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The etherifi cation of glycerol and isoamylenes was performed using several macromolecular ion-exchange resins in order to fi nd the best catalyst which would provide the maximum conversion of glycerol and higher selectivities to ethers. Some different organic solvents (tert-amyl alcohol, 1,4-dioxane, acetonitrile, n-hexane, dichloromethane, diisopropylamine and dimethylformamide) were used in the etherifi cation of glycerol. Reactions were carried out in a batch autoclave reactor at 1.5 MPa in the temperature range from 25 to 100 °C for 24 h of contact time. It was found that resins with a greater pore volume and greater pore diameter showed a better performance in solventless reactions, but when employing solvents their polarity was responsible for the distinct results obtained in the conversion of glycerol: relative abundance and composition of the polar and non-polar phases in the fi nal reaction mixture. The solubilization of glycerol and isoamylenes in the reaction mixture seems to be the main factor in the progress of the reaction, which is refl ected in the different amount of ethers primarily obtained in the non-polar phase. tert-Amyl alcohol showed the best results in terms of conversion of glycerol due to the total miscibility of both reactants but it must be employed at temperatures below 50 °C in order to avoid its dehydration reaction that reduces the catalyst activity.

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