1748 — Jean-Antoine Nollet, a French scientist-cleric interested in electricity and other scientific principles of his day, discovers how osmosis works through a semipermeable membrane.
1949 — After a hiatus of 200 years, in which osmosis was a phenomenon to be observed only in laboratories, an interest in natural-resource utilitarianism grew in the wake of World War Two. The University of California in Los Angeles began to conduct experiments into desalinating seawater in order to harvest drinking water from the ocean.
Mid-1950s — Working in conjunction with the University of Florida, UCLA saw the first freshwater being produced from seawater. However, the rate of flow per part of the system surface was too low for the process to be commercially viable.
1959 — UCLA researcher Sidney Loeb and Srinivasa Sourirajan, of the National Research Council of Canada, Ottawa developed a working Reverse Osmosis membrane using cellulose acetate polymer, a synthetic material. This style of membrane acted as a filter when tests were conducted by forcing high-solute water through it; for the first time, an artificial membrane strained water molecules while it repelled salt. The invention was so effective that it let fresh water pass through at a good enough rate for reverse osmosis to be proven as a backable process for commercial use. The idea was to compose a new technique to make asymmetric membranes with a thin enough “skin” layer held above a very porous and far thicker substrate region. John Cadotte of Film Tec Corporation had discovered that the process could be developed by the interfacial polymerization of two chemicals. Not only did this new membrane allow a good flux, or flow rate, but the membrane was also strong and durable, and it could even strain water through under normal water pressure. The process was named “reverse osmosis” as it ran in the opposite way to osmosis.
1965 — Coalinga, California became the site of the first-ever RO plant. Built with the assistance and direction of Loeb and J.W. McCutchan, the project attracted world attention as engineers from around the world descended. The ideal was to work seawater back into drinkable water affordably and on a large scale. Other pilot programs took off in La Jolla and Firebaugh, both in California, as different types of seawater were tested. Heavy industry was to benefit from these advances and contributions as clean water could now be produced in great amounts.
1977 — Cape Coral, Florida became the first municipality to use Reverse Osmosis on a grand scale, starting by processing three million gallons of water a day.
1985 — Cape Coral’s expanding population saw the corresponding growth of its RO plant, now capable of the production of 15 million gallons a day, the largest in the world.
1990s-2000s — It wasn’t long before the first home RO systems came up for sale. Caldotte’s patent for treating m-phenylene diamine and trimesoyl chloride became the standard for virtually all commercial RO membranes. By then turn of the Millennium, around 15,000 desalination plants would be in operation or in the stages of planning worldwide. Large desalination plants are only part of the dream to keep the depletion of the world’s clean water reserves in check, while RO membranes serve a multitude of different applications across the globe. The industry would continue to grow on a sure footing. After all, clean, drinkable water may one day become a highly prized commodity, given that a) it’s a resource challenged by environmental change and human impact, and b) it’s essential for all living things.
2016 — While some cities and even small counties enjoy the privilege of RO-purified water, the advent of home water purification systems just before the turn of the century has ensured that individual homeowners can make that all-important decision. With the growing popularity of health-conscious diets and concerns about water quality, home users can select from a wide array of home reverse osmosis systems. It may not occur to a buyer as he or she chooses between company names such as Apec or iSpring, but the truth is undeniable. RO technology may be one of the most important technologies humanity has accessed. This top scientific advancement has plenty of leverage for the near and far future.