Characteristics

Crude oil

Sand filtered oil

Yellowing index

86.33^a ± 0.0067

86.12^a ± 0.26

Brown index

187.39^a ± 0.77

183.51^a ± 3.0067

Clarity

95.25^a ± 0.045

95.15^a ± 0.043

Turbidity (NTU)

14.61^a ± 0.24

0.99^b,c ± 0.43