There is disclosed a process and device for Forward Osmosis (FO) Pressurized Device (FOPD) in general and one hydraulically coupled to a reverse osmosis (RO device for a FOPRO (Forward Osmosis Pressurized Reverse Osmosis). Specifically, there is disclosed a passive device (that is, not needed energy input) for using forward osmosis to generate significant hydraulic pressure that can be used to drive a reverse osmosis process, wherein the reverse osmosis process (not needed external energy to run pumps) can separate salt from salt water to generate potable water from water with high salt content (such as sea water, urine, sweat, brackish water and the like).