Castor Oil Ethoxylate CO 36: A Versatile Powerhouse for Various Uses Imagine the transformation of castor oil, where its natural properties are enhanced through scientific advancements. This is precisely what Castor Oil Ethoxylate CO 36 offers â?? a remarkable combination of versatility and performance in the realm of surfactants. Unlike its original form, CO 36 possesses a unique structure, with 36 ethylene oxide units attached to the castor oil molecule, unlocking a multitude of possibilities.