TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: Distilling the water-containing biomass-derived pyrolysis oil comprises selecting the azeotrope-forming liquid comprising toluene, ethanol, acetone, 2-propanol, cyclohexane, 2-butanone, octane, benzene, or ethyl acetate. Distilling the water-containing biomass-derived pyrolysis oil comprises forming the azeotrope comprising ethanol/water, toluene/water, acetone/water, 2 -propanol/water, cyclohexane/water, 2 -butanone/water, octane/water, ethanol/toluene/water, 1-butanol/octane/water, benzene/2-propanol/water, ethanol/2-butanone/water, or ethanol/ethyl acetate/water. Distilling the water-containing biomass-derived pyrolysis oil comprises heating the water-containing biomass-derived pyrolysis oil to a minimum distillation temperature of the boiling point of the azeotrope at a given atmospheric pressure. Distilling the water-containing biomass-derived pyrolysis oil comprises adding the azeotrope-forming liquid to the water-containing biomass-derived pyrolysis oil, a minimum amount of the azeotrope-forming liquid to be added (kg) calculated by dividing the difference of weight ratio of azeotrope-forming liquid to water in azeotrope mass (kg) water to be removed from biomass-derived pyrolysis oil with minimum amount of azeotrope-forming liquid to be added (kg) to the starting oil, where the mass (kg) of water to be removed is equal to the product of mass of water-containing biomass-derived pyrolysis oil (kg) and the quotient of the difference of water concentration in grams of water per gram of oil of the initial (water-containing biomass-derived pyrolysis oil) and final pyrolysis oil (low water biomass-derived pyrolysis oil) with difference of 1 and final pyrolysis oil (low water biomass-derived pyrolysis oil). Distilling the water-containing biomass-derived pyrolysis oil further comprises adding more of the azeotrope-forming liquid to the water-containing biomass-derived pyrolysis oil than the minimum amount. Distilling the water-containing biomass-derived pyrolysis oil in the presence of an azeotrope-forming liquid comprises distilling the water-containing biomass-derived pyrolysis oil in the presence of a first azeotrope-forming liquid and a second azeotrope-forming liquid.