Wettability Alteration of Sandstone by Chemical Treatments

Figure 3

Water droplets on the surface of the sandstone cores before and after treatment with FG40.

(a) Water (without chemical treatment, 𝜃=40^∘)

(b) Water (treated with 0.05% FG40, 𝜃=93^∘)

(c) Water (treated with 0.1% FG40, 𝜃=142^∘)

(d) Water (treated with 0.2% FG40, 𝜃=134^∘)

(e) Water (treated with 0.3% FG40, 𝜃=140^∘)

(f) Water (treated with 0.5% FG40, 𝜃=130^∘)