The diffusivity of nitrogen in liquid cyclohexane has been measured at temperatures from 21 °C to 140 °C and at pressures of 10 - 15 atm, using a high pressure wetted sphere absorber apparatus. The diffusivity increased from 4.0 × 10-5 cm2 s-1 to 2.8 × 10-4 cm2 s-1 over this temperature range. Rippling of the film at the higher flow rates restricted the flow rate range which could be utilized for the diffusivity determinations. The measured absorption rates for flows in which rippling occurred were up to 15% higher on a 20 mm sphere and up to 40% higher on a 30 mm sphere. This limited the suitability of the wetted sphere absorber for this type of work.