Adsorption of nitrobenzene in waste water by hydrothermal synthesized attapulgite

Natural attapulgite was difficult to recycle for low compressive strength. To increase material strength, Attapulgite-based filter was treated by hydrothermal synthesizing. Microstructure, surface area and pore size were investigated by scanning electron microscopy (SEM), Brunauer-Emmett-Teller method (BET) and Barrett-Joiner-Halenda method(BJH). SEM images showed that the attapulgite nanorods formed consecutive space network. Their BET surface area was significantly increased, BJH average pore size was slightly decreased. Their compressive strength was obviously increased. The adsorption of nitrobenzene was in fast adsorption within 6h and reached equilibrium after 8h. The maximum adsorption capacity was 24 mg/g. The adsorption capacity was almost linearly increased with the increase of nitrobenzene concentration. The adsorption of aniline was best at pH 9 . In low concentration, the removal rate for nitrobenzene reached the maximum at 93% when the dosing quantity of filter was 51.3g/L. The results demonstrated that this filter is an effective adsorbent for the removal of nitrobenzene in water.