Aspects of refining biodiesel byproduct glycerin

The article addresses aspects of refining on the ground of colloid chemical principles. Chemical andphysical operations have been employed with the aim of producing refined grade glycerine withoutthe use of high vacuum distillation. In glycerine refining sequences neutralization, decanting,esterification, atmospheric distillation and adsorption have been employed. Acid-base titration andrheology tests formed the basis for colloid chemical characterization of glycerine byproduct and itsintermediates in the refining procedures. It has been visualized in titration curve that inneutralization of the byproduct there are two levels of reactions: acid-base neutralization in therange of pH=9-11 and a hydrolysis in the range of pH=3-5. Rheology measurements indicated thatglycerine byproduct and its intermediates are dispersions that resemble specifics of solid particlestabilized (Pickering) emulsions. A simple spectroscopic method is recommended for quick check ofrefining efficiency.