a short path distillation unit 5 the short path distillation unit 5 may be an american verfahrens technische anlagen avta gmbh unit with a 0 4 m 2 stainless steel heating surface with hot oil heating and a stainless steel condenser chilled with glycol in certain embodiments the hot oil temperature is kept at 128 u00b0 c and absolute system pressure at 0 25 mmhg the feed rate may be between about 52 5 lb hr m 2 and 212 5 lb hr m 2 respectively 23 81 and 96 39 kg hr m 2 the distillate take off can be about 8 to 10 for orange oil but depends on the raw material composition from the short path distillation unit 5 there is obtained a high ar distillate and a low ar residue the high ar distillate is passed along line 6 to a second batch distillation unit 8 and the low ar residue is passed along line 7 to the final holding tank 10 the second batch distillation unit 8 may be the same as distillation unit 2 by way of example the distillation may be started at about 110 u00b0 c and absolute pressure of about 1 mm hg to about 10 mm hg the distillation continues by gradually increasing the pot temperature to at least about 150 u00b0 c and decreasing the system absolute pressure of 1 mmhg from this is obtained a low ar redistilled distillate which is conveyed along line 9 to the final holding.