Preparation of Organovermiculite for Adsorption of Organic Compounds

2012 ◽  
Vol 727-728 ◽  
pp. 1451-1456
Author(s):  
Andréa Lopes Silva ◽  
Francisco Kegenaldo Alves de Souza ◽  
Gelmires Araújo Neves ◽  
Romualdo Rodrigues Menezes ◽  
Hélio Lucena Lira ◽  
...  
Keyword(s):  
Organic Compounds ◽  
Organic Pollutants ◽  
Organic Contaminants ◽  
Exchange Capacity ◽  
Natural Clay ◽  
Modified Clay ◽  
Organically Modified ◽  
Dimethyl Ammonium ◽  
Cationic Exchange ◽  
Clay Materials

Organically modified clay minerals are widely used as sorbents for hydrophobic organic compounds e.g., organic pollutants treatment from water solutions. Natural clay materials are hydrophilic and therefore they are not efficient sorbents for organic compounds. Intercalations of natural clay materials, with organic cations, with quaternary ammonium groups may become these clays hydrophobic. Vermiculite is the mineralogical name given to hydrated laminar magnesium-aluminum-iron silicate; this natural clay was modified and used for the production of organically modified clay (organovermiculite), with the purpose of its use in removing organic contaminants. The organovermiculite was prepared using different concentrations of distearyl dimethyl ammonium chloride (praepagen) based on cationic exchange capacity of the clay. It was evident from the X-ray diffraction that the salt was incorporated to the clay structure confirming its organophilization and through the Foster swelling test it was observed the affinity between the organic pollutants and the organovermiculite.

Passive sampling as a tool for determination of micro-organic compounds in groundwater resources

2020 ◽  
Author(s):  
Nina Mali ◽  
Anja Koroša ◽  
Primož Auersperger
Keyword(s):  
Organic Compounds ◽  
Organic Pollutants ◽  
Organic Contaminants ◽  
Passive Sampling ◽  
Groundwater Resources ◽  
Sampling Technique ◽  
Sampling Period ◽  
Gas Chromatography Mass Spectrometry ◽  
Grab Sampling

<p>Micro-organic (MO) compounds have been recognized as an important factor in environmental pollution. Developments in a range of analytical techniques are expanding the number of MOs that can be detected in groundwater. They may not be new contaminants, but recently detected using improved sampling and analytical methods. Monitoring programmes for groundwater are largely based on the collection of grab (spot) samples. One of the methods to determine the presence of organic compounds in groundwater v can also be passive sampling. Contrary to grab sampling, passive sampling is less sensitive to accidental extreme variations of the organic compounds concentrations in groundwater and it also allows determination of a large range of contaminants at once. A passive sampler can cover a long sampling period, integrating the pollutant concentration over time. This paper presents the application of the passive sampling technique for monitoring organic pollutants within the four major alluvial aquifers in Slovenia used for water supply. Passive samples were analyzed by gas chromatography mass spectrometry (GC-MS). For the interpretation of chromatograms, the AMDIS deconvolution was used. The deconvolution was covered by the GC-MS library with retention times for 921 organic contaminants from Agilent USA, as well as by the NIST 2008 library of mass spectra. Most frequently detected MO substances were classified in different pollutant groups with respect to their origin (urban source, agriculture or industry). Based on the results, a comparison of the presence of MOs in the present aquifers was made. Passive sampling with active carbon fibres was proved to be an appropriate method for monitoring micro-organic pollutants in groundwater.</p>

scholarly journals Adsorption Behavior of Cationic Dye on Bentonite Functionalized With 3-aminopropyltriethoxysilane

2021 ◽  
Author(s):  
MAZOURI BELHADRI ◽  
Adel Mokhtar ◽  
Abdelkader Bengueddach Bengueddach ◽  
mohamed sassi
Keyword(s):  
Bentonite Clay ◽  
Exchange Capacity ◽  
Blue Dye ◽  
Adsorption Model ◽  
X Ray Diffraction ◽  
Adsorption Parameters ◽  
Modified Clay ◽  
Pseudo Second Order ◽  
Cationic Exchange ◽  
Hydrolysis Of

Abstract The current study focused on the modification of Algerian bentonite clay (Bent) with the product of hydrolysis of 3-aminopropyltriethoxysilane (APTES) using the intercalation process. The modified clay (Bent-APTES) was investigated as an adsorbent solid for methylene blue dye (MB) removal from wastewater.The Bent-APTES was characterized by X-ray diffraction (XRD), chemical analyses, Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The cationic exchange capacity was also determined. Several adsorption parameters were evaluated on the adsorption performance. The results showed that the equilibrium adsorption data was found to fit better to the Langmuir adsorption model, and the adsorption capacity for the removal of MB on Bent-APTES was 217.39 mg g-1. The kinetic process of adsorption could be described by the pseudo-second order model. Consequently, the modified clay could be served as an efficient adsorbent for cationic dyes in wastewater treatment.

Microbiological Detoxification of Hazardous Organic Contaminants: The Crucial Role of Substrate Interactions

1992 ◽  
Vol 25 (11) ◽  
pp. 403-410 ◽  
Author(s):  
B. E. Rittmann
Keyword(s):  
Organic Pollutants ◽  
Information Flow ◽  
Organic Contaminants ◽  
Crucial Role ◽  
Substrate Utilization ◽  
Energy Flows ◽  
Hazardous Pollutants ◽  
Primary Substrate ◽  
Substrate Types

Microbiological detoxification of hazardous organic pollutants is highly promising, but its reliable implementation requires a sophisticated understanding of several different substrate types and how they interact. This paper carefully defines the substrate types and explains how their interactions affect the bacteria's electron and energy flows, information flow, and degradative activity. For example, primary substrates, which are essential for growth and maintenance of the bacteria, also interact with degradation of specific hazardous pollutants by being inducers, inhibitors, and direct or indirect cosubstrates. The target contaminants, which often are secondary substrates, also have the interactive roles of self-inhibitor, inhibitor of primary-substrate utilization, inducer, and a part of an aggregate primary substrate.

scholarly journals Multi-Oxygenated Organic Compounds in Fine Particulate Matter Collected in the Western Mediterranean Area

Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 94
Author(s):  
Esther Borrás ◽  
Luis Antonio Tortajada-Genaro ◽  
Francisco Sanz ◽  
Amalia Muñoz
Keyword(s):  
Particulate Matter ◽  
Carboxylic Acids ◽  
Organic Compounds ◽  
Organic Pollutants ◽  
Mediterranean Area ◽  
Western Mediterranean ◽  
Anthropogenic Sources ◽  
Gas Chromatography Mass Spectrometry ◽  
Industrial Emissions ◽  
Tetradecanoic Acid

The chemical characterization of aerosols, especially fine organic fraction, is a relevant atmospheric challenge because their composition highly depends on localization. Herein, we studied the concentration of multi-oxygenated organic compounds in the western Mediterranean area, focusing on sources and the effect of air patterns. The organic aerosol fraction ranged 3–22% of the total organic mass in particulate matter (PM)2.5. Seventy multi-oxygenated organic pollutants were identified by gas chromatography–mass spectrometry, including n-alkanones, n-alcohols, anhydrosugars, monocarboxylic acids, dicarboxylic acids, and keto-derivatives. The highest concentrations were found for carboxylic acids, such as linoleic acid, tetradecanoic acid and, palmitic acid. Biomarkers for vegetation sources, such as levoglucosan and some fatty acids were detected at most locations. In addition, carboxylic acids from anthropogenic sources—mainly traffic and cooking—have been identified. The results indicate that the organic PM fraction in this region is formed mainly from biogenic pollutants, emitted directly by vegetation, and from the degradation products of anthropogenic and biogenic volatile organic pollutants. Moreover, the chemical profile suggested that this area is interesting for aerosol studies because several processes such as local costal breezes, industrial emissions, and desert intrusions affect fine PM composition.

Asymmetric mixed matrix membrane incorporating organically modified clay particle for gas separation

2014 ◽  
Vol 241 ◽  
pp. 495-503 ◽  
Author(s):  
A.K. Zulhairun ◽  
A.F. Ismail ◽  
T. Matsuura ◽  
M.S. Abdullah ◽  
A. Mustafa
Keyword(s):  
Gas Separation ◽  
Clay Particle ◽  
Mixed Matrix Membrane ◽  
Mixed Matrix ◽  
Modified Clay ◽  
Organically Modified

Use of polysaccharide based surfactants to stabilize organically modified clay particles aqueous dispersion

2013 ◽  
Vol 94 (1) ◽  
pp. 687-694 ◽  
Author(s):  
Manja Kurečič ◽  
Majda Sfiligoj Smole ◽  
Karin Stana-Kleinschek
Keyword(s):  
Aqueous Dispersion ◽  
Clay Particles ◽  
Modified Clay ◽  
Organically Modified

Bio-based Polyurethane-clay Nanocomposite Foams: Systheses and Properties

2009 ◽  
Vol 1188 ◽  
Author(s):  
Min Liu ◽  
Zoran S. Petrovic ◽  
Yijin Xu
Keyword(s):  
Thermal Conductivity ◽  
Thermal Insulation ◽  
Cell Structure ◽  
Polyurethane Foams ◽  
Mechanical And Thermal Properties ◽  
Cell Content ◽  
Modified Clay ◽  
Rigid Polyurethane Foams ◽  
Nanocomposite Foams ◽  
Organically Modified

AbstractStarting from a bio-based polyol through modification of soybean oil, BIOH™ X-210, two series of bio-based polyurethanes-clay nanocomposite foams have been prepared. The effects of organically-modified clay types and loadings on foam morphology, cell structure, and the mechanical and thermal properties of these bio-based polyurethanes-clay nanocomposite foams have been studied with optical microscopy, compression test, thermal conductivity, DMA and TGA characterization. Density of nanocomposite foams decreases with the increase of clay loadings, while reduced 10% compressive stress and yield stress keep constant up to 2.5% clay loading in polyol. The friability of rigid polyurethane-clay nanocomposite foams is high than that of foam without clay, and the friability for nanofoams from Cloisite® 10A is higher than that from 30B at the same clay loadings. The incorporation of clay nanoplatelets decreases the cell size in nanocomposite foams, meanwhile increases the cell density; which would be helpful in terms of improving thermal insulation properties. All the nanocomposite foams were characterized by increased closed cell content compared with the control foam from X-210 without clay, suggesting the potential to improve thermal insulation of rigid polyurethane foams by utilizing organically modified clay. Incorporation of clay into rigid polyurethane foams results in the increase in glass transition temperature: the Tg increased from 186 to 197 to 204 °C when 30B concentration in X-210 increased from 0 to 0.5 to 2.5%, respectively. Even though the thermal conductivity of nanocomposite foams from 30B is lower than or equal to that of rigid polyurethane control foam from X-210, thermal conductivity of nanocomposite foams from 10A is higher than that of control at all 10A concentrations. The reason for this abnormal phenomenon is not clear at this moment; investigation on this is on progress.

scholarly journals Intercalation of oxalate ions in the interlayer space of a layered double hydroxide for nickel ions adsorption

2016 ◽  
Vol 5 (2) ◽  
pp. 144
Author(s):  
Doungmo Giscard ◽  
Théophile Kamgaing ◽  
Ranil Clément Tonleu Temgoua ◽  
Ervice Ymele ◽  
Francis Merlin Melataguia Tchieno ◽  
...  
Keyword(s):  
Interlayer Space ◽  
X Ray Diffraction ◽  
Batch Mode ◽  
Nickel Ions ◽  
X Ray ◽  
Modified Clay ◽  
Pseudo Second Order ◽  
Oxalate Ions ◽  
Double Hydroxide ◽  
Clay Materials

In this study, sorption properties of a synthesized anionic clay were enhanced by the intercalation of oxalate ions in its interlayer space. The pristine and modified clay materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and thermal analysis. These techniques confirmed the presence of oxalate ions in the interlayer space of the clay. The intercalated clay was then used as a matrix for the sorption in batch mode of nickel ions in aqueous solution. The influence of a number of parameters such as contact time, pH, initial concentration of the analyte and adsorbent dosage were studied. The maximum adsorption of nickel was obtained at pH 6, that is, about 90% Ni2+ removal. The adsorbent/adsorbate equilibrium follows a pseudo-second order kinetics and best matches the Langmuir model. The modified clay was shown to be efficient matrix for the sorption of nickel ions.

Synthesis and Characterization of Silver-Histidine Complex Doped Montmorillonite Antibacterial Agent

2012 ◽  
Vol 510 ◽  
pp. 757-761 ◽  
Author(s):  
Shu’e Duan ◽  
Yun Hui Zhai ◽  
Ying Juan Qu
Keyword(s):  
Antibacterial Agent ◽  
Sea Water ◽  
Antibacterial Activities ◽  
Exchange Capacity ◽  
Salt Tolerant ◽  
X Ray Diffraction ◽  
Ion Exchange Reaction ◽  
Cationic Exchange ◽  
Loading Amount

In this paper a novel colorless and salt-tolerant silver-histidine complex doped montmorillonite (Na-MMT) antibacterial agent (SHMMT) power was synthesized by ion exchange reaction using silver-histidine complex ion [Ag (his)] + as precursor, and characterized by atomic absorption spectrophotometer (AAS) and power X-ray diffraction (XRD). The antibacterial activities against Pseudoalteromonas carrageenovora were examined by a modified broth dilution test and the plate counting method. The salt-tolerant property was determined by the antibacterial activities of the sea water soaked SHMMT. The results showed that the Ag loading amount of SHMMT powder reached 1.7mmol/g, far more than the cationic exchange capacity (CEC) of Na-MMT. SHMMT powder had high bacterial activity eventhough it was soaked in the sea water for 30 days. 1

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