Question
Chemistry Explained: Formaldehyde
Summary
Explanation of the reactions and methods for the parameter Formaldehyde.
Answer
Introduction:
Formaldehyde is used in the treatment of fabric in textile industries, in metal plating baths, as apreservative for biological tissues and as a disinfectant in dialysis and reverse osmosis equipment.The MBTH Method is a sensitive colorimetric test for low range measurement of aldehydes; it ismost sensitive for formaldehyde.
Chemical Reactions:
MBTH Method
MBTH (3-methyl-2-benzothiazoline hydrazone) is added in excess to a sample containingformaldehyde, triggering multiple reactions. First, MBTH and formaldehyde react to form an azine(1). Excess MBTH is oxidized by addition of a developing solution (2). Oxidized MBTH reacts withthe azine to form a species with an intense blue color (3). Intensity of the blue color is proportionalto the original concentration of formaldehyde.MBTH is contained in MBTH Powder Pillows. Liquid reagent for oxidizing excess MBTH iscontained in the Developing Solution for Low Range Formaldehyde.

This information is from the document Formaldehyde for Water