Highly aromatic base oil and method for producing highly aromatic base oil
A method for producing a highly aromatic base oil of the present invention includes a step of hydrorefining a clarified oil to obtain a highly aromatic base oil having an aromatic content of 50% by mass or more determined by a column chromatography analysis method. The step of hydrorefining a clarified oil is preferably performed under conditions of a hydrogen pressure of 5.0 to 20.0 MPa, a temperature of 280 to 400° C., a hydrogen oil ratio of 300 to 750 NL/L, and a space velocity of 0.3 to 2.0 h −1 . According to the present invention, a highly aromatic base oil used for rubber processing, asphalt reclamation and the like, and a novel method for producing a highly aromatic base oil can be provided.
1. A method for producing a highly aromatic base oil comprising:
hydrorefining a clarified oil to obtain a hydrorefined oil; and
fractionation-treating and/or adsorption-treating the hydrorefined oil to obtain a highly aromatic base oil having
an aromatic content of 50% by mass or more determined by a column chromatography analysis method,
a content of benzo(a)pyrene of 1 ppm by mass or less, and
a total content of the following aromatic compounds 1) to 8):
1) benzo(a)pyrene,
2) benzo(e)pyrene,
3) benzo(a)anthracene,
4) chrysene,
5) benzo(b)fluoranthene,
6) benzo(j)fluoranthene,
7) benzo(k)fluoranthene, and
8) dibenzo(a,h)anthracene
of 10 ppm by mass or less;
wherein the highly aromatic base oil has a kinematic viscosity at 40° C. of 100 mm 2 /s or more.
2. The method for producing a highly aromatic base oil according to claim 1 , wherein the hydrorefining the clarified oil is performed under conditions of
a hydrogen pressure of 5.0 to 20.0 MPa,
a temperature of 280 to 400° C.,
a hydrogen oil ratio of 300 to 750 NL/L, and
a space velocity of 0.3 to 2.0h −1 .
3. A method for producing a mixed-base oil comprising:
hydrorefining a clarified oil to obtain a hydrorefined oil;
fractionation-treating and/or adsorption-treating the hydrorefined oil to obtain a highly aromatic base oil having
an aromatic content of 50% by mass or more determined by a column chromatography analysis method,
a content of benzo(a)pyrene of 1 ppm by mass or less, and
a total content of the following aromatic compounds 1) to 8):
1) benzo(a)pyrene,
2) benzo(e)pyrene,
3) benzo(a)anthracene,
4) chrysene,
5) benzo(b)fluoranthene,
6) benzo(j)fluoranthene,
7) benzo(k)fluoranthene, and
8) dibenzo(a,h)anthracene
of 10 ppm by mass or less;
wherein the highly aromatic base oil has a kinematic viscosity at 40° C. of 100 mm 2 /s or more; and
mixing the highly aromatic base oil and one or more base oils selected from a mineral oil and a synthetic oil other than the highly aromatic base oil to obtain a mixed-base oil having
an aromatic content of 50% by mass or more determined by a column chromatography analysis method,
an aniline point of 100° C. or less,
% C A of 20 to 80 according to ASTM D2140,
a pour point of +10° C. or less,
a glass-transition point of −30° C. to −60° C.,
a rate of aromatic carbon of 0.1 to 0.5,
a content of benzo(a)pyrene of 1 ppm by mass or less, and
a total content of the following aromatic compounds 1) to 8):
1) benzo(a)pyrene,
2) benzo(e)pyrene,
3) benzo(a)anthracene,
4) chrysene,
5) benzo(b)fluoranthene,
6) benzo(j)fluoranthene,
7) benzo(k)fluoranthene, and
8) dibenzo(a,h)anthracene
of 10 ppm by mass or less.
4. A highly aromatic base oil obtained by the producing method according to claim 1 , wherein
the highly aromatic base oil has
an aromatic content of 50% by mass or more determined by a column chromatography analysis method,
an aniline point of 60° C. or less,
% C A of 30 to 80 according to ASTM D2140,
a pour point of +10° C. or less,
a glass-transition point of −30° C. to −60° C., and
a rate of aromatic carbon of 0.1 to 0.7.
5. A mixed-base oil comprising the highly aromatic base oil according to claim 4 and one or more base oils selected from a mineral oil and a synthetic oil other than the highly aromatic base oil, wherein
the mixed-base oil has
an aromatic content of 50% by mass or more determined by a column chromatography analysis method,
an aniline point of 100° C. or less,
% C A of 20 to 80 according to ASTM D2140,
a pour point of +10° C. or less,
a glass-transition point of −30° C. to −60° C., and
a rate of aromatic carbon of 0.1 to 0.5.