Production of low cost and effective porous adsorbent from Iranian kaolin by sonication for recovery of wastewater contaminated by cationic dye

The discharge of industrial wastewaters contaminated by cationic dyes caused to serious environmental problem for soil, surface and ground water. The present study was aimed to produce low cost porous adsorbent from Iranian kaolins which contains high level of quartz. In the first step, the two processed kaolins were mixed with different content of sodium hydroxide and treated by heating at 700 C. Secondly, the obtained materials was quenched into the water to prepared porous adsorbents with sonication. The removal efficiency of produced adsorbents is fundamentally depends on raw material composition and sodium hydroxide content. The presence of illite and pyrophillite in kaolin cause to decrease the sodium hydroxide content and achieve an appropriate amorphous adsorbent whilst, the ultrasound- assisted technique should be applied to provide a suitable adsorbent when the kaolinite is the predominant phase in clay. Moreover, the alkali ratio should be increased to 2.3. The employed technique can be easily applied to produce an effective adsorbent for removal of cationic dye from textile wastewaters.