H. Pignon et al., Treatment of complex aqueous solutions by the coupling of ultrafiltration and adsorption onto activated carbon cloth, ENV TECHNOL, 21(11), 2000, pp. 1261-1270
The aim of this work was to estimate the efficiency of coupling the process
es of ultrafiltration and adsorption onto an activated carbon cloth in orde
r to treat complex aqueous solutions containing both organic micropollutant
s and macromolecules. First, the effectiveness of each treatment process wa
s studied separately in batch reactors for microorganics, like phenol or at
razine, and macromolecules like humic substances. The activated carbon clot
h displayed higher adsorption capacities for microorganics than granular ac
tivated carbon, from 45 mg g(-1) for phenol up to 370 mg g(-1) for atrazine
, whereas they were not efficient at adsorbing humic substances. Conversely
, as many as 80% of these macromolecules were removed by an ultrafiltration
membrane with a 10 000 D molecular weight cut-off. Secondly, the coupling
was tested directly using a surface water with an initial total organic car
bon of 20 mg l(-1) and around 30 mg l(-1) of suspended solids. At first, ba
tch experiments showed that the ultrafiltration step increased the activate
d carbon cloth performance, and the comparison of several activated carbon
cloths of different properties showed that the total organic carbon removal
was dependent on the adsorbent pore-size distribution. Then, continuous fl
ow reactor experiments were carried out using the surface water loaded with
atrazine. A coagulation-flocculation step was tested as a pre-treatment. T
he specific adsorption of micropollutants onto the activated carbon cloth w
as displayed: the pre-treatment improved the permeate quality (lower values
of total organic carbon), whereas it had a negligible impact on atrazine a
dsorption.