Abstract: Devices, systems and methods for the preparation of an oxygenate compound or mixture of oxygenate compounds suitable for use in internal combustion engines are disclosed. An internal combustion engine system includes: a fuel system including an oxygenate compound synthesis device including a reactor including a catalyst, the oxygenate compound synthesis device being configured to convert at least a portion of a feedstock to an oxygenate compound or a mixture of oxygenate compounds; and an internal combustion engine configured to initiate combustion through compression or high energy discharge, the internal combustion engine including: a fuel injection system configured to provide fuel injection, and a cooling system configured to cool the internal combustion engine, the internal combustion engine being configured to heat the oxygenate compound synthesis device using heat from the cooling system of the internal combustion engine. Applications of the devices, systems and methods are also disclosed.