Reported Procedure :
Analytical reagent- or HPLC-grade solvents were obtained from commercial sources and used as is or were dried using the various methods described herein. Desiccants (3 A ° molecular sieves, various silicas, neutral alumina) were obtained from commercial suppliers and were predried at 300 C for 24 h immediately before use. Solvents were dried either by allowing them to stand over the desiccant under nitrogen or by passing the solvent over a column of the desiccant as specified, inside the glove box..
Reference : Drying of Organic Solvents : Quantitative Evaluation of the Efficiency of Several Dessicants-
William , G. B. D.; Lawton , M. J. Org. Chem. 2010, ASAP.