The present disclosure provides a feed injector for a gasification system. The feed injector may include an inner tube defining an inner feed passage therein, an intermediate tube defining an intermediate feed passage therein, and an outer tube defining an outer feed passage therein. The outer tube may include an outer tube pipe portion and an outer tube tip portion attached to one another, and the outer tube tip portion may be formed of a ceramic matrix composite, a sintered Silicon Carbide, or a sintered Silicon Nitride. The present disclosure also provides a related method of operating a feed injector of a gasification system as well as a related integrated gasification combined cycle power plant.