To obtain a dewaxing auxiliary, having an effect on a light or heavy wax hydrocarbon oil in a self-cooling type dewaxing method using a lower hydrocarbon solvent, capable of dewaxing without using an alkyl naphthalene condensate or a vinyl acetate copolymer having problems of a chlorine compound or a low-molecular acid.
This dewaxing auxiliary is a mixture of a polyalkyl methacrylate (1) having a 10-20C alkyl chain length at the side chain and 10,000-800,000 weight-average molecular weight and a polyalkyl acrylate (2) having a 16-30C alkyl chain length at the side chain and 10,000-800,000 weight- average molecular weight in the mass ratio of (1) to (2) of (1):(2) of 9:1-100:1. The amount of the dewaxing auxiliary added is 0.001-1.00 mass % based on a wax-containing hydrocarbon oil.
MATSUI YUICHI
HIRAIDE AKIYUKI
