摘要 |
It has been found that producing dimer acid by carrying out the dimerization reaction with an initial starting pressure above atmospheric pressure, with the initial pressure being created by the use of an inert gas, produces lighter colored product as compared to conventional methods of producing dimer acid. The present invention is a process for making dimer acid by reacting unsaturated fatty acids in a reaction zone where the initial starting pressure of the reaction zone is above atmospheric pressure before initiating the oligomerization of the unsaturated acids, with this initial pressure being created by the use of an inert gas. The process consists of providing a mixture of unsaturated fatty acid and an effective amount of dimerization catalyst and other optional reactants in a reaction zone, removing air, pressurizing the reaction zone with an inert gas to a pressure above atmospheric and then carrying out the dimerization of the fatty acid. |