Controlling the size of SBA-15 can be beneficial for exploiting CMK-3, whichhas excellent structural parameters, for better performance in adsorption and/orcatalytic processes. In this study, the width of freestanding SBA-15 rods wasreadily and successfully regulated by simply altering the stirring power duringthe synthesis. A higher stirring rate produced SBA-15 rods with larger width.Then, the size of the CMK-3 rods was adjusted by duplication of the differentsizedSBA-15. The results show that the larger sized CMK-3 has higher specificsurface area and pore volume, which led to a higher adsorption capacity and afaster adsorption rate. It is believed that the synthetic method reported here ispowerful for developing better mesoporous carbon for application in waterpurification and catalysis.