Ionic liquids and cellulose ester compositions and processes for producing ionic liquids and cellulose esters. Cellulose esters can be produced by esterifying cellulose in a reaction medium comprising one or more halide ionic liquids and at least one binary component. Cellulose esters prepared via the methods of the present invention can have a degree of substitution (“DS”) of at least 1.5 and can comprise a plurality of ester substituents, where at least 50 percent of the ester substituents comprise alkyl esters having a carbon chain length of at least 6 carbons.