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Application of non-membrane electrolytic cell for electrochemical volatile species generation of transition metals
Kobrlová, Andrea ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
This diploma thesis is focused on the study of electrochemical generation volatile species of gold and silver. Two non-membrane electrolytic cells were constructed for electrochemical generation volatile species. These cells differ in the volume of electrode chamber. An atomic absorption spectrometry with quartz tube atomizer was used in most experiments. The equipment was performed in flow continuous mode. Experiments confirmed, that it is possible to use an atomic absorption spectrometry with quartz tube atomizer for generate volatile species of gold and silver by using two non-membrane electrolytic cells. The main part of this thesis was to find optimal conditions for the electrochemical generation of volatile species of gold and silver. These optimized parameters were: the cathode material, the type of electrolyte, the flow rate of the carrier gas, the generation current and the electrolyte flow rate. The calibration curves for both analytes were measured for both non-membrane electrolytic cells and the basic characteristics of the measurement were observed. Detection limit for electrochemical generation of gold was 1,61mg dm 3 and repeatability 3,93 %, detection limit for electrochemical generation of silver was 0,20 mg dm 3 and repeatability 7,33 %. Thanks to the experiments with a...
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Speciation analysis of arsenic and mercury using postcolumn generation of their volatile compounds for needs of atomic spectroscopic methods
Linhart, Ondřej
The presented dissertation thesis deals with the use of UV-photochemical generation of volatile compounds (UV-PVG) as a derivatization technique for the combination of high-performance liquid chromatography (HPLC) and atomic absorption spectrometry (AAS) detection. Two model elements arsenic and mercury and their compounds were selected for the speciation analysis. The work was divided into several parts that follow. In the first part of the research, the apparatus for the UV-photochemical generation of the volatile mercury compounds and their detection with a new continuum source and high-resolution atomic absorption spectrometer (HR-CS AAS) with an externally heated detection tube was constructed. The analytical method was adapted for use with atomic fluorescence detection with the aim to improve sensitivity of the determination. Furthermore, apparatus for the electrochemical generation of cold mercury vapor with AAS detection was built. The construction of the apparatus was followed by optimization of the reaction conditions (concentration and flow of electrochemical reagents: sulfuric and hydrochloric acid, mobile phase, carrier medium, flow rate of the carrier gas and localization of its introduction), determination of the analytical figures of merit, and comparation of the methods. Both...
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UV-photochemical generation of volatile selenium compounds for ultratrace analysis by AAS
Rybínová, Marcela
This thesis deals with the study of UV-photochemical generation of volatile compounds (UV-PVG) in connection with atomic absorption spectrometry (AAS). Selenium (Se(IV)) was selected as a model analyte and many experiments were carried out to expand the current sum of knowledge of the topic. The study was commenced by assembling the UV-PVG apparatus in the continuous flow mode. The detection method used was AAS with externally heated quartz furnace atomizer. The focus of the first step of the study was on the construction of the volatile compounds generator (UV-photoreactor) with emphasis on the material used; tubes made of teflon or quartz of different diameters were tested. The construction of the apparatus was followed by optimization of the reaction conditions (the type and concentration of the photochemical agent and other agents, which increase the analytical signal; the carrier gas and the auxiliary hydrogen gas flow rate; the sample flow rate). Eventually, the analytical figures of merit of the selenium determination using the proposed method were found. The results showed that teflon reaction tubes are a good competitor to those made of quartz. The accuracy of the method has been successfully verified by analysis of certified reference material and its applicability has been further tested...
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Speciation analysis of arsenic and mercury using postcolumn generation of their volatile compounds for needs of atomic spectroscopic methods
Linhart, Ondřej
The presented dissertation thesis deals with the use of UV-photochemical generation of volatile compounds (UV-PVG) as a derivatization technique for the combination of high-performance liquid chromatography (HPLC) and atomic absorption spectrometry (AAS) detection. Two model elements arsenic and mercury and their compounds were selected for the speciation analysis. The work was divided into several parts that follow. In the first part of the research, the apparatus for the UV-photochemical generation of the volatile mercury compounds and their detection with a new continuum source and high-resolution atomic absorption spectrometer (HR-CS AAS) with an externally heated detection tube was constructed. The analytical method was adapted for use with atomic fluorescence detection with the aim to improve sensitivity of the determination. Furthermore, apparatus for the electrochemical generation of cold mercury vapor with AAS detection was built. The construction of the apparatus was followed by optimization of the reaction conditions (concentration and flow of electrochemical reagents: sulfuric and hydrochloric acid, mobile phase, carrier medium, flow rate of the carrier gas and localization of its introduction), determination of the analytical figures of merit, and comparation of the methods. Both...
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Speciation analysis of arsenic and mercury using postcolumn generation of their volatile compounds for needs of atomic spectroscopic methods
Linhart, Ondřej ; Červený, Václav (advisor) ; Spěváčková, Věra (referee) ; Šíma, Jan (referee)
The presented dissertation thesis deals with the use of UV-photochemical generation of volatile compounds (UV-PVG) as a derivatization technique for the combination of high-performance liquid chromatography (HPLC) and atomic absorption spectrometry (AAS) detection. Two model elements arsenic and mercury and their compounds were selected for the speciation analysis. The work was divided into several parts that follow. In the first part of the research, the apparatus for the UV-photochemical generation of the volatile mercury compounds and their detection with a new continuum source and high-resolution atomic absorption spectrometer (HR-CS AAS) with an externally heated detection tube was constructed. The analytical method was adapted for use with atomic fluorescence detection with the aim to improve sensitivity of the determination. Furthermore, apparatus for the electrochemical generation of cold mercury vapor with AAS detection was built. The construction of the apparatus was followed by optimization of the reaction conditions (concentration and flow of electrochemical reagents: sulfuric and hydrochloric acid, mobile phase, carrier medium, flow rate of the carrier gas and localization of its introduction), determination of the analytical figures of merit, and comparation of the methods. Both...
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UV-photochemical generation of volatile selenium compounds for ultratrace analysis by AAS
Rybínová, Marcela ; Rychlovský, Petr (advisor) ; Komárek, Josef (referee) ; Šíma, Jan (referee)
This thesis deals with the study of UV-photochemical generation of volatile compounds (UV-PVG) in connection with atomic absorption spectrometry (AAS). Selenium (Se(IV)) was selected as a model analyte and many experiments were carried out to expand the current sum of knowledge of the topic. The study was commenced by assembling the UV-PVG apparatus in the continuous flow mode. The detection method used was AAS with externally heated quartz furnace atomizer. The focus of the first step of the study was on the construction of the volatile compounds generator (UV-photoreactor) with emphasis on the material used; tubes made of teflon or quartz of different diameters were tested. The construction of the apparatus was followed by optimization of the reaction conditions (the type and concentration of the photochemical agent and other agents, which increase the analytical signal; the carrier gas and the auxiliary hydrogen gas flow rate; the sample flow rate). Eventually, the analytical figures of merit of the selenium determination using the proposed method were found. The results showed that teflon reaction tubes are a good competitor to those made of quartz. The accuracy of the method has been successfully verified by analysis of certified reference material and its applicability has been further tested...
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UV-photochemical generation of volatile selenium compounds for ultratrace analysis by AAS
Rybínová, Marcela
This thesis deals with the study of UV-photochemical generation of volatile compounds (UV-PVG) in connection with atomic absorption spectrometry (AAS). Selenium (Se(IV)) was selected as a model analyte and many experiments were carried out to expand the current sum of knowledge of the topic. The study was commenced by assembling the UV-PVG apparatus in the continuous flow mode. The detection method used was AAS with externally heated quartz furnace atomizer. The focus of the first step of the study was on the construction of the volatile compounds generator (UV-photoreactor) with emphasis on the material used; tubes made of teflon or quartz of different diameters were tested. The construction of the apparatus was followed by optimization of the reaction conditions (the type and concentration of the photochemical agent and other agents, which increase the analytical signal; the carrier gas and the auxiliary hydrogen gas flow rate; the sample flow rate). Eventually, the analytical figures of merit of the selenium determination using the proposed method were found. The results showed that teflon reaction tubes are a good competitor to those made of quartz. The accuracy of the method has been successfully verified by analysis of certified reference material and its applicability has been further tested...
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Application of non-membrane electrolytic cell for electrochemical volatile species generation of transition metals
Kobrlová, Andrea ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
This diploma thesis is focused on the study of electrochemical generation volatile species of gold and silver. Two non-membrane electrolytic cells were constructed for electrochemical generation volatile species. These cells differ in the volume of electrode chamber. An atomic absorption spectrometry with quartz tube atomizer was used in most experiments. The equipment was performed in flow continuous mode. Experiments confirmed, that it is possible to use an atomic absorption spectrometry with quartz tube atomizer for generate volatile species of gold and silver by using two non-membrane electrolytic cells. The main part of this thesis was to find optimal conditions for the electrochemical generation of volatile species of gold and silver. These optimized parameters were: the cathode material, the type of electrolyte, the flow rate of the carrier gas, the generation current and the electrolyte flow rate. The calibration curves for both analytes were measured for both non-membrane electrolytic cells and the basic characteristics of the measurement were observed. Detection limit for electrochemical generation of gold was 1,61mg dm 3 and repeatability 3,93 %, detection limit for electrochemical generation of silver was 0,20 mg dm 3 and repeatability 7,33 %. Thanks to the experiments with a...
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