scholarly journals Chemical Characterization of Specific Micropollutants from Textile Industry Effluents in Fez City, Morocco

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Hakima Talouizte ◽  
Mohammed Merzouki ◽  
Mohammed Benlemlih ◽  
Mohammed Bendriss Amraoui

Textile industry is one of the most polluting industries in the world. It has a high importance in terms of its environment impact, since it consumes a considerably large amount of water and produces highly polluted discharge water. In this work, characterization of toxic organic compounds is proposed. Based on gas chromatography coupled to mass spectrometry (GC/MS) screening analysis, organic micropollutant diversity of textile effluents from a local textile processing factory was investigated. In the present work, physicochemical characterization of the studied textile effluents showed considerably high values of principal pollution parameters above the prescribed discharge water limits. Heavy metals like zinc (Zn), copper (Cu), iron (Fe), nickel (Ni), cadmium (Cd), chromium (Cr), and lead (Pb) were found to be present within the permissible limits. The results of GC/MS revealed the presence of various organic compounds belonging to a wide range of chemical classes. Main groups of chemical compounds detected in these effluents were aromatic carboxylic acids, alkanes, aromatic amines, phthalates, aliphatic carboxylic acids, and linear aliphatic alcohols. The results of this study allowed significant contributions to the chemical characterization of textile industry contaminants and identification of indicators that can be considered an important tool for assessment of the potential impact of textile activities to the contamination of aquatic environment and health hazard.

2012 ◽  
Vol 46 (19) ◽  
pp. 10455-10462 ◽  
Author(s):  
Manuela van Pinxteren ◽  
Conny Müller ◽  
Yoshiteru Iinuma ◽  
Christian Stolle ◽  
Hartmut Herrmann

Author(s):  
Nguyen Hong Nam ◽  
Le Gia Thanh Truc ◽  
Khuong Duy Anh ◽  
Laurent Van De Steene

Agricultural and forest residues are potential sources of renewable energy in various countries. However, the difference in characteristics of biomass resources presents challenges for energy conversion processes which often require feedstocks that are physically and chemically consistent. This study presented a complete and comprehensive database of characteristics of a wide range of agricultural and forest residues. Moisture, bulk density, calorific value, proximate and elemental compositions, as well as cellulose, hemicellulose, and lignin compositions of a wide range of biomass residues were analyzed. The major impacts of the variability in biomass compositions to biochemical and thermochemical processes were also discussed.


2013 ◽  
Vol 67 (12) ◽  
pp. 2791-2799 ◽  
Author(s):  
Y. Mountassir ◽  
A. Benyaich ◽  
M. Rezrazi ◽  
P. Berçot ◽  
L. Gebrati

The objectives of this work were to carry out a complete characterization of textile wastewater, resulting from a textile unit located in the Marrakesh region. A physico-chemical characterization has been performed, focused on organic and toxicological aspects. The cladoceran Daphnia magna was used as the sensor organism and lethal concentration as a criterion to measure the toxicity of textile wastewater. The physico-chemical and toxicological status of a local textile effluent showed considerable values limitation, when compared to the European Union standard limit and Moroccan guide level and other studies. In view of those characteristics, the wastewater effluent from the textile industry should be considered to be treated before discharge to the environment.


2003 ◽  
Vol 18 (10) ◽  
pp. 2522-2527 ◽  
Author(s):  
E. D. Specht ◽  
A. Rar ◽  
G. M. Pharr ◽  
E. P. George ◽  
P. Zschack ◽  
...  

A technique based on synchrotron radiation was developed that allows for rapid structural and chemical characterization of ternary alloys over a wide range of composition. The technique was applied to isothermal sections of the Cr–Fe–Ni system grown on Al2O3(0001) sapphire substrates by sequential deposition of layers of graded.thickness followed by annealing to interdiffuse the elements. A film spanning the Cr–Fe–Ni ternary system was measured in 4 h at a resolution of 2 at.% by rastering the sample under a focused beam of synchrotron radiation while simultaneously measuring the diffraction pattern with a charge-coupled device detector to determine crystallographic phases, texture, and lattice parameters and also measuring the x-ray fluorescence with an energy-dispersive detector to determine elemental composition. Maps of phase composition and lattice parameter as a function of composition for several annealing treatments were found to be consistent with equilibrium values. The technique will be useful in combinatorial materials design.


2019 ◽  
Vol 12 (6) ◽  
pp. 3137-3149 ◽  
Author(s):  
Xiaoxi Liu ◽  
Benjamin Deming ◽  
Demetrios Pagonis ◽  
Douglas A. Day ◽  
Brett B. Palm ◽  
...  

Abstract. Recent work has quantified the delay times in measurements of volatile organic compounds (VOCs) caused by the partitioning between the gas phase and the surfaces of the inlet tubing and instrument itself. In this study we quantify wall partitioning effects on time responses and transmission of multifunctional, semivolatile, and intermediate-volatility organic compounds (S/IVOCs) with saturation concentrations (C∗) between 100 and 104 µg m−3. The instrument delays of several chemical ionization mass spectrometer (CIMS) instruments increase with decreasing C∗, ranging from seconds to tens of minutes, except for the NO3- CIMS where it is always on the order of seconds. Six different tubing materials were tested. Teflon, including PFA, FEP, and conductive PFA, performs better than metals and Nafion in terms of both delay time and transmission efficiency. Analogous to instrument responses, tubing delays increase as C∗ decreases, from less than a minute to >100 min. The delays caused by Teflon tubing vs. C∗ can be modeled using the simple chromatography model of Pagonis et al. (2017). The model can be used to estimate the equivalent absorbing mass concentration (Cw) of each material, and to estimate delays under different flow rates and tubing dimensions. We also include time delay measurements from a series of small polar organic and inorganic analytes in PFA tubing measured by CIMS. Small polar molecules behave differently than larger organic ones, with their delays being predicted by their Henry's law constants instead of their C∗, suggesting the dominance of partitioning to small amounts of water on sampling surfaces as a result of their polarity and acidity properties. PFA tubing has the best performance for gas-only sampling, while conductive PFA appears very promising for sampling S/IVOCs and particles simultaneously. The observed delays and low transmission both affect the quality of gas quantification, especially when no direct calibration is available. Improvements in sampling and instrument response are needed for fast atmospheric measurements of a wide range of S/IVOCs (e.g., by aircraft or for eddy covariance). These methods and results are also useful for more general characterization of surface–gas interactions.


2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Dharani Das ◽  
Yong Yang ◽  
Julie S. O’Brien ◽  
Dalibor Breznan ◽  
Surendra Nimesh ◽  
...  

There exists a knowledge gap in understanding potential toxicity of mesoporous silica nanoparticles. A critical step in assessing toxicity of these particles is to have a wide size range with different chemistries and physicochemical properties. There are several challenges when synthesizing mesoporous silica nanoparticles over a wide range of sizes including (1) nonuniform synthesis protocols using the same starting materials, (2) the low material yield in a single batch synthesis (especially for particles below 60–70 nm), and (3) morphological instability during surfactant removal process and surface modifications. In this study, we synthesized a library of mesoporous silica nanoparticles with approximate particle sizes of 25, 70, 100, 170, and 600 nm. Surfaces of the silica nanoparticles were modified with hydrophilic-CH2–(CH2)2–COOH and relatively hydrophobic-CH2–(CH2)10–COOH functional groups. All silica nanoparticles were analysed for morphology, surface functionality, surface area/pore volume, surface organic content, and dispersion characteristics in liquid media. Our analysis revealed the synthesis of a spectrum of monodisperse bare and surface modified mesoporous silica nanoparticles with a narrow particle size distribution and devoid of cocontaminants critical for toxicity studies. Complete physicochemical characterization of these synthetic mesoporous silica nanoparticles will permit systematic toxicology studies for investigation of structure-activity relationships.


1994 ◽  
Vol 72 (3) ◽  
pp. 928-935 ◽  
Author(s):  
Paul G. Mezey

A density domain (DD) is the formal body enclosed by a molecular isodensity contour (MIDCO) surface. Individual nuclear neighborhoods and various formal molecular fragments can be regarded as fuzzy moieties of electron densities, dominated by one or several nuclei. Such a fuzzy fragment involves a whole range of density values, hence it cannot be described by a single MIDCO, but it can be represented by a sequence of density domains. Within the chemically important range of density values, there are only a finite number of topologically different bodies of density domains. In the Density Domain Approach, chemical bonding is described by the interfacing and mutual interpenetration of local fuzzy charge density clouds. The bonding between fragments of a molecule is characterized by a finite sequence of density domains within a wide range of density values and by the correponding sequence of topological patterns of the mutual interpenetration of these fragments. In earlier works, the DD approach was advocated as an alternative to the conventional "skeletal model" of chemical bonding. The classically motivated line diagrams as representatives of bonding are replaced by the pattern of interpenetration of fuzzy fragment bodies at various density thresholds. In this study, novel DD relations are described, suitable for a quantum chemical characterization of functional groups, the local shape properties of such groups, and their contributions to global molecular shape.


2019 ◽  
Author(s):  
Xiaoxi Liu ◽  
Benjamin Deming ◽  
Demetrios Pagonis ◽  
Douglas A. Day ◽  
Brett B. Palm ◽  
...  

Abstract. Recent work has quantified the delay times in measurements of volatile organic compounds (VOCs) caused by the partitioning between the gas phase and the surfaces of the inlet tubing and instrument itself. In this study we quantify wall partitioning effects on time responses and transmission of multi-functional, semivolatile and intermediate-volatility organic compounds (S/IVOCs) with saturation concentrations (C*) between 100 and 104 µg m−3. The instrument delays of several chemical ionization mass spectrometer (CIMS) instruments increase with decreasing C*, ranging from seconds to tens of minutes, except for the NO3−-CIMS where it is always on the order of seconds. Six different tubing materials were tested. Teflon, including PFA, FEP, and conductive PFA, performs better than metals and Nafion in terms of both delay time and transmission efficiency. Analogous to instrument responses, tubing delays increase as C* decreases, from less than a minute to > 100 min. The delays caused by Teflon tubing vs. C* can be modeled using the simple chromatography model of Pagonis et al. (2017). The model can be used to estimate the equivalent absorbing mass concentration (Cw) of each material, and to estimate delays under different flow rates and tubing dimensions. We also include time delay measurements from a series of small polar organic and inorganic analytes in PFA tubing measured by CIMS. Small polar molecules behave differently than larger organic ones, with their delays being predicted by their Henry’s law constants instead of their C*, suggesting the dominance of partitioning to small amounts of water on sampling surfaces as a result of their polarity and acidity properties. PFA tubing has the best performance for gas-only sampling, while conductive PFA appears very promising for sampling S/IVOCs and particles simultaneously. The observed delays and low transmission both affect the quality of gas quantification, especially when no direct calibration is available. Improvements in sampling and instrument response are needed for fast atmospheric measurements of a wide range of S/IVOCs (e.g., by aircraft or for eddy covariance). These methods and results are also useful for more general characterization of surface/gas interactions.


2015 ◽  
Vol 05 (05) ◽  
pp. 317-324 ◽  
Author(s):  
Farjana Ahmed ◽  
Abdul Alim ◽  
Fahmida Alam ◽  
Tahsina Islam ◽  
Ali Azam Talukder

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