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1
Content available remote Separation of HCl from the mixture of KCl and HCl using membrane distillation
100%
Tomaszewska M. , Mientka A.
Polish Journal of Chemical Technology
|
2008
|
tom 10
|
nr 2
27-32
EN
Membrane distillation (MD) was applied for the concentration of solutions containing hydrochloric acid and potassium chloride. The studies of the concentration and separation of HCl through the hydrophobic membrane were performed. In the investigations plate and frame or capillary modules, equipped with membranes from polytetrafluoroethylene and polypropylene were applied, respectively. The feed temperature amounted to 333 K or 343 K and permeate 293 K at the inlet of the module. Under the MD operation conditions the transfer of water vapour and hydrogen chloride from potassium chloride and hydrochloric acid solutions through the hydrophobic membranes took place, whereas the potassium chloride as a nonvolatile component underwent concentration in the feed. The influence of acid concentration and salt presence in the feed on the HCl molar flux through the membrane was systematically studied. The increase of the temperature and salt concentration in the feed caused higher partial pressure volatile of HCl and the resultant HCl Flux through a membrane was higher.During MD for the initial concentration in the feed equal 50 g KCl/dm3 and 40g HCl/dm3, at the feed temperature 343K, the permeate flux decreased from 353 dm3/m2d to 289 dm3/m2d, whereas the HCl flux increased to 6 mol/m2d for the capillary module. At higher KCl concentration in the feed, amounting to 100g KCl/dm3 and under the same operation conditions, the permeate flux decreased to 285 dm3/m2d, but the molar flux HCl increased to 18 mol/m2d. The results were compared with the data obtained for the plate and frame module.
2
Content available remote Badania destylacji membranowej wody podziemnej wstępnie oczyszczonej chemicznie w osadniku kontaktowym
100%
Gryta M.
Przemysł Chemiczny
|
2007
|
tom T. 86, nr 11
1101-1106
3
Content available remote Odzyskiwanie kwasu solnego z mieszaniny HCl-H2SO4
80%
Tomaszewska M. U. , Surowik A. , Mientka A. M.
Przemysł Chemiczny
|
2008
|
tom T. 87, nr 5
596-599
4
Content available Separation of HCl from the mixture of KCl and HCl using membrane distillation
80%
Tomaszewska M. , Mientka A.
Polish Journal of Chemical Technology
|
2008
|
tom Vol. 10, nr 2
27-32
EN
Membrane distillation (MD) was applied for the concentration of solutions containing hydrochloric acid and potassium chloride. The studies of the concentration and separation of HCl through the hydrophobic membrane were performed. In the investigations plate and frame or capillary modules, equipped with membranes from polytetrafluoroethylene and polypropylene were applied, respectively. The feed temperature amounted to 333 K or 343 K and permeate 293 K at the inlet of the module. Under the MD operation conditions the transfer of water vapour and hydrogen chloride from potassium chloride and hydrochloric acid solutions through the hydrophobic membranes took place, whereas the potassium chloride as a nonvolatile component underwent concentration in the feed. The influence of acid concentration and salt presence in the feed on the HCl molar flux through the membrane was systematically studied. The increase of the temperature and salt concentration in the feed caused higher partial pressure volatile of HCl and the resultant HCl Flux through a membrane was higher. During MD for the initial concentration in the feed equal 50 g KCl/dm3 and 40g HCl/dm3, at the feed temperature 343K, the permeate flux decreased from 353 dm3/m2d to 289 dm3/m2d, whereas the HCl flux increased to 6 mol/m2d for the capillary module. At higher KCl concentration in the feed, amounting to 100g KCl/dm3 and under the same operation conditions, the permeate flux decreased to 285 dm3/m2d, but the molar flux HCl increased to 18 mol/m2d. The results were compared with the data obtained for the plate and frame module.
5
Content available remote Separation of volatile compounds from fermentation broth by membrane distillation
80%
Gryta M. , Barancewicz M.
Polish Journal of Chemical Technology
|
2011
|
tom 13
|
nr 3
56-60
EN
The diluted ethanol solutions and fermentation broth (Saccharomyces cerevisiae) were separated by membrane distillation (MD). Hydrophobic macroporous (pore size 0.2 μm) capillary polypropylene membranes, Accurel PP V8/2 HF and Accurel PP S6/2, were used for these studies. The MD process can be successfully applied to remove the volatile components from the fermentation broth. Besides ethanol, propionic and acetic acids were moved from the broth to the distillate. Therefore, the course of the fermentation carried out in a membrane distillation bioreactor considerably accelerate its rate and increase the efficiency by a selective removal of fermentation products. It was found that the broth subjected to the separation did not affect the hydrophobic properties of the polypropylene membrane assembled in the MD modules.
6
Content available remote The investigation of ethanol separation by the membrane distillation process
80%
Tomaszewska M. , Białończyk L.
Polish Journal of Chemical Technology
|
2011
|
tom 13
|
nr 3
66-69
EN
Separation of ethanol from solutions with different concentrations in a BIOTRON bioreactor integrated with the direct contact membrane distillation system has been investigated. The experiments were carried out using immersed, capillary polypropylene membranes. The permeability of the membrane at the feed inlet temperatures of 308, 318 and 333K was determined. The permeate and ethanol flux was strongly affected by the vapour pressure which increased with the feed temperature and it was also associated with ethanol concentration in the feed. It was found that the membrane distillation can be successfully applied for the separation of volatile components such as ethanol.
7
Content available remote Uzdatnianie wody do celów kotłowych metodą destylacji membranowej
80%
Zakrzewska-Trznadel G. , Harasimowicz M. , Chmielewski A. G.
Przemysł Chemiczny
|
1999
|
tom T. 78, nr 5
181-184
8
Content available remote Scaling diminution by heterogeneous crystallization in a filtration element integrated with membrane distillation module
80%
Gryta M.
Polish Journal of Chemical Technology
|
2009
|
tom 11
|
nr 2
60-65
EN
Water desalination by membrane distillation is restricted by calcium carbonate precipitation on the membrane surface, what resulted in a progressive decline of the permeate flux. The module rinsing by HCl solution removed this deposit, however, such operation could cause the membrane wettability, associated with lowering of the permeate flux. This phenomenon was inhibited when the membrane modules with prefiltration element, assembled directly at the inlet to module, were used. The salt deposits were formed mainly on the surface of the filtration element (nets area constituted over 10% of the membranes area), what protected the membranes assembled inside the module. The filter efficiency decreased when the deposit layer covered the entire surface of pre-filter element, and after a few hours (period of 10-20 h) the formation of crystallite on the membrane surface was also observed. Therefore, the formed deposit was systematically removed (at every 5 h) from this pre-filter by 3 wt.% HCl solutions. The periodical rinsing of nets by acid did not have a negative influence on the membrane
9
Content available Water demineralization by membrane distillation utilizing cooling water from municipal waste incinerator
80%
Gryta M.
Polish Journal of Chemical Technology
|
2018
|
tom Vol. 20, nr 3
65--74
EN
The membrane distillation performance was studied for production of demineralized water from surface water (river). Hot water from cooling water system of municipal waste incinerator was considered as an energy source for membrane distillation. The integration of membrane installation with such cooling water system allows to re-use up to 18 kW per 1 m2  of the membranes. The studies were performed with the application of polypropylene capillary membranes Accurel PP S6/2. The membrane modules were supplied with the feed heated to a temperature of 310 K and 330 K. The permeate flux obtained for these temperatures was 2.8 and 9.7 L/m2  h, and the distillate conductivity was 6 and 4 S/cm, respectively. The water demineralisation process was carried out for 1200 h without module cleaning. The behaviour of the permeate flux and distillate conductivity indicate that used membranes maintained their non-wettability over tested period. The performed SEM-EDS examinations confirmed, that the deposits did not fill the pores and were mainly formed on the membrane surface. The scaling intensity was definitely smaller for lower temperature (310 K) of the feed. The amorphous deposits containing beside Ca also substantial amounts of the Si were mainly formed under these conditions, whereas at higher feed temperature dominated CaCO3  scaling.
10
Content available remote The influence of the process parameters on the permeate flux in the osmotic membrane distillation
70%
Sasim M. , Gryta M.
Polish Journal of Chemical Technology
|
2006
|
tom Vol. 8, nr 2
12-15
EN
Osmotic membrane distillation is a novel variant of membrane distillation process proposed for the removal of water from dilute aqueous solutions, such as liquid foods. The effect of various process parameters, such as the concentration, the flow rates and the temperature of the feed and the osmotic solution on the permeate flux was evaluated. The NaCl and CaCl2 salts were used as a solute for the preparation of the osmotic solution. The hydrophobic capillary polypropylene membranes were used in these studies. Within the tested range of the process parameters the permeate fluxes can be significantly improved (over two-fold) by: replacing the NaCl by CaCl2 solution and enhancing the process temperature from 298 to 313 K or heating the feed by 5 K over the temperature of the osmotic solution. Smaller influence was found to stream the flow rates, the permeate flux increases by 15% when the flow increased by five-fold.
11
Content available remote Water purification by a direct contact membrane distillation
60%
Gryta M.
Polish Journal of Chemical Technology
|
2005
|
tom Vol. 7, nr 3
35-39
EN
Membrane distillation for the purification of water was proposed. The obtained distillate was the demineralized water with the electrical conductivity in the range of 1.3 - 2.5 mS cm-1. The polypropylene membrane wettability during long-term investigations has been performed. A gradual decline of the permeate flux, from 650 to 390 dm3/m2d was observed as a consequence of the fouling phenomenon. The CaCO3 deposit formed on the membrane surface caused a decrease of the membrane permeability and a partial membrane wetting.
12
Content available Technological improvement of the Sorghum saccharatum syrup production by membrane technologies
60%
Chibrikov V. , Vakuliuk P. , Hryhorenko N. , Gunko S. , Sobczuk H.
Journal of Water and Land Development
|
2022
|
tom no. 54
131--137
EN
Easy-to-handle and effective methods of juice clarification and concentration by membrane technologies are still under exploration. The current article presents results of research on the technological development of an alternative natural sweetener of high biological value and improved organoleptic properties. Sorghum saccharatum stem juice is used in research. It is pre-clarified enzymatically with α-amylase and glucoamylase, clarified by ultrafiltration, and concentrated by the direct contact membrane distillation in various temperature ranges. The study shows the efficacy of membrane methods for improving juice purity, total soluble solids (TSS), and total sugar (TS) content in the syrup obtained. Clarification depends on membrane characteristics at the beginning of the process, as there are no differences at the end of it. Juice concentration at high-temperature differences allows to accelerate the process by approx. 60% comparing to low-temperature differences. A lower temperature difference (∆Т = 20-30°С) in the concentration process results in a longer process and syrup acidisation, whereas a higher temperature difference (∆Т = 70°С) affects physicochemical properties of syrup due to local overheating and formation of Maillard reaction products. The juice concentration at ∆Т = 50-60°С allows to obtain high values of total soluble solids without significant degradation of physicochemical and organoleptic properties.
13
Content available Separation of volatile compounds from fermentation broth by membrane distillation
60%
Gryta M. , Barancewicz M.
Polish Journal of Chemical Technology
|
2011
|
tom Vol. 13, nr 3
56-60
EN
The diluted ethanol solutions and fermentation broth (Saccharomyces cerevisiae) were separated by membrane distillation (MD). Hydrophobic macroporous (pore size 0.2 ěm) capillary polypropylene membranes, Accurel PP V8/2 HF and Accurel PP S6/2, were used for these studies. The MD process can be successfully applied to remove the volatile components from the fermentation broth. Besides ethanol, propionic and acetic acids were moved from the broth to the distillate. Therefore, the course of the fermentation carried out in a membrane distillation bioreactor considerably accelerate its rate and increase the efficiency by a selective removal of fermentation products. It was found that the broth subjected to the separation did not affect the hydrophobic properties of the polypropylene membrane assembled in the MD modules.
14
Content available remote Gas desulfurization in the hybrid system absorption-membrane distillation
60%
Lewicki M. , Gryta M.
Polish Journal of Chemical Technology
|
2004
|
tom Vol. 6, nr 4
47-50
EN
The system for gas purification by the absorption of SO2 in a solution of Fe (II) sulphate (VI) proceeding simultaneously with the catalytic oxidation of SO2 to sulfuric acid is presented in this work. It has been found that FeSO4ź7H2O formed in the process of titanium white (TiO2) manufacture is an active catalyst in the oxidation process of SO2 to H2SO4. This salt contains the admixture of salts of other metals such as Mn, Cu, Cr, Ni, V and Ti. A combination of the absorption process with the concentration of a post-absorption solution by membrane distillation allowed obtaining a solution containing 680 g H2SO4 dm (-3).
15
Content available Scaling diminution by heterogeneous crystallization in a filtration element integrated with membrane distillation module
60%
Gryta M.
Polish Journal of Chemical Technology
|
2009
|
tom Vol. 11, nr 2
60-65
EN
Water desalination by membrane distillation is restricted by calcium carbonate precipitation on the membrane surface, what resulted in a progressive decline of the permeate flux. The module rinsing by HCl solution removed this deposit, however, such operation could cause the membrane wettability, associated with lowering of the permeate flux. This phenomenon was inhibited when the membrane modules with prefiltration element, assembled directly at the inlet to module, were used. The salt deposits were formed mainly on the surface of the filtration element (nets area constituted over 10% of the membranes area), what protected the membranes assembled inside the module. The filter efficiency decreased when the deposit layer covered the entire surface of pre-filter element, and after a few hours (period of 10-20 h) the formation of crystallite on the membrane surface was also observed. Therefore, the formed deposit was systematically removed (at every 5 h) from this pre-filter by 3 wt.% HCl solutions. The periodical rinsing of nets by acid did not have a negative influence on the membrane.
16
Content available remote Studies on the application of membrane technology in chemical industry
60%
Tomaszewska M.
Polish Journal of Chemical Technology
|
2005
|
tom Vol. 7, nr 3
101-107
EN
The application of membrane technology in industry especially for water treatment for special proposes has become very attractive over the last decades. The studies performed in our Institute on the surface water treatment as well as the waste water treatment, particularly of industrial origin, using the pressure-driven membrane processes and membrane distillation are presented.
17
Content available Concentration of FeSO4 spent solutions by membrane distillation
60%
Gryta M.
Polish Journal of Chemical Technology
|
2007
|
tom Vol. 9, nr 2
15-18
EN
The possibility of potential application of membrane distillation for the concentration of waste salt solutions has been presented in this work. It was found that the oxidation of iron compounds takes place during the process that was associated with the formation of a layer of oxides on the membrane surface. A fast decline of the permeate flux was observed due to the scaling phenomena. The problem of scaling was eliminated by the acidification with H2SO4 of the feed to the pH value of 2.
18
Content available remote Otrzymywanie wody zdemineralizowanej metodą destylacji membranowej
60%
Gryta M.
Przemysł Chemiczny
|
2018
|
tom T. 97, nr 8
1409--1411
PL
Przedstawiono wyniki badań otrzymywania wody zdemineralizowanej z wody powierzchniowej w procesie destylacji membranowej. Proces prowadzono stosując kapilarne membrany wykonane z polipropylenu. Badano wpływ temperatury nadawy (313-333 K) oraz stopnia odzysku wody (75-90%) na powstawanie osadów na powierzchni membran (scaling) oraz na wydajność procesu. Niezależnie od stężenia nadawy uzyskiwano czystą wodę o małej przewodności właściwej. Prowadzenie procesu przy wysokim stopniu odzysku (90%) spowodowało spadek wydajności procesu z powodu obecności osadów na powierzchni membran. Intensywność zanieczyszczenia membran znacznie zmniejszono, gdy wodę zasilająca podgrzewano tylko do 313 K, a współczynnik odzysku wody wynosił 75%. Morfologię oraz skład osadów badano metodą mikroskopii skaningowej połączonej z mikroanalizą rentgenowską.
EN
Membrane distn. was used for the prodn. of demineralized H2O from surface water. The effect of feed temp. and the degree of H2O recovery on the scaling layer formed on the membrane surface and process effectiveness was evaluated. A high H2O recovery degree (90%) was achieved, but the accelerated formation of deposits on the membrane surface (scaling) was obsd., esp. for feed temp. 333 K and H2O recovery degree above 75%. The morphol. and compn. of the filter cake was studied by scanning electron microscopy coupled with energy-dispersing spectrometry.
19
Content available remote Environmental fracture of polypropylene membranes used in membrane distillation process
60%
El Fray M. , Gryta M.
Polimery
|
2008
|
tom T. 53, nr 11-12
865-870
EN
The thermal and mechanical stability of different capillary polypropylene (PP) membranes used in the membrane distillation (MD) process were investigated. Membranes differed in storage time from the manufacturing (from 1 to 8 years). Small changes in polymers crystallinity, melting temperature (Tm) and crystallization temperature (Tc) were detected as the storage time of membranes increased. This can be assigned to the crystal growth in amorphous phase of PP. However, independently on the storage time the brand-new membranes were found to be flexible and elastic and capable to bending without fracture. The MD process was carried out either continuously or continuously/periodically. Distilled water and NaCl solutions were used as feeds in MD process. It was found that PP membranes are loosing their flexibility and become brittle during long-term usage in MD modules, and as a consequence, they show susceptibility to cracking and fracture. These effects were more significant when NaCl solutions were used as feeds.
PL
W pracy przedstawiono wyniki badań stabilności mechanicznej i termicznej (rys. 3) kapilarnych membran polipropylenowych Accurel PP S6/2, które zastosowano w procesie destylacji membranowej (MD) (rys. 1 i 2). Badane membrany różniły się czasem przechowywania od momentu ich produkcji (od rocznych do ośmioletnich). Nowe membrany przed zastosowaniem w procesie MD były elastyczne i giętkie, co pozwalało je odkształcać bez zniszczenia. Stwierdzono, że wraz z czasem przechowywania membran zmienia się krystaliczność polimerów oraz ich temperatury topnienia (Tm) i temperatury krystalizacji (Tc) (rys. 4, tabela 1). Może to być związane ze wzrostem krystalitów w fazie amorficznej polipropylenu. Proces destylacji membranowej prowadzono w sposób ciągły lub ciągły/okresowy. Do zasilania instalacji MD zastosowano różne media (wodę destylowaną i roztwory NaCl). Stwierdzono, że podczas długotrwałej eksploatacji modułów MD zamontowane w nich membrany polipropylenowe tracą swoją pierwotną elastyczność, stają się sztywne i w efekcie są bardzo podatne na pękanie i zniszczenie (rys. 5). Zmiany właściwości polimerów były wyraźniejsze, gdy jako nadawę zastosowano roztwory NaCl (rys. 7, tabele 2 i 3). Częste zmiany temperatury membran kapilarnych spowodowały powstanie naprężeń termicznych, czego efektem było powstawanie szczelin na powierzchni membran (rys. 6).
20
Content available remote Membrane distillation for environment protection
60%
Tomaszewska M. , Gryta M. , Morawski M. W.
Polish Journal of Chemical Technology
|
2000
|
tom Vol. 2, nr 1
32-37
EN
Membrane distillation (MD) is still considered as a new promising process of separation of aqueous solutions. The driving force is a difference of partial pressure caused by temperatures and compositions of solutions separated by a microporous membrane. The main features of the process are high selectivity for solutions of non-volatile compounds and the possibility of utilization of waste heat or alternative energy sources for heating of the feed. The principles of MD and the possibility of its application for desalination and wastewater treatment are considered.
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