A method of producing a fuel additive includes passing a feed stream comprising C4 hydrocarbons through a methyl tertiary butyl ether unit producing a first process stream; passing the first process stream through a selective butadiene hydrogenation unit transforming greater than or equal to 90% by weight of the butadiene to 1-butene and 2-butene, preferably greater than or equal to 93%, preferably, greater than or equal to 94%, more preferably, greater than or equal to 95% producing a second process stream; passing the second process stream through a hydration unit producing a third process stream and the fuel additive; passing the third process stream through a total hydrogenation unit producing a hydrogenated stream; and passing the hydrogenated stream to a cracker unit.