Patent ID: 7252753

Claim:
A process for producing a dielectric fluid comprising: a) providing a highly paraffinic wax; b) hydroisomerizing the highly paraffinic wax using a shape selective intermediate pore size molecular sieve comprising a noble metal hydrogenation component under conditions of about 600° F. to about 750° F. to provide an isomerized oil; and c) fractionating the isomerized oil to provide at least one oil fraction having a T 90 boiling point ≧950° F., a kinematic viscosity between about 6 cSt and about 20 cSt at 100° C., and a pour point of ≧−14° C., wherein the oil comprises ≧10 weight % molecules with monocycloparaffinic functionality, ≦3 weight % molecules with multicycloparaffinic functionality, and less than 0.30 weight % aromatics d) optionally blending the oil fraction with an effective amount of one or more additives; and e) isolating a dielectric fluid having a dielectric breakdown of ≧25 kV as measured by ASTM D877.