The present study confirmed there were 7 different factors
which affected the properties of the adsorbent through orthogonal
and single-factor experiments: particle size of sludge (0.074 mm,
0.1 mm, 0.2 mm, 0.45 mm, 1 mm); concentration of KOH solution
(1 mol/L, 3 mol/L, 5 mol/L, 7 mol/L, 10 mol/L)