Abstract: Methods and systems for measuring component concentrations. The methods may include providing a system configured for contacting a first component, a second component, and a third component; determining a concentration of the second component in a reactor; determining a concentration of the third component in the reactor; determining a temperature and a pressure of a first apparatus downstream of the reactor; and calculating a first concentration of the first component in the reactor based on (i) the concentration of the second component in the reactor, (ii) the concentration of the third component in the reactor, and (iii) the temperature and the pressure of the first apparatus.

Abstract: A system and method for removing acetaldehyde from an acetic acid system are disclosed. The method includes, providing a light-ends stream, comprising carbon monoxide, carbon dioxide, acetaldehyde, methyl iodide, methyl acetate, water, acetic acid, or mixtures thereof; condensing the light-ends stream to form one or more liquid phase compositions and a vapor phase composition, comprising a majority of the carbon monoxide and carbon dioxide and a minor portion of the acetaldehyde, methyl iodide, water, and acetic acid; contacting the vapor phase composition with a solvent to produce a liquid stream, comprising methyl iodide, acetaldehyde, and a portion of the solvent; and contacting the liquid stream, and optionally a polyol compound, with an acid catalyst to convert a portion of the acetaldehyde to an aldehyde derivative having a higher boiling point than acetaldehyde.

Abstract: A system and method for removing acetaldehyde from an acetic acid system, including providing a solution from the acetic acid system, the stream having methyl iodide and acetaldehyde, distilling the solution to produce an overhead stream having a higher concentration of acetaldehyde, contacting the overhead stream, and optionally a hydroxyl compound, with an acid catalyst to convert the acetaldehyde to an aldehyde derivative having a higher boiling point than acetaldehyde.