Scriabin had at least three major periods: Early, Middle, and Late.
Here's a more detailed, although rough and imperfect, breakdown:
Juvenilia (Romantic). Includes the G# and Eb minor sonatas, and many short pieces.
Early Romantic. Op. 6 to Op. 14. (Op. 2 No. 1 fits here, too.)
Mid Romantic. Op. 15 to Op. 21.
Late Romantic. Op. 22 to Op. 28.
Impressionism/sensuality. Op. 30 to Op. 33 No. 2.
Impetuosity, introspection, increasing abstraction. Op. 33 Nos. 3 and 4 to Op. 45.
Ecstasy (energetic abstraction). Op. 48 to Op. 56.
Introspection, sensuality. Op. 57 to 58.
Impure spirits. Op. 59 to 63.
Purifying light. Op. 64 to Op. 65.
Labyrinth. Op. 66.
Evil. Op. 67 to Op. 69.
Infinity. Op. 70 to Op. 71.
Apocalypse. Op. 72 to Op. 73.
Post apocalypse. Op. 74.
(Op. 60 is difficult to classify. It falls well within the late period, however.)