Apparatus and method for super critical fluid extraction

A pump for use in supercritical fluid extraction, comprising:

• a means for performing supercritical fluid extraction;
• said pump having a piston means, and an inlet adapted to be connected to a source of supercritical fluid and an outlet adapted to be connected to said means for performing supercritical fluid extraction;
• a pump chamber within said pump communicating with said source of supercritical fluid and said means for supplying supercritical fluid to said means for performing supercritical fluid extraction;
• said piston means being adapted for drawing supercritical fluid into said pump chamber and forcing said supercritical fluid from said pump chamber;
• a seal having one side in contact with said supercritical fluid for blocking a flow of fluid past said piston means;
• a support means for supporting said piston means within said pump;
• said support means located on the one side of said seal in contact with said supercritical fluid;
• support means being comprised in means for supporting and aligning said piston means don each of both sides of said seal, whereby said piston means is maintained in alignment as it reciprocates.