Colloid electrohydrodynamics

This brief extracted review presents the recent development in basic and applied science and engineering of finely dispersed particles and related systems in general, but more profound and in-depth treatise are related to the liquid-liquid finely dispersed systems, i.e. emulsions and double emulsions. Twenty-five years ago, the idea, at first very fogy, came out from the pilot plant experiments related to the extraction Of uranium from wet phosphoric acid. In particular the solution of the entrainment problems, breaking of emulsions/double emulsions, as the succession of the extraction and stripping operations/processes, was performed In this pilot plant, secondary liquid-liquid phase separation loop was designed and carried out. The loop consisted of a lamellar coalescer and four flotation cells in series. Central equipment in the loop, relevant to this investigation, was the lamellar coalescer. The phase separation in this equipment is based on the action of external forces of mechanical and/or electrical origin, while adhesive processes at the inclined filling plates occur. Since many of related processes, e.g. adhesive processes, rupture processes and coalescence, were not very well understood, deeper research of these events and phenomena was a real scientific challenge

Electrochemical synthesis and characterization of basic bismuth nitrate [Bi6O5(OH)3](NO3)5·2H2O: a potential highly efficient sorbent for textile reactive dye removal

A new method of synthesis was developed for the preparation of basic bismuth nitrate [Bi6O5(OH)3](NO3)5·2H2O (ECBBN). Electrochemical synthesis of the material was carried out by galvanostatic electrodeposition from an acidic Bi(III) solution on a Ti substrate and further thermal treatment in air at 200 °C. Characterization of ECBBN was conducted by employing SEM–EDX, N2 adsorption, XRD and FTIR, and its pI was also determined. The analyses showed that the material obtained was pure [Bi6O5(OH)3](NO3)5·2H2O. Morphologically, ECBBN aggregates were composed of crystals, some smaller than 50 nm. Electrochemically synthesized sorbent (ECBBN) was used for the removal of the textile dye Reactive Blue 19 (RB19) from deionized water and model solutions of polluted river water, and it showed considerably superior sorption performance compared to other inorganic sorbents synthesized by conventional methods reported in the literature. A kinetic study suggests that the sorption process is both under reaction and diffusion control. Equilibration of the sorption process was attained in several minutes, i.e. the sorption process is very fast. The sorption equilibrium data were well interpreted by the Langmuir, Redlich–Peterson and Brouers–Sotolongo isotherm. Using Langmuir isotherm, the maximum sorption capacity of ECBBN was reached at pH 2 and was 1049.19 mg g−1

Synthesis and characterization of new Ti–Bi2O3 anode and its use for reactive dye degradation

This paper reports the synthesis, characterization and application of a Ti–Bi2O3 anode for the electrochemical decolorization of the textile dye Reactive Red 2. The anode was synthesized by electrodeposition on a Ti substrate immersed in an acidic bismuth (III) solution at constant potential, followed by calcination in air at 600 °C. Thermogravimetric Analysis (TGA), Energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) analysis revealed that the electrodeposited material was predominantly metallic bismuth, which was oxidized to pure α-Bi2O3 during the calcination in air. SEM micrographs revealed that the Bi2O3 coat at the anode surface was inhomogeneous and porous. Reactive Red 2 was completely electrochemically decolorized at the synthesized anode in the presence of H2O2. The applied current density, H2O2 and Na2SO4 concentration, medium pH and initial dye concentration affected the dye decolorization rate. The optimal process parameters were found to be as follows: an applied current density of 40 mA cm−2 using a mixture of 10 mmol dm−3 H2O2 and 10 mmol dm−3 Na2SO4 at pH 7. The dye decolorization rate was shown to decrease as its initial concentration increased. The decolorization reactions were found to follow pseudo-first order kinetics

Fifth European Dirofilaria and Angiostrongylus Days (FiEDAD) 2016

Peer reviewe

Electron and momentum transfer phenomena at developed deformable and rigid liquid-liquid interfaces

Primenjena je nova ideja za rasvetljavanje fenomena prenosa elektrona i količine kretanja na razvijenim, deformabilnim i rigidnim, međupovršinama u finim (mikro, nano, ato) disperznim sistemima. Ponašanje elektroviskoelastičnih fluida, na primer međupovršina tečno-tečno (emulzije dvostruke emulzije) se predstavlja u tri stanja/"nestabilnosti", rigidno elastično i plastično. Relevantni događaji na međupovršinama se posmatraju kao interakcije unutrašnjih (imanentnih) i spoljašnjih (incidentnih) periodičnih fizičkih polja. Pored fenomena prenosa količine kretanja toplote i mase, koji se koriste u hemijskom inženjerstvu, za posmatranja na nivou molekula, atoma i/ili entiteta neophodno je uvesti i fenomen prenosa elektrona. Za postulirani fizički formalizam, teoriju elektroviskoelastičnosti, izvedena su tri matematička formalizma. U prvom modelu posmatra se delovanje normalnih i tangencijalnih sila, samo u matematičkom smislu, bez obzira na njihovo poreklo (mehaničko i/ili električno). Drugi model je integro-diferencijalna jednačina tipa van der Pol. Treći model predstavlja generalizaciju modela van der Pol za oba slučaja, linearni i nelinearni, integrali i diferencijali reda celih brojeva su zamenjeni integralima i diferencijalima reda izlomljenih brojeva. Predstavljeni modeli i teorija omogućavaju dublje razumevanje: problema zahvatanja u ekstrakciji tečno-tečno, događaja na razvijenim međupovršinama u nauci o koloidima i međupovršinama, hemijskih i biohemijskih senzora elektroanalitičkih metoda, biologije/biomedicine (hematiologije, genetike elektroneurofiziologije).A new idea was applied for the elucidation of the electron and momentum transfer phenomena at both rigid and deformable interfaces in finely (micro nano, atto) dispersed systems. The electroviscoelastic behavior of e.g. liquid/liquid interfaces (emulsions and double emulsions) is based on three forms of "instabilities"; these are rigid, elastic, and plastic. The events are understood as interactions between internal (immanent) and external (incident) periodical physical fields. Since the events at the interfaces of finely dispersed systems must be considered at the molecular, atomic, and/or entities level, it is inevitable to introduce the electron transfer phenomenon beside the classical heat, mass and momentum transfer phenomena commonly used in chemical engineering. Three possible mathematical formalisms have been derived related to this physical formalism, i.e. to the developed theory of electroviscoelasticity. The first is tension tensor model, where the normal and tangential forces are considered, only in mathematical formalism, regardless to their origin (mechanical and/or electrical). The second is van der Pol derivative model. Finally, the third model comprise an effort to generalize the previous van der Pol differential equations, both, linear and nonlinear; the ordinary time derivatives and integrals are now replaced by corresponding fractional-order time derivatives and integrals of order p lt 1. Both, the presented model and theory can facilitate the understanding of entrainment problems in solvent extraction, developed interfaces in colloid and interface science, chemical and biological sensors, electro analytical methods, biology/biomedicine (hematology, genetics and electroneuro-physiology)

Colloid electrohydrodynamics

This brief extracted review presents the recent development in basic and applied science and engineering of finely dispersed particles and related systems in general, but more profound and in-depth treatise are related to the liquid-liquid finely dispersed systems, i.e. emulsions and double emulsions. Twenty-five years ago, the idea, at first very fogy, came out from the pilot plant experiments related to the extraction Of uranium from wet phosphoric acid. In particular the solution of the entrainment problems, breaking of emulsions/double emulsions, as the succession of the extraction and stripping operations/processes, was performed In this pilot plant, secondary liquid-liquid phase separation loop was designed and carried out. The loop consisted of a lamellar coalescer and four flotation cells in series. Central equipment in the loop, relevant to this investigation, was the lamellar coalescer. The phase separation in this equipment is based on the action of external forces of mechanical and/or electrical origin, while adhesive processes at the inclined filling plates occur. Since many of related processes, e.g. adhesive processes, rupture processes and coalescence, were not very well understood, deeper research of these events and phenomena was a real scientific challenge

Effects of system parameters and inorganic salts on the photodecolourisation of textile dye Reactive Blue 19 by UV/H2O2 process

The photodecolourisation of textile dye Reactive Blue 19 (RB 19), an anionic anthraquinone dye of the reactive class, was investigated using UV radiation in the presence of H2O2 in a batch photo-reactor with low-pressure mercury lamps. The effects of the system parameters: initial pH, initial dye concentration, concentration of peroxide and radiation intensity, as well as the presence of salts, (NaCl, Na2SO4, NaNO3, NaH2PO4) on dye decolourisation was examined. Increasing the initial pH resulted in an increase in decolourisation efficiency. Results showed that with an increase of dye concentration from 10 to 100 mg∙ℓ–1, the efficiency of the process decreases. The highest decolourisation rates were noted at H2O2 concentrations of approximately 30 mmol∙ℓ–1. The increase of radiation intensity from 730 to 1 950 μW∙cm–2, linearly increases decolourisation efficiency. The inorganic ions investigated have inhibiting effects on RB 19 decolourisation by the UV/H2O2 process with inhibition intensities in the following order: H2PO4– > NO3– > SO42– > Cl–. This study has shown that the UV/H2O2 process is a promising technology for degradation of RB 19 in water and wastewater