Meso-architectured siliceous hollow quasi-capsule.

Reactive dyes have been identified to be highly hazardous pollutants because they were shown to be more toxic towards mammals than general organic compounds and organic dyes. Accordingly, for the first time, meso-architectured mercapto-modified siliceous hollow quasi-capsules (SH-SHQC) were prepared by a facile, ultrasonic-assisted, and one-step synthesis protocol. Adsorptive removal of rhodamine B (RhB) and methylene blue (MB) onto SH-SHQC in a batch system has been investigated. Isotherm results agreed very well with the Langmuir equation for both dyes. The maximum adsorption capacity of SH-SHQC for RhB and MB was determined with the Langmuir equation and was found to be 147.06 and 119.05 mg g at 298 K, respectively (pH: 6.0 for RhB and 7.0 for MB; adsorbent dosage: 15.0 mg; the volume of the dye solution: 40.0 mL). Among different kinetic models, the pseudo-first-order equation was better fitted since experimental data agreed very well with theoretical data. SH-SHQC was shown to be a promising adsorbent for adsorptive removal of reactive dyes from aqueous solutions. To date, there has been no report on the adsorption of reactive dye cations by meso-architectured mercapto-modified siliceous hollow quasi-capsules prepared by an ultrasonic-assisted, one-pot, and sol-gel synthesis method.