Patent ID: 7767837

Claim:
A method comprising: contacting an alcohol, a feed comprising one or more glycerides, water and equal to or greater than 2 wt % of one or more free fatty acids, and a solid acid catalyst in one or more reactors; and recovering from the one or more reactors an effluent comprising equal to or greater than about 75 wt % alkyl ester and equal to or less than about 5 wt % glyceride wherein the reaction in the one or more reactors is carried out at a temperature ranging from 100° C. to 220° C. and a pressure to maintain the reaction components in the liquid state, wherein the solid acid catalyst is sulfated zirconia and the sulfated zirconia catalyst is present in the one or more reactors in an amount of from about 100 to about 3000 g/liter of internal reactor volume and wherein water is present in the feed in an amount from about 1% to equal to or less than about 8% by mass.