Production of Monomeric Aromatic Compounds from Oil Palm Empty Fruit Bunch Fiber Lignin by Chemical and Enzymatic Methods

Figure 2

Effects of sodium hydroxide’s concentration and time on the yields of (a) hydroxybenzoic acid, (b) p-hydroxybenzaldehyde, (c) vanillic acid, (d) vanillin, (e) syringic acid, (f) syringaldehyde, (g) p-coumaric acid, and (h) ferulic acid during oxygen oxidation at 100°C.

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)