J. Rynkowski - Profile on Academia.edu (original) (raw)

Papers by J. Rynkowski

Portugaliae Electrochimica Acta, 2022

Ethylenediamine (EDA), diethylenetriamine (DETA) and N,N,N',N'-tetrakis (2-hydroxypropyl) ethylen... more Ethylenediamine (EDA), diethylenetriamine (DETA) and N,N,N',N'-tetrakis (2-hydroxypropyl) ethylenediamine (THPrED) are used relatively often in galvanic processes. Tetra-substituted derivatives, such as N, N, N ', N'-tetrakis (2-hydroxyethyl) ethylenediamine, (THEtED) are quite biologically stable and hardly degradable. In recent years, much attention has been devoted to electrochemical oxidation, using anodes with a high over-potential of O2 evolution, such as the boron-doped diamond (BDD). DETA and THPrED electrochemical treatment using a BDD anode was herein studied. The degradation efficiency of the amines was evaluated under different current intensities and reaction times. To determine the products formed in the oxidation process, ion chromatography (IC) was used. A high decrease in the current between the first and the second CV scan indicated the polymer film formation on the BDD electrode surface. Hydroxyl radicals formed at a potential of about 2 V and higher caused further oxidation of the electrode reaction products. It was found that NH4 + , CH3-COOH, N2, EDA, CO2 and NO3-were formed in a short reaction time, and at low current intensity. The mineralization occurred during substrates electrolysis, due to rapid DETA and THPrED decomposition. After 180 min of reaction, αTOC and αN values for DETA were 94% and 18%, respectively. For THPrED, αTOC was 98.6% and αN was 43.6%. Therefore, the electrochemical approach was considered a very promising method in practical application for the treatment of wastewater containing amines.

Selective hydrogenation of a~00, b~00-unsaturated aldehydes in gas phase on Pt/Ga 2 O 3 catalysts

P023 Wpływ pary wodnej na aktywność detekcyjną czujników gazowych wykonanych z Pt-Sn/SnO 2

P.I-7: Zjawisko histerezy w procesie temperaturowo programowanego utleniania tlenku węgla

K-5 Selektywne utlenianie tlenku węgla w obecności wodoru na katalizatorach Pt/nośnik

Układ Pt-Sn/TiO 2 jako materiał do budowy rezystancyjnych czujników lambda. Związek pomiędzy własnościami adsorpcyjnymi a detekcyjnymi

An application of Pt-Sn/SnO 2 catalysts to the formation of semiconductor gas sensors

Effects of alumina-titania supports on the activity of NiMo catalysts

Studies in Surface Science and Catalysis, 1999

ABSTRACT

Radiation Physics and Chemistry, 2013

We determined the minimum hydrotrope concentration (MHC) for SCS. c We analyzed the SCS reactions... more We determined the minimum hydrotrope concentration (MHC) for SCS. c We analyzed the SCS reactions with oxidizing and reducing species. c The rate constants for the oxidation and reduction of SCS were given.

Catalytic and physicochemical properties of Pt/α-GeO2 systems in reaction of selective hydrogenation of α,β-unsaturated aldehydes in a gas phase

Kinetics and Catalysis, 2007

Hydrogenation of crotonaldehyde in a gas phase over Pt/α-GeO2 catalysts was investigated. The sys... more Hydrogenation of crotonaldehyde in a gas phase over Pt/α-GeO2 catalysts was investigated. The systems were characterized by BET, XRD, TPR, TEM, ToF-SIMS, and FTIR methods. The optimum pretreatment parameters were studied. The best catalytic performance shows the catalyst 5 wt % Pt/α-GeO2 (69% selectivity to crotyl alcohol at 200 μmol s−1 g Pt −1 activity and 10% conversion of crotonaldehyde).

Journal of Electroanalytical Chemistry, 2014

Electroreduction behavior of acetylsalicylic acid (ASA) was investigated at platinum electrode us... more Electroreduction behavior of acetylsalicylic acid (ASA) was investigated at platinum electrode using the cyclic voltammetry method. An effect of scan rate, ASA concentration and pH on electrode reaction was determined. The process is diffusion-controlled. Parameters of ASA electroreduction, i.e., rate constant, charge transfer coefficient and diffusion coefficient, were calculated. The ASA electroreduction is quasireversible and proceeds in two steps. This process is preceded by substrate hydrolysis resulting in the formation of salicylic (SA) and acetic (AA) acid. Hydrolysis products are electrochemically reduced. In the first and second step, electroreduction of SA and AA proceeds, respectively. Possible mechanism of ASA electroreduction was proposed.

Renata KASPRZAK-MAJAK, Jacek GÓRALSKI, Agnieszka RUPPERT

Voltammetric studies of acetylsalicylic acid electrooxidation at platinum electrode

Electrochimica Acta, 2013

ABSTRACT

Effect of MCM-41 on the physicochemical properties of Mo and NiMo catalysts and their performance in DBT conversion

Catalysis Today, 2006

The influence of mesoporous materials on the properties and HDS activity of Mo and NiMo catalysts... more The influence of mesoporous materials on the properties and HDS activity of Mo and NiMo catalysts was investigated for supports containing 50wt.% of MCM-41. A series of catalysts was characterized by different techniques (SBET, TPD-NH3, TPR, SEM, XPS) and tested in dibenzothiophene (DBT) conversion. On the surface of the catalysts containing mesoporous materials, agglomerations of the Mo oxo-species were observed.

Determination of homovanillic acid and vanillylmandelic acid in urine of autistic children by gas chromatography/mass spectrometry

Medical science monitor : international medical journal of experimental and clinical research, 2010

Studies suggest dopamine nervous systems are involved in the pathogenesis of autistic disorder. Q... more Studies suggest dopamine nervous systems are involved in the pathogenesis of autistic disorder. Quantification of urinary homovanillic acid (HVA) and vanillylmandelic acid (VMA) can be a very important tool in the study of disorders of dopamine metabolism in autistic children. The urine specimens were collected from 20 autistic children and 36 neurologically normal children. Urinary HVA and VMA were simultaneously analyzed by gas chromatography-mass spectrometry. The method involves extraction of HVA and VMA from urinary samples and derivatization to N,O-bis(trimethylsilyl)trifluoroacetamide derivatives. The detection limits are 0.15 microg/mL and 0.23 microg/mL for VMA and HVA, respectively. The levels of HVA and VMA were higher in the urine of autistic children (28.8+/-15.5 micromol/mmol creatinine and 22.2+/-13.0 micromol/mmol creatinine, respectively) compared with those of the generally healthy children (4.6+/-0.7 micromol/mmol creatinine for HVA and 3.8+/-0.6 micromol/mmol cre...

Badania reakcji reformingu metanu ditlenkiem węgla na katalizatorach Ni/La2O3 modyfikowanych wapniem

Kataliza w ochronie środowiska

Przemysl Chemiczny, 1998

Badanie właściwości fizykochemicznych fotokatalizatorów TiO2/SiO2 i 1%Pt/TiO2/SiO2 w reakcji redukcji CO2 w H2O do metanolu

Synthesis and properties of SiO2-TiO2 supported nickel catalysts

Catalysts, 2020

A goal of this work was to investigate the influence of the preparation procedure and activation ... more A goal of this work was to investigate the influence of the preparation procedure and activation conditions (reduction temperature and reducing medium: pure hydrogen (100% H2) or hydrogen-argon mixture (5% H2-95% Ar)) on the activity of Co-containing BEA zeolites in Fischer–Tropsch synthesis. Therefore, a series of CoBEA zeolites were obtained by a conventional wet impregnation (Co5.0AlBEA) and a two-step postsynthesis preparation procedure involving dealumination and impregnation steps (Co5.0SiBEA). Both types of zeolites were calcined in air at 500 °C for 3 h and then reduced at 500, 800 and 900 °C for 1 h in 100 % H2 and in 5% H2–95% Ar mixture flow. The obtained Red-C-Co5.0AlBEA and Red-C-Co5.0SiBEA catalysts with various physicochemical properties were tested in Fischer–Tropsch reaction. Among the studied catalysts, Red-C-Co5.0SiBEA reduced at 500 °C in pure hydrogen was the most active, presenting selectivity to liquid products of 91% containing mainly C7–C16 n-alkanes and iso...

Portugaliae Electrochimica Acta, 2022

Ethylenediamine (EDA), diethylenetriamine (DETA) and N,N,N',N'-tetrakis (2-hydroxypropyl) ethylen... more Ethylenediamine (EDA), diethylenetriamine (DETA) and N,N,N',N'-tetrakis (2-hydroxypropyl) ethylenediamine (THPrED) are used relatively often in galvanic processes. Tetra-substituted derivatives, such as N, N, N ', N'-tetrakis (2-hydroxyethyl) ethylenediamine, (THEtED) are quite biologically stable and hardly degradable. In recent years, much attention has been devoted to electrochemical oxidation, using anodes with a high over-potential of O2 evolution, such as the boron-doped diamond (BDD). DETA and THPrED electrochemical treatment using a BDD anode was herein studied. The degradation efficiency of the amines was evaluated under different current intensities and reaction times. To determine the products formed in the oxidation process, ion chromatography (IC) was used. A high decrease in the current between the first and the second CV scan indicated the polymer film formation on the BDD electrode surface. Hydroxyl radicals formed at a potential of about 2 V and higher caused further oxidation of the electrode reaction products. It was found that NH4 + , CH3-COOH, N2, EDA, CO2 and NO3-were formed in a short reaction time, and at low current intensity. The mineralization occurred during substrates electrolysis, due to rapid DETA and THPrED decomposition. After 180 min of reaction, αTOC and αN values for DETA were 94% and 18%, respectively. For THPrED, αTOC was 98.6% and αN was 43.6%. Therefore, the electrochemical approach was considered a very promising method in practical application for the treatment of wastewater containing amines.

Selective hydrogenation of a~00, b~00-unsaturated aldehydes in gas phase on Pt/Ga 2 O 3 catalysts

P023 Wpływ pary wodnej na aktywność detekcyjną czujników gazowych wykonanych z Pt-Sn/SnO 2

P.I-7: Zjawisko histerezy w procesie temperaturowo programowanego utleniania tlenku węgla

K-5 Selektywne utlenianie tlenku węgla w obecności wodoru na katalizatorach Pt/nośnik

Układ Pt-Sn/TiO 2 jako materiał do budowy rezystancyjnych czujników lambda. Związek pomiędzy własnościami adsorpcyjnymi a detekcyjnymi

An application of Pt-Sn/SnO 2 catalysts to the formation of semiconductor gas sensors

Effects of alumina-titania supports on the activity of NiMo catalysts

Studies in Surface Science and Catalysis, 1999

ABSTRACT

Radiation Physics and Chemistry, 2013

We determined the minimum hydrotrope concentration (MHC) for SCS. c We analyzed the SCS reactions... more We determined the minimum hydrotrope concentration (MHC) for SCS. c We analyzed the SCS reactions with oxidizing and reducing species. c The rate constants for the oxidation and reduction of SCS were given.

Catalytic and physicochemical properties of Pt/α-GeO2 systems in reaction of selective hydrogenation of α,β-unsaturated aldehydes in a gas phase

Kinetics and Catalysis, 2007

Hydrogenation of crotonaldehyde in a gas phase over Pt/α-GeO2 catalysts was investigated. The sys... more Hydrogenation of crotonaldehyde in a gas phase over Pt/α-GeO2 catalysts was investigated. The systems were characterized by BET, XRD, TPR, TEM, ToF-SIMS, and FTIR methods. The optimum pretreatment parameters were studied. The best catalytic performance shows the catalyst 5 wt % Pt/α-GeO2 (69% selectivity to crotyl alcohol at 200 μmol s−1 g Pt −1 activity and 10% conversion of crotonaldehyde).

Journal of Electroanalytical Chemistry, 2014

Electroreduction behavior of acetylsalicylic acid (ASA) was investigated at platinum electrode us... more Electroreduction behavior of acetylsalicylic acid (ASA) was investigated at platinum electrode using the cyclic voltammetry method. An effect of scan rate, ASA concentration and pH on electrode reaction was determined. The process is diffusion-controlled. Parameters of ASA electroreduction, i.e., rate constant, charge transfer coefficient and diffusion coefficient, were calculated. The ASA electroreduction is quasireversible and proceeds in two steps. This process is preceded by substrate hydrolysis resulting in the formation of salicylic (SA) and acetic (AA) acid. Hydrolysis products are electrochemically reduced. In the first and second step, electroreduction of SA and AA proceeds, respectively. Possible mechanism of ASA electroreduction was proposed.

Renata KASPRZAK-MAJAK, Jacek GÓRALSKI, Agnieszka RUPPERT

Voltammetric studies of acetylsalicylic acid electrooxidation at platinum electrode

Electrochimica Acta, 2013

ABSTRACT

Effect of MCM-41 on the physicochemical properties of Mo and NiMo catalysts and their performance in DBT conversion

Catalysis Today, 2006

The influence of mesoporous materials on the properties and HDS activity of Mo and NiMo catalysts... more The influence of mesoporous materials on the properties and HDS activity of Mo and NiMo catalysts was investigated for supports containing 50wt.% of MCM-41. A series of catalysts was characterized by different techniques (SBET, TPD-NH3, TPR, SEM, XPS) and tested in dibenzothiophene (DBT) conversion. On the surface of the catalysts containing mesoporous materials, agglomerations of the Mo oxo-species were observed.

Determination of homovanillic acid and vanillylmandelic acid in urine of autistic children by gas chromatography/mass spectrometry

Medical science monitor : international medical journal of experimental and clinical research, 2010

Studies suggest dopamine nervous systems are involved in the pathogenesis of autistic disorder. Q... more Studies suggest dopamine nervous systems are involved in the pathogenesis of autistic disorder. Quantification of urinary homovanillic acid (HVA) and vanillylmandelic acid (VMA) can be a very important tool in the study of disorders of dopamine metabolism in autistic children. The urine specimens were collected from 20 autistic children and 36 neurologically normal children. Urinary HVA and VMA were simultaneously analyzed by gas chromatography-mass spectrometry. The method involves extraction of HVA and VMA from urinary samples and derivatization to N,O-bis(trimethylsilyl)trifluoroacetamide derivatives. The detection limits are 0.15 microg/mL and 0.23 microg/mL for VMA and HVA, respectively. The levels of HVA and VMA were higher in the urine of autistic children (28.8+/-15.5 micromol/mmol creatinine and 22.2+/-13.0 micromol/mmol creatinine, respectively) compared with those of the generally healthy children (4.6+/-0.7 micromol/mmol creatinine for HVA and 3.8+/-0.6 micromol/mmol cre...

Badania reakcji reformingu metanu ditlenkiem węgla na katalizatorach Ni/La2O3 modyfikowanych wapniem

Kataliza w ochronie środowiska

Przemysl Chemiczny, 1998

Badanie właściwości fizykochemicznych fotokatalizatorów TiO2/SiO2 i 1%Pt/TiO2/SiO2 w reakcji redukcji CO2 w H2O do metanolu

Synthesis and properties of SiO2-TiO2 supported nickel catalysts

Catalysts, 2020

A goal of this work was to investigate the influence of the preparation procedure and activation ... more A goal of this work was to investigate the influence of the preparation procedure and activation conditions (reduction temperature and reducing medium: pure hydrogen (100% H2) or hydrogen-argon mixture (5% H2-95% Ar)) on the activity of Co-containing BEA zeolites in Fischer–Tropsch synthesis. Therefore, a series of CoBEA zeolites were obtained by a conventional wet impregnation (Co5.0AlBEA) and a two-step postsynthesis preparation procedure involving dealumination and impregnation steps (Co5.0SiBEA). Both types of zeolites were calcined in air at 500 °C for 3 h and then reduced at 500, 800 and 900 °C for 1 h in 100 % H2 and in 5% H2–95% Ar mixture flow. The obtained Red-C-Co5.0AlBEA and Red-C-Co5.0SiBEA catalysts with various physicochemical properties were tested in Fischer–Tropsch reaction. Among the studied catalysts, Red-C-Co5.0SiBEA reduced at 500 °C in pure hydrogen was the most active, presenting selectivity to liquid products of 91% containing mainly C7–C16 n-alkanes and iso...