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Flocculation mechanism of modified bioflocculant for leather wastewater treatment / Zhang Yizhuo in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 104, N° 4 (07-08/2020)
[article]
Titre : Flocculation mechanism of modified bioflocculant for leather wastewater treatment Type de document : texte imprimé Auteurs : Zhang Yizhuo, Auteur ; Yang Qinhuan, Auteur ; Changqing Zhao, Auteur Année de publication : 2020 Article en page(s) : p. 184-190 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Biomatériaux
Cuirs et peaux -- Industrie -- Aspect de l'environnement
Eaux usées -- Epuration
Eaux usées -- Recyclage
FloculationIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : Leather processing produces a large amount of wastewater with complex components. In particular, wastewater denitrification is a worldwide environmental problem. In this experiment, according to the characteristics of high concentration of suspended solid and heavy pollution load in leather wastewater, Bacillus cereus was used as the microbiota producing flocculant and its metabolites were collected as bioflocculant. Ampholytic starch was a novel selection for chemical modification, and the modified bioflocculant was used to treat leather wastewater. After determination, the removal rate of total nitrogen reached 100%, and the flocculation efficiency reached 98.17%. Exploring the flocculation mechanism of the modified bioflocculant for treating leather wastewater, shows that the modified bioflocculant and the pollutants in the wastewater were bonded by ionic bonds, and the particle size of supernatant in leather wastewater system gradually decreased from 2026nm to 147nm when the added modified bioflocculant charge was 0.08g, which indicated the existence of adsorption and bridging. In addition, the change of peak on the infrared spectrogram of the flocculation sediment indicated the chemical interaction of the functional groups such as -OH, -COOH in the flocculation process. When the pH of flocculation system rose from 4.0 to 8.0, the potential rose from -36mV to 1 mV, which proved that a strong charge neutralisation occurred. Through observing the appearance of particles in leather wastewater system, it was found that multi-network overlapping structure flocs were formed after the modified bioflocculant interacted with wastewater, and the flocs could capture the remaining pollutants in wastewater, which proved that sweep-floc coagulation occurred. The results showed that the modified bioflocculant combined with a variety of flocculation ways in the treatment of leather wastewater which enhanced the flocculation ability. This study clarified the flocculation mechanism of modified bioflocculant and further, provided a reference for the development of new more efficient bioflocculant which is environment friendly. Note de contenu : - EXPERIMENTAL PROCEDURE : Materials - Collection of bioflocculant - Preparation of leather wastewater - Determination of the flocculation efficiency - Determination of the total nitrogen
- EXPLORATION OF FLOCCULATION MECHANISM : The exploration of adsorption and bridging - The exploration of chemical interaction - The exploration of charge neutralisation - The exploration of sweep-floc coagulation
- RESULTS AND DISCUSSION : Performance determination of modified bioflocculant treatment of leather wastewater
- THE FLOCCULATION MECHANISM IN THE TREATMENT OF LEATHER WASTEWATER : The exploration of the adsorption and bridging - The exploration of chemical interaction - The exploration of charge neutralisation - The exploration of sweep-floc coagulation - Application and analysis of the potential of the modified bioflocculantEn ligne : https://drive.google.com/file/d/1Fj4XBve2Zagf1G1jPqWG1-13qg5OpfWA/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=34331
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 104, N° 4 (07-08/2020) . - p. 184-190[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 21881 - Périodique Bibliothèque principale Documentaires Disponible Fumed metal oxide dispersions expand aqueous inkjet printing substrates / Tianqi Liu in COATINGS WORLD, Vol. 24, N° 3 (03/2019)
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Titre : Fumed metal oxide dispersions expand aqueous inkjet printing substrates Type de document : texte imprimé Auteurs : Tianqi Liu, Auteur ; Koen Burger, Auteur Année de publication : 2019 Langues : Américain (ame) Catégories : Alcool polyvinylique
Alumine
Couche de base
Dispersions et suspensions
Encre en phase aqueuse
Floculation
Impression jet d'encre
Liants
Matières plastiques -- Revêtement
Oxydes métalliques
Polyéthylène téréphtalate
Polyuréthanes
Potentiel zeta
Revêtements organiques
SiliceLa silice est la forme naturelle du dioxyde de silicium (SiO2) qui entre dans la composition de nombreux minéraux.
La silice existe à l'état libre sous différentes formes cristallines ou amorphes et à l'état combiné dans les silicates, les groupes SiO2 étant alors liés à d'autres atomes (Al : Aluminium, Fe : Fer, Mg : Magnésium, Ca : Calcium, Na : Sodium, K : Potassium...).
Les silicates sont les constituants principaux du manteau et de l'écorce terrestre. La silice libre est également très abondante dans la nature, sous forme de quartz, de calcédoine et de terre de diatomée. La silice représente 60,6 % de la masse de la croûte terrestre continentale.Index. décimale : 667.9 Revêtements et enduits Résumé : As aqueous inkjet continues to take market shares from traditional printing techniques, it must expand its substrates from traditional office paper to a broader spectrum of substrates used for packaging, signage and labels. CAB-O-SPERSE® silica and alumina dispersions can help prime difficult substrates to work with aqueous inkjet inks because of the porosity they generate and their surface charge characteristics. These dispersions enable the formulation of precoats that can greatly enhance optimized image quality such as high color saturation, less mottle and wet smudge resistance. They also offer stability and flexibility in the waterborne coating systems. Note de contenu : - Fumed metal oxide dispersions - key component in an aqueous inkjet receptive coating
- Dispersions offer stability and flexibility in waterborne coatings
- Fig. 1 : Examples of aqueous inkjet printing issues due to slow liquid removal from the printing surface
- Fig. 2 : Pore volume distribution in coatings made with fumed metal oxide dispersions
- Fig. 3 : Kyocera test bed printing at 250 feet/min of an aqueous inkjet ink sets on PET substrates. A: original PET film ; B : PET film precoated with PG003 dispersion and a polyurethane binder ; C : timed finger smear test on cyan color printed on the precoated PET
- Fig. 4 : Kyocera test bed printing at 250 feet/min of an aqueous inkjet ink set on a porous substrate. Three secondary colors (blue, red and green) and one composite black (cyan, magenta and yellow) are printed. A : original paper liner for corrugated board ; B : paper liner precoated with PG003 dispersion and a polyurethane binder
- Fig. 5 : Schematic illustration of an inkjet receptive coating made using a silica dispersion and a polymer binder
- Fig. 6 : Zeta potential curves for two representative silica dispersions
- Fig. 7 : Stability of a fumed silica dispersion (2020K) on the left vs a surface modified calcium carbonate dispersion (on the right) in the presence of a polyvinyl alcohol binder after overnight
- Fig. 8 : Photos of an image under films coated on PET. A : coating made using dispersion 4012K ; B : coating made using dispersion 1030K
- Fig. 9 : Flocculation in a cationic coating system with low charge density cationic silica and a cationic polymer latex
- Fig. 10 : Coating solution stability at t=1hr and t= 1 month when cationic silicas are mixed with a cationic charged polyurethane binder. Vial on the left : low charge density cationic silica; vial on the right : higher charge density cationic silicaEn ligne : https://www.coatingsworld.com/issues/2019-03-01/view_technical-papers/fumed-meta [...] Format de la ressource électronique : Html Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=32509
in COATINGS WORLD > Vol. 24, N° 3 (03/2019)[article]Investigation of effect of type of pigment/extender on the stability of high pigment volume concentration water-based architectural paint / Ritesh A. Bhavsar in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 19, N° 3 (05/2022)
[article]
Titre : Investigation of effect of type of pigment/extender on the stability of high pigment volume concentration water-based architectural paint Type de document : texte imprimé Auteurs : Ritesh A. Bhavsar, Auteur ; Avinash Sardesai, Auteur Année de publication : 2022 Article en page(s) : p. 919-930 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Caractérisation
Charges (matériaux)
Concentration pigmentaire volumique
Diluants
Dispersions et suspensions -- Stabilité
Floculation
Pigments inorganiques
Potentiel zeta
Revêtements en bâtiment:Peinture en bâtiment
Revêtements en phase aqueuse -- Additifs:Peinture en phase aqueuse -- Additifs
Revêtements organiquesIndex. décimale : 667.9 Revêtements et enduits Résumé : This article elucidates the effect of type of pigment/extenders viz. titanium dioxide (TiO2), magnesium silicate (steatite), calcium carbonate, dolomite, precipitated sodium magnesium aluminosilicates, hydrated and calcined aluminum silicates (kaolin) when used alone or in combination in the paint dispersions on their sedimentation stability. Accelerated heat age stability test was conducted as per ASTM D 1849. Wettability of pigment extenders were measured in terms of their contact angle using Washburn technique. Rheology viscosity curve and oscillatory amplitude sweep test are carried out to depict the structural properties, more precisely the extent of flocculation in the paint dispersion. From rheology viscosity curve, extent of residual flocculation is determined using Asbeck extrapolation method. Extent of total flocculation in the paint dispersion is estimated from cohesive energy density (Ec) using oscillatory amplitude sweep test. Energy of separation of particles in flocs (Esep) is also determined using yield point measurement. Attempt was made to correlate extent of flocculation present in paint dispersion with settling and syneresis observed during accelerated heat age stability test. It is observed that, the paint dispersions based on only TiO2, only hydrous kaolin and only precipitated sodium magnesium aluminosilicates are found to be quite stable whereas the dispersions based on only magnesium silicates and only calcined kaolin are found to be unstable. Paint dispersions based on carbonate extenders show syneresis and soft settling which is easily mixable. From the rheological study, it is identified that Ec is the most crucial parameter that correlates very well with the accelerated heat age stability test results of paint dispersion. Note de contenu : - EXTENT OF FLOCCULATION : Investigation of degree of residual flocculation using Asbeck extrapolation method - Energy of separation between the particles in a flocs (E sep) - Cohesive energy density (E c)
- EXPERIMENTAL WORK : Materials - Preparation of dispersion - Characterization
- RESULTS AND DISCUSSION : Effect of type of pigment/extenders on the stability of high PVC interior paint - Powder wettability - Rheological characterization - Effect of varying ratio of unstable to stable pigment and extenders on the stability of Paint-1
- Table 1 : Physico-chemical properties of pigments and extenders used in paint dispersion
- Table 2 : Key formulation ingredients of high PVC interior paint-1 and their respective experiments with individual pigment/extender at same volume solid content
- Table 3 : Summary of pH, zeta potential, stormer viscosity of paint dispersions before and after accelerated heat age stability test
- Table 4 : Material constant and powder contact angle with DI water and surfactant solution
- Table 5 : Infinite shear viscosity (η∞) and the extent of residual flocculation (m) as computed from Asbeck model, yield point (τ0) and energy of separation of particles in floccs (Esep), viscoelastic parameter G′ and critical strain (Υc) and cohesive energy density (Ec) is summarizedDOI : https://doi.org/10.1007/s11998-021-00568-9 En ligne : https://link.springer.com/content/pdf/10.1007/s11998-021-00568-9.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38086
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 19, N° 3 (05/2022) . - p. 919-930[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 23605 - Périodique Bibliothèque principale Documentaires Disponible Medium optimisation for bioflocculant produced from bacillus cereus / Changqing Zhao in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 101, N° 3 (05-06/2017)
[article]
Titre : Medium optimisation for bioflocculant produced from bacillus cereus Type de document : texte imprimé Auteurs : Changqing Zhao, Auteur ; Che Chun, Auteur ; Yang Qinhuan, Auteur Année de publication : 2017 Article en page(s) : p. 129-134 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Biomatériaux
Eaux usées -- Epuration
Floculant
Floculation
SelsIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : This paper further investigated a previous study that discovered a strain of Bacillus camus with a flocculation effect. Based on the initial medium, single-factor experiments were carried out to optimise the carbon and nitrogen sources and their concentrations. Inorganic salts with differing concentrations were successively tested through single factor, orthogonal, and composite experiments, from which an optimal medium recipe was determined with the highest flocculation activity. Next, the flocculation activity and yield of the bioflocculant were compared between the optimal medium and the initial medium. The results showed that 40g/L mannitol was the optimal carbon source, and 4g/1._ peptone was the optimal nitrogen source, white 0.75g/L l<21-1PO4 was the highest amongst the inorganic salts. Considering the carbon sources, nitrogen sources, and inorganic salts, the optimal medium with the highest flocculation activity was 40g/L mannitol, 4g/L peptone, and 0.75g/L K2HPO4. It was found that the optimal medium increased the yiefd of the bioflocculant produced by Bacillus cereus by 189.70% and the flocculation activity by 58.87%, which was a significant improvement. These experimental results are of great importance in increasing the efficiency of wastewater treatment and reducing the cost of bioflocculant. Note de contenu : - MATERIALS AND METHODS : Experimental strains and media - Strain inoculation - Determination of flocculation - Single factor optimisation of carbon source - Single factor optimisation of the nitrogen source - Optimisation of inorganic salts - Comparison of the effects of the optimised and the initial medium
- RESULTS AND DISCUSSION : Optimisation of carbon source - Optimisation of nitrogen source - Optimisation of inorganic salts - Comparison of the effects of the initial medium and the optimised mediumEn ligne : https://drive.google.com/file/d/1IYo2vy4BMYcJJGVtu2m_ZLhW1jwDa0yH/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=28797
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 101, N° 3 (05-06/2017) . - p. 129-134[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 19049 - Périodique Bibliothèque principale Documentaires Disponible Modélisation structurelle du comportement rhéo-épaississant des fluides complexes. Application aux dispersions colloïdales / D. Quemada in LES CAHIERS DE RHEOLOGIE, Vol. XIV, N° 1 (09/1995)
[article]
Titre : Modélisation structurelle du comportement rhéo-épaississant des fluides complexes. Application aux dispersions colloïdales Type de document : texte imprimé Auteurs : D. Quemada, Auteur Année de publication : 1995 Article en page(s) : p. 1-10 Note générale : Bibliogr. Langues : Français (fre) Catégories : Colloides
Dilatance
Dispersions et suspensions
Floculation
Fluides complexes
RhéologieIndex. décimale : 532.05 Mécanique des fluides et des liquides - Dynamique (cinétique et cinématique) Résumé : La modélisation rhéologique (stationnaire ou instationnaire) des fluides complexes (considérés comme des dispersions concentrées d'éléments plus ou moins structurés, appelés ici structurelles, US), utilise le concept de fraction volumique effective, elle même fonction (i) des interactions inter- et intra-US, (ii) des conditions d'écoulement, les forces hydrodynamiques pouvant modifier non seulement la fraction S de particules composant les US, mais aussi les arrangements formés par ces US ainsi que leur structure interne (notamment, leur compacité). La modélisation structurelle du rhéo-épaississement est développée dans ce cadre, qui conduit à une dépendance. Une équation cinétique gouverne la variable structurelle S.
Deux modèles dilatants- décrivant des suspensions de particules, soit interactives, soit sans interaction- sont discutés. Dans le premier (modèle structurel "à floculation induite"), la croissance de n(y) résulte d'une cinétique où entrent en compétition un terme de rupture des amas (dominant à faible y), et un terme de floculation sous cisaillement (mais limité par une probabilité de collage, dominant à fort y). Le second, (modèle structurel "à compacité variable"), suppose qu'à partir d'un certain y critique, les US de compacité maximum se transforment progressivement en US de plus faible compacité, chacune des deux populations étant gouvernée par sa propre cinétique. Ce dernier modèle semble intéressant parce qu'il prédit les discontinuités de la viscosité ainsi que les variations des cisaillements critiques avec la fraction volumique, observées dans un grand nombre de dispersions.Note de contenu : - Le modèle structurel
- Modèle structurel "à floculation induite" (modèle SFI)
- Modèle structurel "à compacité variable" (modèle SCV)Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=26200
in LES CAHIERS DE RHEOLOGIE > Vol. XIV, N° 1 (09/1995) . - p. 1-10[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 002115 - Périodique Bibliothèque principale Documentaires Disponible Pigment dispersion : I / Zeno W. Wicks in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 73, N° 921 (10/2001)
PermalinkPermalinkLe réarrangement, un modèle permettant d'expliquer les différences de compacité et des propriétés rhéométriques des suspensions floculées / S. Ducerf in LES CAHIERS DE RHEOLOGIE, Vol. XIV, N° 1 (09/1995)
PermalinkStabilization of colloidal dispersions by polymer adsorption / Tatsuo Sato / New York [United States] : Marcel Dekker, Inc. (1980)
PermalinkSyneresis and rheology mechanisms of a latex-HEUR associative thickener system / Franceska A. Santos in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 14, N° 1 (01/2017)
PermalinkSynthesis and application of the cationic lignin amine flocculant / Y. Jiao in TENSIDE, SURFACTANTS, DETERGENTS, Vol. 47, N° 6/2010 (11-12/2010)
PermalinkSynthesis and evaluation of a novel shavings-based cationic flocculant / Dai Chunji in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 102, N° 2 (03-04/2018)
PermalinkTannery wastewater treatment : conventional and promising processes, an updated 20-year review / Jun Zhao in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)
PermalinkVariables influencing microflocculation in coalesced emulsion in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 73, N° 916 (05/2001)
PermalinkVers le rejet zéro : étude technico-économique / Bertrand Sancey in GALVANO ORGANO, N° 832 (10/2014)
PermalinkWavelength dependence of Kubelka–Munk scattering spectra for studies of TiO2 microstructure and aggregation in paints / Nick J. Elton in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 11, N° 4 (07/2014)
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