3. Manufacturing processes

Non-ionic surfactants are obtained by two main processes.

• Condensation

  Esterification is the most important method, but transesterification and, less commonly, amide formation and glucosydation are also used. These reactions, as shown in the diagram below, lead to the elimination of water, low-molar-weight alcohols or hydrochloric acid.

  Esterification of polyhydric alcohols

  $$\begin{array}{l}n\text{R}-\text{COOH}+{\text{R}}^{\prime }—{\left(\text{OH}\right)}_n\to {\left(\text{R}—\text{COO}\right)}_n—{\text{R}}^{\prime }+n{\text{H}}_2\text{O}\\ n\text{R}-{\text{COOR}}^{″}+{\text{R}}^{\prime }—{\left(\text{OH}\right)}_n\to {\left(\text{R}—\text{COO}\right)}_n—{\text{R}}^{\prime }+n{\text{R}}^{″}—\text{OH}\\ n\left(\text{R}-\text{COCl}\right)+{\text{R}}^{\prime }-{\left(\text{OH}\right)}_n\to {\left(\text{RCOO}\right)}_n—{\text{R}}^{\prime }+n\text{HCl}\end{array}$$