Cadotte, John

Cadotte, John, R.S. King, R.J. Majerle, and R.J. Peterson, "Interfacial Synthesis in the Preparation of Reverse Osmosis Membranes," Journal of Macromolecular Science and Chemistry, A15,1981. 

The production by Loeb and Sourirajan of the first successful anisotropic membranes spawned numerous other techniques in which a microporous membrane is used as a support for a thin, dense separating layer. One of the most important of these was interfacial polymerization, an entirely new method of making anisotropic membranes developed by John Cadotte, then at North Star Research. Reverse osmosis membranes produced by this technique had dramatically improved salt rejections and water fluxes compared to those prepared by the Loeb-Souri-rajan process. Almost all reverse osmosis membranes are now made by the interfacial polymerization process, illustrated in Figure 3.20. In this method, an aqueous solution of a reactive prepolymer, such as a polyamine, is first deposited in the pores of a microporous support membrane, typically a polysul-fone ultrafiltration membrane. The amine-loaded support is then immersed in a water-immiscible solvent solution containing a reactant, such as a diacid chloride in hexane. The amine and acid chloride react at the interface of the two immiscible... 

Cellulose acetate and linear aromatic polyamide membranes were the industry standard until 1972, when John Cadotte, then at North Star Research, prepared the first interfacial composite polyamide membrane.8 This new membrane exhibited both higher throughput and rejection of solutes at lower operating pressure than the here-to-date cellulose acetate and linear aromatic polyamide membranes. Later, Cadotte developed a fully aromatic interfacial composite membrane based on the reaction of phenylene diamine and trimesoyl chloride. This membrane became the new industry standard and is known today as FT30, and it is the basis for the majority... 

To summarise, the development and remarkable success of commercial membrane processes for Uquid separations — RO, nanofiltration (NF), UF, and MF — would not have been possible without the discovery and subsequent development of high-flux, extremely thin (skinned) CA membranes by Srinivas Sourirajan and Sidney Loeb at UCLA, culminating in the development of TFC PA membranes by John Cadotte. Membrane technologies such as NF, PV and GS got the impetus from the work on RO in the 1950s and 1960s. These successes have led to the development of newer membrane processes such as membrane distillation (MD) and forward osmosis (FO). 

Cellulose acetate and linear aromatic polyamide membranes were the industry standard until 1972, when John Cadotte, then at North Star... 

In the 1970s researchers such as Robert Riley at Fluid Systems Division of UOP Inc. and John Cadotte at Midwest Research Institute developed thin-film composite membranes using polymeric materials such as polyetherurea and polyamide. These thin films offered reduced resistance to the flow of water across the membrane layer and allowed production of drinking-quality permeate at a pressure of less than 70 bars and 35% recovery. At these operating parameters the energy requirement was lowered to approximately 6.6 kWh/m. ... 

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