The Essex County prosecutor's office says an arrest warrant has been issued for 47-year-old Byron Stokely, of Irvington.
Police say Stokely threw a pot of hot water and oil on his ex-wife while she slept on March 29.
The prosecutor's office says the woman was badly burned on her face and upper body and remains hospitalized.
Police say Stokely also stole the victim's house keys and vehicle, which he used to leave the scene.
The vehicle has since been recovered.
Anyone with information is asked to contact the Essex County prosecutor's office.