USE OF A LIQUID CHEMICAL WASTE TO PRODUCE A CLAY-CARBON ADSORBENT

The feasibility of producing an adsorbent from an alkaline aqueous tar ry industrial waste has been investigated in this study. The inherent disadvantages of producing a solid carbonaceous material from a waste with its organic content in a dissolved state were overcome by neutral ising the waste liquor to pH < 2 in the presence of fuller's earth, fi ltering and producing a solid cake more suitable for thermal treatment . Optimisation of this procedure, followed by ZnCl2 activation, produc ed clay-carbon adsorbents with surface areas of up to 225 m(2) g(-1) c apable of adsorbing 28% of phenol and 35% of 4-nitrophenol from 10 mM aqueous solution. The potential of this procedure in a beneficial wast e reduction and re-use context are highlighted. (C) 1998 SCI.