Research Interests:
Research Interests:
Research Interests:
Pervap™ 2200, 2201, 2216, 2255, and 2510 hydrophilic, PVA membranes were investigated in pervaporation of water-tetrafluoropropanol mixtures. Physicochemical properties of membranes were characterized by determining the contact angle (CA)... more
Pervap™ 2200, 2201, 2216, 2255, and 2510 hydrophilic, PVA membranes were investigated in pervaporation of water-tetrafluoropropanol mixtures. Physicochemical properties of membranes were characterized by determining the contact angle (CA) of water and glycerol and the surface free energy (SFE). The separation and transport properties of membranes were determined during vacuum pervaporation in contact with water-TFP mixtures containing up to 22 wt.% water. It was found that all membranes were hydrophilic (CA < 90°) and the polar component of SFE was much higher than the dispersive one. The apparent activation energy for water transport was very high (Eapp = 81.3 kJ/mol), indicated that water transport is activated thermally. Pervap™ membranes were very selective during the dehydration process of TFP. In contact with the Pervap™ 2200, 2201, and 2216 permeate contained practically pure water, regardless the feed composition. The process separation index (PSI) for Pervap™ 2200 and 2216 was close to 5000 kg m−2 h−1, suggesting that both membranes can be efficiently applied in the batch pervaporation process for TFP dehydration.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
This paper relates e ectiveness of membrane enhanced drying process to rheology of yeast suspension. It describes relations of suspension viscosity with respect to the cell concentration, temperature, and shear rate. The collected data... more
This paper relates e ectiveness of membrane enhanced drying process to rheology of yeast suspension. It describes relations of suspension viscosity with respect to the cell concentration, temperature, and shear rate. The collected data prove that the rheological behaviour is very complicated and depends on the three variables studied. It is demonstrated that transition from shear-thinning to shear-thickening phenomenon is mostly temperature-controlled and attributed to highly concentrated suspension only. At 30oC, a suspension with unexpectedly low viscosity was found which triggered the search for process parameters that allow keeping low values of suspension viscosity.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
The "capacitive mixing" (CAPMIX) is one of the techniques aimed at the extraction of energy from the salinity difference between sea and rivers. It is based on the rise of the voltage between two electrodes, taking place when... more
The "capacitive mixing" (CAPMIX) is one of the techniques aimed at the extraction of energy from the salinity difference between sea and rivers. It is based on the rise of the voltage between two electrodes, taking place when the salt concentration of the solution in which they are dipped is changed. We study the rise of the potential of activated carbon electrodes in NaCl solutions, as a function of their charging state. We evaluate the effect of the modification of the materials obtained by adsorption of charged molecules. We observe a displacement of the potential at which the potential rise vanishes, as predicted by the electric double layer theories. Moreover, we observe a saturation of the potential rise at high charging states, to a value that is nearly independent of the analyzed material. This saturation represents the most relevant element that determines the performances of the CAPMIX cell under study; we attribute it to a kinetic effect.
Research Interests:
Research Interests:
The impending crisis posed by water stress and poor sanitation represents one of greatest human challenges for the 21st century, and membrane technology has emerged as a serious contender to confront the crisis. Yet, whilst there are... more
The impending crisis posed by water stress and poor sanitation represents one of greatest human challenges for the 21st century, and membrane technology has emerged as a serious contender to confront the crisis. Yet, whilst there are countless texts on wastewater treatment and on membrane technologies, none address the boron problem and separation processes for boron elimination. Boron Separation Processes fills this gap and provides a unique and single source that highlights the growing and competitive importance of these processes. For the first time, the reader is able to see in one reference work the state-of-the-art research in this rapidly growing field. The book focuses on four main areas: * Effect of boron on humans and plants* Separation of boron by ion exchange and adsorption processes* Separation of boron by membrane processes* Simulation and optimization studies for boron separation . Provides in one source a state-of-the-art overview of this compelling area . Reviews the environmental impact of boron before introducing emerging boron separation processes . Includes simulation and optimization studies for boron separation processes . Describes boron separation processes applicable to specific sources, such as seawater, geothermal water and wastewater
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
In the agriculture and agri-food chain industries there is a strong nexus between food, energy and water as it consumes about one-third of the global energy and 80-90% of the world’s freshwater pro ...
Research Interests:
In this study, polypropylene porous membranes with an average pore size of 1.25 µm were modified by barrier discharge plasma. Next, molecularly imprinted layers with an imprint of diethyl phthalate (DEP) ware grafted of their surface. In... more
In this study, polypropylene porous membranes with an average pore size of 1.25 µm were modified by barrier discharge plasma. Next, molecularly imprinted layers with an imprint of diethyl phthalate (DEP) ware grafted of their surface. In order to optimize the composition of the modifying mixture various solvents, the ratios of functional monomers and the cross-linking monomer as well as various amounts of phthalate were verified. It was shown that the most effective membranes were obtained during polymerization in n-octane with the participation of functional monomers in the ratio 3:7 and the amount of phthalate 7 wt.%. The membranes were tested in the filtration process as well as static and dynamic sorption. In all of these processes, the imprinted membranes showed better properties than those without the imprint. The diethyl phthalate retention coefficient was 36.12% for membranes with a grafting yield of 1.916 mg/cm2. On the other hand, DEP static sorption for the imprinted memb...
Research Interests:
Research Interests:
Research Interests:
WOS: 00033701830000
Research Interests:
Research Interests:
Research Interests: Environmental Engineering, Chemical Engineering, Materials Science, Chemistry, Physical Chemistry, and 12 moreNanotechnology, Multidisciplinary, Activated Carbon, Desalination, Porosity, Water Desalination, Nanoscience, Capacitive Deionization, Carbon Fibers, Electrode, Carbide Derived Carbon, and Mesoporous Material
Research Interests:
Research Interests:
The paper considers properties of porous membranes modified by action of nitrogen plasma. The membrane material was polysulfone — the polymer most frequently used in production of ultrafiltration membranes. It is shown that 2.45 GHz... more
The paper considers properties of porous membranes modified by action of nitrogen plasma. The membrane material was polysulfone — the polymer most frequently used in production of ultrafiltration membranes. It is shown that 2.45 GHz nitrogen plasma generates various kinds of surface functionalities both of acidic and basic character. The surface changes during the first week after plasma treatment, some
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
The presented paper is a peer-review of plasma action on porous polymer membranes. Considering the plasma medium the discussion is split in two parts: i) the first shows some effects caused by action of non-polymerizing gases, i.e.... more
The presented paper is a peer-review of plasma action on porous polymer membranes. Considering the plasma medium the discussion is split in two parts: i) the first shows some effects caused by action of non-polymerizing gases, i.e. polymer etching and/or alteration of surface character, and, ii) the second covers action of plasma reagents resulted in the deposition of polymer layers.
Research Interests:
Research Interests: Chemical Engineering, Materials Science, Membranes, Nanofibers, Electrospinning, and 15 moreComposite Materials, Medicine, Membrane Technology, Membrane Separation Technology, Fouling, Nanofiber, Composite Nanofibers, Nanocomposite, Plasma, Biofouling, Membrane, Nanofibers Electrospun, Membrane Filtration, Oil Separation, and Nanospider
Several methods for membrane modification have been presented. Chemical modification of a neat polymer followed by membrane formation and modification of just formed membranes have been compared to plasma action. The following plasma... more
Several methods for membrane modification have been presented. Chemical modification of a neat polymer followed by membrane formation and modification of just formed membranes have been compared to plasma action. The following plasma modes are discussed in detail: treatment with non-polymerizable gases, treatment with vapors and plasma initiated grafting. Some examples of modified membrane properties are given. Finally, it was concluded that plasma treatment offers the fastest, environment friendly and versatile method that allows tailoring brand new membranes.
Research Interests: Engineering, Environmental Engineering, Chemical Engineering, Materials Science, Chemistry, and 15 moreOrganic Chemistry, Physical Chemistry, Nanotechnology, Medicine, Grafting, Nanoscience, Plasma, Plasma Treatment, Modification, Nanostructure, Membrane, CHEMICAL SCIENCES, Environment, Chemical Modification, and Gas
Research Interests:
The effect of NH3 and NH3/Ar plasma on ultrafiltration polysulfone membranes have been studied. Results of contact angle, FTIR–ATR and X-ray photoelectron spectroscopy experiments clearly showed that both plasmas introduced hydrophilic,... more
The effect of NH3 and NH3/Ar plasma on ultrafiltration polysulfone membranes have been studied. Results of contact angle, FTIR–ATR and X-ray photoelectron spectroscopy experiments clearly showed that both plasmas introduced hydrophilic, nitrogen- and oxygen-containing moieties on the polymer surface and that NH3/Ar plasma was more efficient. That plasma was also more aggressive––signs of strong etching could be seen on the