Porous ceramic articles may be produced by using a gas as a pore former, where the gas is injected into a ceramic precursor batch material and mixed. Pressure is then applied to mixture such that the gas liquefies. The pressure is maintained during formation of a green body, maintaining the gas in a liquefied state. After formation of the green body, the pressure is removed whereby the gas returns to a gaseous state, creating pores in the green body. The green body may then be fired to produce a porous ceramic article.