Claudia Koncsag - Academia.edu (original) (raw)
Papers by Claudia Koncsag
chemicalbulletin.ro
... 3. ***, http://pleurotus.daky.ro/ciupercarie\_pleurotus.htm 4. Hasan, SDM, Costa, JAV, Sanzo,A... more ... 3. ***, http://pleurotus.daky.ro/ciupercarie_pleurotus.htm 4. Hasan, SDM, Costa, JAV, Sanzo,AVL, Biotechnology Techniques, Vol.12 (10), 998, 787 ... 8. Foong, CW, Krishnaiah, K., Janaun, J., Subbarao, D. and Prabhakar, A., Industrial Crops and Products, vol.30, 2009, 227-234. ...
Energies
Bioethanol and dimetyl carbonate (DMC) are considered alternative fuels and additives to the synt... more Bioethanol and dimetyl carbonate (DMC) are considered alternative fuels and additives to the synthesis compounds used now, since bioethanol is a biofuel and dimethyl carbonate (DMC) is non-toxic, biodegradable and can be produced in a cleaner way. In this study, the effect of adding dimethyl carbonate (DMC) and ethanol to gasoline on the volatility was investigated. The volatility was the main goal of this research but also, the effect on the antiknock properties was studied. Mixtures of gasoline with DMC or with bioethanol were prepared in different proportions of additive: 3%, 6% and 9% v/v. Additionally, mixtures with 3% v/v ethanol plus 3% or 6% v/v DMC, and3% DMC plus 6% v/v ethanol were prepared. For the volatility evaluation, the ASTM distillation curve and vapor pressure of these mixtures were determined experimentally in order to predict the performance of the resulting fuels. When adding oxygenated compounds, the increase in vapor pressure was proportional to the additive ...
Applied Mathematical Modelling, 2007
The mathematical model for estimating the mass transfer coefficients for the ethanethiol extracti... more The mathematical model for estimating the mass transfer coefficients for the ethanethiol extraction from gasoline, with alkaline solutions was established by processing the data obtained in a laboratory and in a pilot plant experiment. It allows the estimation of overall mass transfer coefficients, taking into account the dispersed phase velocity, the concentration of NaOH solution, the specific area and the porosity of the packing. The model's parameters were statistical tested in order to confirm the accuracy of the model.
Rheological behaviour of aqueous suspensions of C. barbata and U. lactuca was studied at differen... more Rheological behaviour of aqueous suspensions of C. barbata and U. lactuca was studied at different values of temperature (25, 50 °C), cellulase/dried macroalgae ratio (0, 16 U/mgdma), and suspension mass concentration (5-15%). At 25 °C, the suspensions without cellulase obeyed the Ostwald-de Waele power law and their apparent viscosities (0.25-15.31 Pas for C. barbata and 0.04-5.35 Pas for U. lactuca) increased with macroalga concentration, whereas those containing cellulase behaved as Bingham plastics and their viscosities (0.113-0.141 Pas) were invariant with macroalga species and concentration. At 50 °C, all suspensions were power law fluids with similar apparent viscosities (0.35-50.09 Pas).
Ovidius University Annals of Chemistry, 2020
Cellulose fibres are known for their good mechanical properties, therefore they are used as fille... more Cellulose fibres are known for their good mechanical properties, therefore they are used as fillers in structural composite materials, including as nanofibrils in nanomaterials. Also, they are biocompatible, non-toxic and biodegradable, reason for their use in the food industry as packaging materials or in obtaining medical materials. One source of cheap, easy- to- extract cellulose is the algal mass of Ulva lactuca, one of the most frequent species found in the Black Sea. In this study, cellulose extraction from Ulva lactuca was achieved by a simple low cost physical-chemical treatment. Freshly harvested seaweed was dried at 45 °C for 48 hours, transformed into a fine powder in order to increase the contact surface between the solvents and the alga. Extraction of lipids and chlorophyll took place in Soxhlet apparatus with ethanol. Successive steps of chemical treatment, having in view removal of hydrosoluble ulvans, pigments and hemicellulose lead to a yield of 15.36% in dry matter...
Environmental Engineering and Management Journal, 2009
A study was fulfilled concerning the source and the distribution of PAHs in the effluent proceedi... more A study was fulfilled concerning the source and the distribution of PAHs in the effluent proceeding from an oil refinery. The monitoring of the PAHs concentration in the refinery's effluent also was performed during a year long. The practical goal of the work was to observe the complying with the limits imposed by the current legislation and to identify the potential risks of exceeding these limits in the future. For this study, gas chromatographic and HPLC methods were used. The methods were optimized in order to increase the accuracy of the results. The study concludes that up to now the refiner has complied with the limits imposed by the European legislation, due to the good treatment of wastewater. Also, a tendency of 4 ring hydrocarbon content increasing was observed during the cold season, due to the poorer efficiency of the biological step in the wastewater treatment station.
Chemical Engineering and Processing: Process Intensification, 2008
The goal of this work was to find a model for the calculation of the industrial scale column serv... more The goal of this work was to find a model for the calculation of the industrial scale column serving to the extraction of mercaptans from hydrocarbon fractions with alkaline solutions. The work is based on original experiment at laboratory and pilot scale. A simple, easy to handle model with a good resolution was obtained. The equation for the hydrodynamic behaviour of the column shows the dependency of the column capacity on the physical properties of the liquid-liquid system and the geometrical characteristics of the packing. The equation for the mass transfer shows the dependency of the overall mass transfer coefficients on the mercaptans acidity, concentration of the caustic and geometrical characteristics of the packing. The statistical tests applied on the mass transfer coefficients equation gave good results.
Biomass and Bioenergy, 2011
This article proposes a renewable raw material, in this case is used waste palm oil for obtaining... more This article proposes a renewable raw material, in this case is used waste palm oil for obtaining valuable products which are usually resulted from crude oil, a limited resource. The main goal of the research work is to produce high yield of olefins through thermal cracking processes using waste vegetable oils from different uses. A preliminary research was designed for the thermal cracking of waste palm oil in a micropilot plant composed by a metallic, tubular and electrically heated reactor. The process operated at 2 bar, in a temperature range of 450-630 o C and different residence time (120-180-240s). Mass balance allowed us to calculate the products yields. The products obtained from the process were analyzed using Gas-Chromatography. The study concluded that significant olefins yields (up to 10% wt for ethylene and 7 % wt for propylene) can be obtained by increasing temperature and residence time in the reactor.
univ-ovidius.ro
Abstract. Following a previous study about the characterization of crude oils and fractions by co... more Abstract. Following a previous study about the characterization of crude oils and fractions by combining the chromatographic methods, the working method was extended to petroleum fractions from thermocatalytical processes. The present study is limited to fractions with final boiling ...
The reactive distillation is an inovative process representing a solution for the process intensi... more The reactive distillation is an inovative process representing a solution for the process intensification with the posibility of increasing the reactions selectivity with a preference to obtain certain products. In this work, it was studied the influence of the following factors on the esterification of the lactic acid with methanol through reactive distillation: the molar ratio of the reactants and the number of a theoretical plates performed by the column equipped with Raschig rings. The results showed that by using a column with packing equivalent with 4.9 theoretical plates, the yield of methyl lactate increases with the growth of the molar ratio methanol:lactic acid, up to 78.7% for a molar ratio of 3:1. Also, the yield increases with the increasing of theoretical plates number. A linear mathematical model was proposed correlating the methyl lactate yield with the reactants molar ratio and the number of theoretical plates. The model has a pretty good precision (correlation coef...
The monitoring of gaseous emissions in a refinery is complex and difficult task requiring special... more The monitoring of gaseous emissions in a refinery is complex and difficult task requiring special equipment and operators in good physical shape. Some of these emissions could be calculated from other measured data from fixed analysis points. This shall decrease the number of determinations in hazardous circumstances. The authors of this study worked out some equations for the correlation of the main combustion emissions (CO 2, NO x) with the oxygen content of flue gas and the temperature at the stack. Even though the CO 2 emissions could be predicted by stoechiometric calculations, a model based on statistical processing of hundreds of data is easier to apply; this is why, the authors searched for simple and exact equations. The prediction of CO 2 and NO x was made versus the the oxygen content of flue gas and the temperature at the stack, which can be measured with fixed sensors. Finally, the prediction of flue gas emissions can be performed by replacing the costly and dangerous s...
The aim of this study is to evaluate the potential of dried Cystoseira barbata alga for ethanol p... more The aim of this study is to evaluate the potential of dried Cystoseira barbata alga for ethanol production through alcoholic fermentation. The influence of the main factors affecting the fermentation are studied in the frame of a 23 factorial experimental plan. The main factors influencing the process are the fermentation temperature (t from 25 °C to 35 °C), the solid to liquid ratio (S/L from 0.040 g/g to 0.080 g/g), and the cellulase ratio (R from 8 U/g d.m to 16 U/g d.m.). The maximum volatile compounds yield of 0.2808 g/g d.m and ethanol yield of 0.0158 g/g d.m were favored by the following experimental conditions: process temperature of 35 °C, solid to liquid ratio of 0.0415, and enzyme ratio of 16 U/g d.m. A statistical model was used to correlate the product yield with the process factors. Additionally, 19 interesting bioactive compounds were found in the enzymatic hydrolysis and alcoholic fermentation broths which seem likely to maintain natural defence mechanisms against di...
The soil contains naturally some metals. The major metals in soil consists on Fe, Al and Si in co... more The soil contains naturally some metals. The major metals in soil consists on Fe, Al and Si in compunds as iron oxides, alumina and silica[1, 2]. The usual background concentration in soils are: 48-180 mg Al/kg, 11-240 mg Fe/kg and 0.8-67 mg Si/kg. The anthropogenic activities ...
This work aims to the recovery of lignocellulosic waste in an environmentally friendly process, a... more This work aims to the recovery of lignocellulosic waste in an environmentally friendly process, as an alternative to the energyintensive technologies: steam explosion, subcritical and/or supercritical water treatment, gasification through pyrolisis, etc. A study was made to optimize the extraction conditions of potentially valuable compounds in straw degraded by the fungus Pleurotus ostreatus. The effects of solvent nature, temperature and extraction time were quantified by material balances with a special view to the extracts obtained. Confirmation of the effectiveness of the operations was done by spectrophotometric, HPLC and LC-MS analyses. Following this study, a technology localized to the farm was conceived, requiring few craftsmanship and no special utilities, to obtain a semi-product for further processing. A centralized technology could be also taken into account to process the straw by direct extraction with hot solvents, in order to obtain products yields three times high...
This article proposes a renewable raw material, in this case is used waste palm oil for obtaining... more This article proposes a renewable raw material, in this case is used waste palm oil for obtaining valuable products which are usually resulted from crude oil, a limited resource. The main goal of the research work is to produce high yield of olefins through thermal cracking processes using waste vegetable oils from different uses. A preliminary research was designed for the thermal cracking of waste palm oil in a micropilot plant composed by a metallic, tubular and electrically heated reactor. The process operated at 2 bar, in a temperature range of 450-630 C and different residence time (120-180-240s). Mass balance allowed us to calculate the products yields. The products obtained from the process were analyzed using Gas-Chromatography. The study concluded that significant olefins yields (up to 10% wt for ethylene and 7 % wt for propylene) can be obtained by increasing temperature and residence time in the reactor.
The sludge proceeding from oil refineries is different from other types of sludge (e.g. municipal... more The sludge proceeding from oil refineries is different from other types of sludge (e.g. municipal wastewater treatment plants).The presence of hydrocarbon in high concentration (up to 20% wt.) and the high content in metals require adapted analysis methods. Following a previous study on the methods for the determination of metals in sludge and in oil products and residues, we can now propose a new method. This is appropriate for the analysis of metal content in sludge proceeding from the wastewater treatment plants of oil refineries. The novelty consists on the sample preparation for analysis. The preparation has in view the drying followed by the calcination for the hydrocarbon decomposition without exceeding a certain temperature (550 C), thus avoiding the loss of some organometallic compounds in volatiles. Then, the ash is treated with a mixture of acids for complete mineralization. In this mixture, the presence of HF seems to be important. For the complete dissolution of the ash...
The goal of the present work was to develop new lubricating greases from renewable resources, usi... more The goal of the present work was to develop new lubricating greases from renewable resources, using calcium stearate soap as thickener agent dispersed in corn, olive and palm oils. The effects that temperature (in range 20 degrees C-60 degrees C) and concentration of the thickener agent (in range of 10%-30% wt) on the theological properties of these lubricating greases was studied. Also morphological and melting characterization was performed. Due to their consistency, theological behaviour, stability, non-toxicity and waterproof properties, the greases can be used for lubrication purposes in milder conditions such as sealing greases for food equipment or for chassis lubrication.
This paper deals with the applicability of a structural method of analysis (the aniline point met... more This paper deals with the applicability of a structural method of analysis (the aniline point method) for light petroleum fractions like kerosene and jet fuel. As aniline point method requires, mixtures of pure hydrocarbons were usedtypical for the corresponding classes of hydrocarbon within the same range of boiling points, thuse mimicking the petroleum fractions. The structural groups method n-d-M was applied further and the results were compared with those obtained by aniline point method. Results on hydrocarbon mixtures were compared with those for real petroleum fractions. It was demonstrated that chemical composition of kerosene and jet fuel can be determined either by aniline point method with good accuracy or with n-d-M method, both methods having the advantage to be cheap and fast. These methods can be used for intermediate products (raw or hydrogenated) but not for additivated finished products
This is an experimental study of C5/C6 isomerization on Pt/H- zeolite conducted in industrial con... more This is an experimental study of C5/C6 isomerization on Pt/H- zeolite conducted in industrial conditions. The goal of the work was to find the kinetic parameters of the main isomerization reactions, by considering the industrial reactor as an ideal plug flow reactor. This assumption is fair, taking into account the high pressure and low linear velocity of the effluent in the reactor. The kinetic model can be used for the prediction of isomerizate production and quality.
chemicalbulletin.ro
... 3. ***, http://pleurotus.daky.ro/ciupercarie\_pleurotus.htm 4. Hasan, SDM, Costa, JAV, Sanzo,A... more ... 3. ***, http://pleurotus.daky.ro/ciupercarie_pleurotus.htm 4. Hasan, SDM, Costa, JAV, Sanzo,AVL, Biotechnology Techniques, Vol.12 (10), 998, 787 ... 8. Foong, CW, Krishnaiah, K., Janaun, J., Subbarao, D. and Prabhakar, A., Industrial Crops and Products, vol.30, 2009, 227-234. ...
Energies
Bioethanol and dimetyl carbonate (DMC) are considered alternative fuels and additives to the synt... more Bioethanol and dimetyl carbonate (DMC) are considered alternative fuels and additives to the synthesis compounds used now, since bioethanol is a biofuel and dimethyl carbonate (DMC) is non-toxic, biodegradable and can be produced in a cleaner way. In this study, the effect of adding dimethyl carbonate (DMC) and ethanol to gasoline on the volatility was investigated. The volatility was the main goal of this research but also, the effect on the antiknock properties was studied. Mixtures of gasoline with DMC or with bioethanol were prepared in different proportions of additive: 3%, 6% and 9% v/v. Additionally, mixtures with 3% v/v ethanol plus 3% or 6% v/v DMC, and3% DMC plus 6% v/v ethanol were prepared. For the volatility evaluation, the ASTM distillation curve and vapor pressure of these mixtures were determined experimentally in order to predict the performance of the resulting fuels. When adding oxygenated compounds, the increase in vapor pressure was proportional to the additive ...
Applied Mathematical Modelling, 2007
The mathematical model for estimating the mass transfer coefficients for the ethanethiol extracti... more The mathematical model for estimating the mass transfer coefficients for the ethanethiol extraction from gasoline, with alkaline solutions was established by processing the data obtained in a laboratory and in a pilot plant experiment. It allows the estimation of overall mass transfer coefficients, taking into account the dispersed phase velocity, the concentration of NaOH solution, the specific area and the porosity of the packing. The model's parameters were statistical tested in order to confirm the accuracy of the model.
Rheological behaviour of aqueous suspensions of C. barbata and U. lactuca was studied at differen... more Rheological behaviour of aqueous suspensions of C. barbata and U. lactuca was studied at different values of temperature (25, 50 °C), cellulase/dried macroalgae ratio (0, 16 U/mgdma), and suspension mass concentration (5-15%). At 25 °C, the suspensions without cellulase obeyed the Ostwald-de Waele power law and their apparent viscosities (0.25-15.31 Pas for C. barbata and 0.04-5.35 Pas for U. lactuca) increased with macroalga concentration, whereas those containing cellulase behaved as Bingham plastics and their viscosities (0.113-0.141 Pas) were invariant with macroalga species and concentration. At 50 °C, all suspensions were power law fluids with similar apparent viscosities (0.35-50.09 Pas).
Ovidius University Annals of Chemistry, 2020
Cellulose fibres are known for their good mechanical properties, therefore they are used as fille... more Cellulose fibres are known for their good mechanical properties, therefore they are used as fillers in structural composite materials, including as nanofibrils in nanomaterials. Also, they are biocompatible, non-toxic and biodegradable, reason for their use in the food industry as packaging materials or in obtaining medical materials. One source of cheap, easy- to- extract cellulose is the algal mass of Ulva lactuca, one of the most frequent species found in the Black Sea. In this study, cellulose extraction from Ulva lactuca was achieved by a simple low cost physical-chemical treatment. Freshly harvested seaweed was dried at 45 °C for 48 hours, transformed into a fine powder in order to increase the contact surface between the solvents and the alga. Extraction of lipids and chlorophyll took place in Soxhlet apparatus with ethanol. Successive steps of chemical treatment, having in view removal of hydrosoluble ulvans, pigments and hemicellulose lead to a yield of 15.36% in dry matter...
Environmental Engineering and Management Journal, 2009
A study was fulfilled concerning the source and the distribution of PAHs in the effluent proceedi... more A study was fulfilled concerning the source and the distribution of PAHs in the effluent proceeding from an oil refinery. The monitoring of the PAHs concentration in the refinery's effluent also was performed during a year long. The practical goal of the work was to observe the complying with the limits imposed by the current legislation and to identify the potential risks of exceeding these limits in the future. For this study, gas chromatographic and HPLC methods were used. The methods were optimized in order to increase the accuracy of the results. The study concludes that up to now the refiner has complied with the limits imposed by the European legislation, due to the good treatment of wastewater. Also, a tendency of 4 ring hydrocarbon content increasing was observed during the cold season, due to the poorer efficiency of the biological step in the wastewater treatment station.
Chemical Engineering and Processing: Process Intensification, 2008
The goal of this work was to find a model for the calculation of the industrial scale column serv... more The goal of this work was to find a model for the calculation of the industrial scale column serving to the extraction of mercaptans from hydrocarbon fractions with alkaline solutions. The work is based on original experiment at laboratory and pilot scale. A simple, easy to handle model with a good resolution was obtained. The equation for the hydrodynamic behaviour of the column shows the dependency of the column capacity on the physical properties of the liquid-liquid system and the geometrical characteristics of the packing. The equation for the mass transfer shows the dependency of the overall mass transfer coefficients on the mercaptans acidity, concentration of the caustic and geometrical characteristics of the packing. The statistical tests applied on the mass transfer coefficients equation gave good results.
Biomass and Bioenergy, 2011
This article proposes a renewable raw material, in this case is used waste palm oil for obtaining... more This article proposes a renewable raw material, in this case is used waste palm oil for obtaining valuable products which are usually resulted from crude oil, a limited resource. The main goal of the research work is to produce high yield of olefins through thermal cracking processes using waste vegetable oils from different uses. A preliminary research was designed for the thermal cracking of waste palm oil in a micropilot plant composed by a metallic, tubular and electrically heated reactor. The process operated at 2 bar, in a temperature range of 450-630 o C and different residence time (120-180-240s). Mass balance allowed us to calculate the products yields. The products obtained from the process were analyzed using Gas-Chromatography. The study concluded that significant olefins yields (up to 10% wt for ethylene and 7 % wt for propylene) can be obtained by increasing temperature and residence time in the reactor.
univ-ovidius.ro
Abstract. Following a previous study about the characterization of crude oils and fractions by co... more Abstract. Following a previous study about the characterization of crude oils and fractions by combining the chromatographic methods, the working method was extended to petroleum fractions from thermocatalytical processes. The present study is limited to fractions with final boiling ...
The reactive distillation is an inovative process representing a solution for the process intensi... more The reactive distillation is an inovative process representing a solution for the process intensification with the posibility of increasing the reactions selectivity with a preference to obtain certain products. In this work, it was studied the influence of the following factors on the esterification of the lactic acid with methanol through reactive distillation: the molar ratio of the reactants and the number of a theoretical plates performed by the column equipped with Raschig rings. The results showed that by using a column with packing equivalent with 4.9 theoretical plates, the yield of methyl lactate increases with the growth of the molar ratio methanol:lactic acid, up to 78.7% for a molar ratio of 3:1. Also, the yield increases with the increasing of theoretical plates number. A linear mathematical model was proposed correlating the methyl lactate yield with the reactants molar ratio and the number of theoretical plates. The model has a pretty good precision (correlation coef...
The monitoring of gaseous emissions in a refinery is complex and difficult task requiring special... more The monitoring of gaseous emissions in a refinery is complex and difficult task requiring special equipment and operators in good physical shape. Some of these emissions could be calculated from other measured data from fixed analysis points. This shall decrease the number of determinations in hazardous circumstances. The authors of this study worked out some equations for the correlation of the main combustion emissions (CO 2, NO x) with the oxygen content of flue gas and the temperature at the stack. Even though the CO 2 emissions could be predicted by stoechiometric calculations, a model based on statistical processing of hundreds of data is easier to apply; this is why, the authors searched for simple and exact equations. The prediction of CO 2 and NO x was made versus the the oxygen content of flue gas and the temperature at the stack, which can be measured with fixed sensors. Finally, the prediction of flue gas emissions can be performed by replacing the costly and dangerous s...
The aim of this study is to evaluate the potential of dried Cystoseira barbata alga for ethanol p... more The aim of this study is to evaluate the potential of dried Cystoseira barbata alga for ethanol production through alcoholic fermentation. The influence of the main factors affecting the fermentation are studied in the frame of a 23 factorial experimental plan. The main factors influencing the process are the fermentation temperature (t from 25 °C to 35 °C), the solid to liquid ratio (S/L from 0.040 g/g to 0.080 g/g), and the cellulase ratio (R from 8 U/g d.m to 16 U/g d.m.). The maximum volatile compounds yield of 0.2808 g/g d.m and ethanol yield of 0.0158 g/g d.m were favored by the following experimental conditions: process temperature of 35 °C, solid to liquid ratio of 0.0415, and enzyme ratio of 16 U/g d.m. A statistical model was used to correlate the product yield with the process factors. Additionally, 19 interesting bioactive compounds were found in the enzymatic hydrolysis and alcoholic fermentation broths which seem likely to maintain natural defence mechanisms against di...
The soil contains naturally some metals. The major metals in soil consists on Fe, Al and Si in co... more The soil contains naturally some metals. The major metals in soil consists on Fe, Al and Si in compunds as iron oxides, alumina and silica[1, 2]. The usual background concentration in soils are: 48-180 mg Al/kg, 11-240 mg Fe/kg and 0.8-67 mg Si/kg. The anthropogenic activities ...
This work aims to the recovery of lignocellulosic waste in an environmentally friendly process, a... more This work aims to the recovery of lignocellulosic waste in an environmentally friendly process, as an alternative to the energyintensive technologies: steam explosion, subcritical and/or supercritical water treatment, gasification through pyrolisis, etc. A study was made to optimize the extraction conditions of potentially valuable compounds in straw degraded by the fungus Pleurotus ostreatus. The effects of solvent nature, temperature and extraction time were quantified by material balances with a special view to the extracts obtained. Confirmation of the effectiveness of the operations was done by spectrophotometric, HPLC and LC-MS analyses. Following this study, a technology localized to the farm was conceived, requiring few craftsmanship and no special utilities, to obtain a semi-product for further processing. A centralized technology could be also taken into account to process the straw by direct extraction with hot solvents, in order to obtain products yields three times high...
This article proposes a renewable raw material, in this case is used waste palm oil for obtaining... more This article proposes a renewable raw material, in this case is used waste palm oil for obtaining valuable products which are usually resulted from crude oil, a limited resource. The main goal of the research work is to produce high yield of olefins through thermal cracking processes using waste vegetable oils from different uses. A preliminary research was designed for the thermal cracking of waste palm oil in a micropilot plant composed by a metallic, tubular and electrically heated reactor. The process operated at 2 bar, in a temperature range of 450-630 C and different residence time (120-180-240s). Mass balance allowed us to calculate the products yields. The products obtained from the process were analyzed using Gas-Chromatography. The study concluded that significant olefins yields (up to 10% wt for ethylene and 7 % wt for propylene) can be obtained by increasing temperature and residence time in the reactor.
The sludge proceeding from oil refineries is different from other types of sludge (e.g. municipal... more The sludge proceeding from oil refineries is different from other types of sludge (e.g. municipal wastewater treatment plants).The presence of hydrocarbon in high concentration (up to 20% wt.) and the high content in metals require adapted analysis methods. Following a previous study on the methods for the determination of metals in sludge and in oil products and residues, we can now propose a new method. This is appropriate for the analysis of metal content in sludge proceeding from the wastewater treatment plants of oil refineries. The novelty consists on the sample preparation for analysis. The preparation has in view the drying followed by the calcination for the hydrocarbon decomposition without exceeding a certain temperature (550 C), thus avoiding the loss of some organometallic compounds in volatiles. Then, the ash is treated with a mixture of acids for complete mineralization. In this mixture, the presence of HF seems to be important. For the complete dissolution of the ash...
The goal of the present work was to develop new lubricating greases from renewable resources, usi... more The goal of the present work was to develop new lubricating greases from renewable resources, using calcium stearate soap as thickener agent dispersed in corn, olive and palm oils. The effects that temperature (in range 20 degrees C-60 degrees C) and concentration of the thickener agent (in range of 10%-30% wt) on the theological properties of these lubricating greases was studied. Also morphological and melting characterization was performed. Due to their consistency, theological behaviour, stability, non-toxicity and waterproof properties, the greases can be used for lubrication purposes in milder conditions such as sealing greases for food equipment or for chassis lubrication.
This paper deals with the applicability of a structural method of analysis (the aniline point met... more This paper deals with the applicability of a structural method of analysis (the aniline point method) for light petroleum fractions like kerosene and jet fuel. As aniline point method requires, mixtures of pure hydrocarbons were usedtypical for the corresponding classes of hydrocarbon within the same range of boiling points, thuse mimicking the petroleum fractions. The structural groups method n-d-M was applied further and the results were compared with those obtained by aniline point method. Results on hydrocarbon mixtures were compared with those for real petroleum fractions. It was demonstrated that chemical composition of kerosene and jet fuel can be determined either by aniline point method with good accuracy or with n-d-M method, both methods having the advantage to be cheap and fast. These methods can be used for intermediate products (raw or hydrogenated) but not for additivated finished products
This is an experimental study of C5/C6 isomerization on Pt/H- zeolite conducted in industrial con... more This is an experimental study of C5/C6 isomerization on Pt/H- zeolite conducted in industrial conditions. The goal of the work was to find the kinetic parameters of the main isomerization reactions, by considering the industrial reactor as an ideal plug flow reactor. This assumption is fair, taking into account the high pressure and low linear velocity of the effluent in the reactor. The kinetic model can be used for the prediction of isomerizate production and quality.