na Cui ◽  
Hong Xiao Zhang ◽  
Li Jun Zhu ◽  
Dao Hong Xia
Keyword(s):  
Sem Analysis ◽  
Red Shift ◽  
Zinc Phthalocyanine ◽  
Dimethyl Formamide ◽  
Improved Method ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Ir Analysis ◽  
High Yields ◽  
Maximum Absorption Wavelength

Zinc phthalocyanine was prepared with improved method with high yields and characterized by XRD and FT-IR analysis. The SEM analysis was also conducted to demonstrate the apparent morphology of the synthesized compound. Dimerization of the zinc phthalocyanine was measured by UV-Vis spectroscopy in N, N-dimethyl formamide (DMF). The red–shift of maximum absorption wavelength and deviation from Lambert-Beer law was observed with increasing the concentration.

Curing Process of Epoxy Resin Using Low Molecular Polyamide 651 as Curing Agent

2014 ◽  
Vol 936 ◽  
pp. 63-66 ◽  
Author(s):  
Chun Hua Han ◽  
Lin Wang ◽  
Dong Yu Zhao
Keyword(s):  
Epoxy Resin ◽  
Room Temperature ◽  
Curing Agent ◽  
Curing Process ◽  
Curing Conditions ◽  
Temperature Spectra ◽  
Infrared Spectral ◽  
Ft Ir ◽  
Ir Analysis ◽  
Epoxy Groups

In this paper low molecular polyamide 651(PA651) is used as the curing agent of epoxy resin. The optimum curing conditions and dosage of the curing agent are obtained by DMA and FT-IR analysis. Based on the dynamic mechanical temperature spectra of samples test, the best curing conditions are room temperature 2 hours, 70°C 2 hours, 125°C 2.5 hours and 150°C 1 hours (RT / 2 h + 70 °C / 2 h +125°C / 2.5 h + 150 °C / 1 h). The best dosage of curing agent PA651 is 50 wt %. Since the analysis of Fourier Infrared spectral verified that epoxy groups react completely, the curing conditions are the best curing process.

Polarized microbeam FT-IR analysis of single fibers

1996 ◽  
Vol 54 ◽  
pp. 206-207
Author(s):  
Liling Cho ◽  
David L. Wetzel
Keyword(s):  
Molecular Orientation ◽  
Transition Point ◽  
Polymer Fibers ◽  
Single Fiber ◽  
Wire Grid ◽  
Polyester Fibers ◽  
Ft Ir ◽  
Ir Analysis ◽  
The Relationship ◽  
Wire Grid Polarizer

Polarized infrared microscopy has been used for forensic purposes to differentiate among polymer fibers. Dichroism can be used to compare and discriminate between different polyester fibers, including those composed of polyethylene terephthalate that are frequently encountered during criminal casework. In the fiber manufacturering process, fibers are drawn to develop molecular orientation and crystallinity. Macromolecular chains are oriented with respect to the long axis of the fiber. It is desirable to determine the relationship between the molecular orientation and stretching properties. This is particularly useful on a single fiber basis. Polarized spectroscopic differences observed from a single fiber are proposed to reveal the extent of molecular orientation within that single fiber. In the work presented, we compared the dichroic ratio between unstretched and stretched polyester fibers, and the transition point between the two forms of the same fiber. These techniques were applied to different polyester fibers. A fiber stretching device was fabricated for use on the instrument (IRμs, Spectra-Tech) stage. Tension was applied with a micrometer screw until a “neck” was produced in the stretched fiber. Spectra were obtained from an area of 24×48 μm. A wire-grid polarizer was used between the source and the sample.

Seed-mediated synthesis and PEG coating of gold nanoparticles for controlling morphology and sizes

MRS Advances ◽  
2020 ◽  
Vol 5 (63) ◽  
pp. 3353-3360
Author(s):  
Susana Helena Arellano Ramírez ◽  
Perla García Casillas ◽  
Christian Chapa González
Keyword(s):  
Gold Nanoparticles ◽  
Polyethylene Glycol ◽  
Room Temperature ◽  
Colloidal Stability ◽  
Infrared Spectrometry ◽  
Ammonium Bromide ◽  
Chloroauric Acid ◽  
Vis Spectroscopy ◽  
Seed Mediated ◽  
Peg Coating

AbstractA significant area of research is biomedical applications of nanoparticles which involves efforts to control the physicochemical properties through simple and scalable processes. Gold nanoparticles have received considerable attention due to their unique properties that they exhibit based on their morphology. Gold nanospheres (AuNSs) and nanorods (AuNRs) were prepared with a seed-mediated method followed of polyethylene glycol (PEG)-coating. The seeds were prepared with 0.1 M cetyltrimethyl-ammonium bromide (CTAB), 0.005 M chloroauric acid (HAuCl4), and 0.01 M sodium borohydride (NaBH4) solution. Gold nanoparticles with spherical morphology was achieved by growth by aggregation at room temperature, while to achieve the rod morphology 0.1 M silver nitrate (AgNO3) and 0.1 M ascorbic acid solution were added. The gold nanoparticles obtained by the seed-mediated synthesis have spherical or rod shapes, depending on the experimental conditions, and a uniform particle size. Surface functionalization was developed using polyethylene glycol. Morphology, and size distribution of AuNPs were evaluated by Field Emission Scanning Electron Microscopy. The average size of AuNSs, and AuNRs was 7.85nm and 7.96 x 31.47nm respectively. Fourier transform infrared spectrometry was performed to corroborate the presence of PEG in the AuNPs surface. Additionally, suspensions of AuNSs and AuNRs were evaluated by UV-Vis spectroscopy. Gold nanoparticles were stored for several days at room temperature and it was observed that the colloidal stability increased once gold nanoparticles were coated with PEG due to the shield formed in the surface of the NPs and the increase in size which were 9.65±1.90 nm of diameter for AuNSs and for AuNRs were 29.03±5.88 and 8.39±1.02 nm for length and transverse axis, respectively.

Green synthesis of mixed metallic nanoparticles using room temperature self-assembly

2017 ◽  
Vol 13 (2) ◽  
pp. 4671-4677 ◽  
Author(s):  
A. M. Abdelghany ◽  
A.H. Oraby ◽  
Awatif A Hindi ◽  
Doaa M El-Nagar ◽  
Fathia S Alhakami
Keyword(s):  
Self Assembly ◽  
Metallic Nanoparticles ◽  
Room Temperature ◽  
Bimetallic Nanoparticles ◽  
Reduction Process ◽  
Nano Particles ◽  
Nano Structure ◽  
Small Shift ◽  
Molar Ratios ◽  
Vis Spectroscopy

Bimetallic nanoparticles of silver (Ag) and gold (Au) were synthesized at room temperature using Curcumin. Reduction process of silver and gold ions with different molar ratios leads to production of different nanostructures including alloys and core-shells. Produced nanoparticles were characterized simultaneously with FTIR, UV/vis. spectroscopy, transmission electron microscopy (TEM), and Energy-dispersive X-ray (EDAX). UV/vis. optical absorption spectra of as synthesized nanoparticles reveals presence of surface palsmon resonance (SPR) of both silver at (425 nm) and gold at (540 nm) with small shift and broadness of gold band after mixing with resucing and capping agent in natural extract which suggest presence of bimetallic nano structure (Au/Ag). FTIR and EDAX data approve the presence of bimetallic nano structure combined with curcumin extract. TEM micrographs shows that silver and gold can be synthesized separately in the form of nano particles using curcumin extract. Synthesis of gold nano particles in presence of silver effectively enhance and control formation of bi-metallic structure.

Synthesis and Evaluation of Levulinic Ester as Biodiesel Additives

2020 ◽  
Vol 71 (8) ◽  
pp. 21-26
Author(s):  
Elena-Emilia Oprescu ◽  
Cristina-Emanuela Enascuta ◽  
Elena Radu ◽  
Vasile Lavric
Keyword(s):  
Maximum Yield ◽  
Strength Distribution ◽  
Point Of View ◽  
Reaction Parameters ◽  
X Ray ◽  
Ethyl Levulinate ◽  
Ft Ir ◽  
Ir Analysis ◽  
Biodiesel Blend ◽  
Acid Strength Distribution

In this study, the SO42-/TiO2-La2O3-Fe2O3 catalyst was prepared and tested in the conversion of fructose to ethyl levulinate . The catalyst was characterized from the point of view of the textural analysis, FT-IR analysis, acid strength distribution, X-ray powder diffraction and pyridine adsorption IR spectra. The influence of the reaction parameters on the ethyl levulinate yield was study. The maximum yield of 37.95% in levulinate esters was obtained at 180 �C, 2 g catalyst and 4 h reaction time. The effect of ethyl levulinate addition to diesel-biodiesel blend in different rates, i.e, 0.5, 1, 2.5, 5 (w.t %) on density, kinematic viscosity and flash point was evaluated and compared with the European specification.

Use of a sequencing batch biofilter for degradation of azo dyes (acids and bases)

2000 ◽  
Vol 42 (5-6) ◽  
pp. 329-336 ◽  
Author(s):  
M. Quezada ◽  
I. Linares ◽  
G. Buitrón
Keyword(s):  
Azo Dyes ◽  
Azo Dye ◽  
Degradation Rate ◽  
Removal Rate ◽  
Textile Effluent ◽  
Colour Removal ◽  
Substrate Degradation ◽  
Acids And Bases ◽  
Removal Efficiencies ◽  
Basic Red 46

The degradation of azo dyes in an aerobic biofilter operated in an SBR system was studied. The azo dyes studied were Acid Red 151 and a textile effluent containing basic dyes (Basic Blue 41, Basic Red 46 and 16 and Basic Yellow 28 and 19). In the case of Acid Red 151 a maximal substrate degradation rate of 288 mg AR 151/lliquid·d was obtained and degradation efficiencies were between 60 and 99%. Mineralization studies showed that 73% (as carbon) of the initial azo dye was transformed to CO2 by the consortia. The textile effluent was efficiently biodegraded by the reactor. A maximal removal rate of 2.3 kg COD/lliquid·d was obtained with removal efficiencies (as COD) varying from 76 to 97%. In all the cycles the system presented 80% of colour removal.

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