A new solventless process to hydrophobize silica powders in fluidized beds

摘要: A new hydrophiztaion technique was developed in a fluidized bed reactor to modify the surface of silica-based powders with n-octadecyltrichlorosilane (ODTCS). The reaction performed at dry phase by mixing two classes particles during fluidization: “target-particles” be treated (a fine microporous silica powder) and “ODTCS-carrier” consisting coarser porous alumina beads containing an adequate amount reagent. results showed that ODTCS successfully anchored on achieved high coverage (1.4 groups/nm2) only few minutes interesting hydrophobic behavior. energy consumption is reduced if carried out low temperatures, but using humidified air (7% RH). These conditions promote, however, vertical polymerization reagent solids surface. © 2008 American Institute Chemical Engineers AIChE J,