Analysis of hydrocarbons in acids
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In alkylation, in addition to analyzing the concentration of the acid and the moisture content, if one wants to analyze the hydrocarbons present in the acid, how is that done? Is it by analyzing the acid concentration and moisture, and can what’s left be considered hydrocarbons? What methods are there for analyzing hydrocarbons in acids?
A similar question: in the sulfonation of aromatic compounds, how can we analyze the organic components that have not reacted? The surface of products diluted with water sometimes has an oily layer, but it’s not clear how to conduct a quantitative analysis of it
This post was last edited by qugd on 2017-11-7 09:21. For an alkylation unit in a refinery, it depends on whether the catalytic acid used for alkylation is sulfuric acid, hydrofluoric acid, or a solid superacid (this process may not be widely used in industry). If the sulfuric acid method is used, in addition to water, hydrocarbons will remain in the acid; however, there will also be a considerable amount of organic substances in the form of sulfates and sulfonic acids. In such cases, measuring only the hydrocarbon content may not provide very accurate results. If it is the hydrofluoric acid method, then after dilution with water, the other components in the acid should be water, hydrocarbons, and a small amount of other impurities. The details of the process for solid superacid catalysts are not particularly clear, and of course such catalysts are also difficult to separate.
What was said upstairs covers it pretty well. In the sulfuric acid method, oily substances do exist, similar to esters; however, no specific tests have been conducted on them. .