Glycerol is a by-product from biodiesel and soap industries. The principal by-product of biodiesel production is the crude glycerol, which is about 10 %wt of vegetable oil. Glycerol is the inevitable by-product of the transesterification process. The recovery of high quality glycerol as a biodiesel by-product is the primary option to be considered to lower the cost of biodiesel. Direct addition of glycerol to the fuel is not possible; however, derivatives of glycerol such as ethers have potential for use as additives with biodiesel, diesel, or biodiesel-diesel blends. Glycerol can be converted into commercially-valued oxygenate products used for the diesel fuel blends. Glycerol alkyl ethers are easily synthesized using glycerol, which reacts with isobutylene in the presence of an acid catalyst. Etherification of glycerol with isobutylene can be effectively accomplished using Amberlyst-15 as a catalyst under a variety of reaction conditions. The ethers of glycerol can be effectively added to biodiesel fuels, providing a 5 K reduction in cloud point and an 8% reduction in viscosity.