Method of producing a fuel additive

A method of producing a fuel additive, comprising:

• passing a feed stream comprising hydrocarbons through a cracker unit producing a cracked stream;
• passing the cracked stream through a methyl tertiary butyl ether unit to produce a first process stream, wherein methanol and isobutylene are present in the methyl tertiary butyl ether unit in a molar ratio of one mole of isobutylene to 0.1 mole to 5 moles of methanol;
• withdrawing a methyl tertiary butyl ether product from the methyl tertiary butyl ether unit;
• passing the first process stream through a selective butadiene hydrogenation unit to produce a second process stream;
• passing the second process stream through a hydration unit producing a third process steam, wherein a temperature within the hydration unit is 30° C. to 190° C., a pressure within the hydration unit is 500 kiloPascals to 20,000 kiloPascals, and wherein greater than or equal to 0.1090% of any butene present in the second process stream is converted to butanol within the hydration unit;
• withdrawing a fuel additive product from the hydration unit, wherein the fuel additive product comprises at least one of 1-butanol, 2-butanol, tert-butyl alcohol, or a C4 dimer;
• passing the third process stream through a total hydrogenation unit producing a hydrogenated process stream;
• and
• recycling the hydrogenated process stream to a cracker unit.