Hydrophilic interaction liquid chromatographic separation of urea, HMTA and their reaction products in sol-gel feed solution

Presence of urea-formaldehyde reaction products such as monomethylolurea, dimethylolurea, trimethylolurea in the preboiled HMTA-urea (BHU) solution can influence the characteristics of thorium and plutonium rich MOX microspheres. Studies were carried out to separate these compounds in BHU solution with an objective to explain its role in the sol-gel process. Hydrophilic interaction liquid chromatography (HILIC) was employed for the separation. Different chromatographic parameters were studied to arrive at the optimum conditions for separation. The compounds such as formaldehyde, urea, monomethylolurea, dimethylolurea and hexamethylenetetramine were separated using a mobile phase consisting of acetonitrile and acetate buffer of pH 6. (author)