The question is whether the sulfur analysis in Coulomb refers to total sulfur or organic sulfur
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I believe that Coulombic sulfur analysis measures the total amount of sulfur present in a gas. However, one of my predecessors said that Coulombic sulfur analysis detects organic sulfur in samples, not the total sulfur. Hydrogen sulfide, carbonyl sulfide, and sulfur dioxide in gases are all inorganic sulfur compounds. When using Coulombic analysis, according to its principle, these compounds are converted into sulfur dioxide and sulfur trioxide under combustion in a tube at 800 degrees Celsius; they then react with the electrolyte. Isn’t this inorganic sulfur? She said that fluorescence sulfur analysis is the one that measures the total amount of sulfur. What do you all think? I think for liquids it’s also total sulfur
Total sulfur should include organic sulfur and inorganic sulfur. Although the Coulomb method involves decomposing the sample by combustion, the sample decomposition process is essentially an oxidation process in which low-valent sulfur is oxidized to higher-valent states of sulfur, that is, to sulfur dioxide. However, for some high-valent sulfides, such as sulfates, sulfonates, or their esters, during the oxidative decomposition process, the oxides are mainly sulfur trioxide; whereas the coulometric detector measures sulfur dioxide using the iodimetric method, so these high-valent sulfur compounds cannot be accurately determined. Fluorescent sulfur analysis is also divided into two categories: tube furnace combustion-UV fluorescence method, which is ineffective for sulfur in higher oxidation states (or rather, the measurement quality is not good). X-ray fluorescence spectroscopy is the method for determining total sulfur because it only acts on sulfur atoms. Any method has its advantages as well as its limitations. By understanding the principles of the method and the chemical processes involved, one can grasp its advantages and limitations.
It is generally believed that the Coulomb method for determining sulfur in gases measures the total flow
Although Coulomb analysis is used to analyze sulfur dioxide, there is a reversible reaction between sulfur dioxide and sulfur trioxide, with an equilibrium constant. Therefore, sulfur dioxide multiplied by a constant can also be used to calculate the total sulfur content. :)