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Fundamental Stage Design of Countercurrent Contact System: Solute Transfers between two Immiscible Solvents

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The Kremser’s equations have been serving successfully for many years as limiting design and analytical criterion for idealized countercurrent absorption, desorption and extraction systems that contains immiscible solvents. The performance equations developed by the Kremser subsequently revisited by Mott Sounders and George Granger Brown, and elaborated the same, which is popularly known as Kremser - Sounders- Brown equations. Much later G. E. Goring critically analyzed the Kremser - Sounders- Brown equations gave better insight. All these equations relate absorption factor or stripping factor or extraction factor, inlet and outlet mole fraction of the streams to the number of stages. This work, we have presented the derivation for the Kremser - Sounders- Brown equation in more simplified way in terms of mole ratio co-ordinates for the case of absorption and desorption. Further, the physical meanings underlying these performance equations were presented explicitly.

Keywords:Absorption, Countercurrent stage Operation, Desorption, Immiscible solvents, Kremser-Sounder-Brown equation, Mole ratio co-ordinates.


  1. A. Kremser, theoretical analysis of adsorption process, Natl. Petroleum News, 22(21), 1932, 42-48.
  2. M. Souders, and G. G. Brown, Fundamental design of absorbing and stripping columns for complex vapours,Ind.Eng.Chem.,24(5), 1932,519-522.
  3. G. E. Goring, A modified Kremser equation for stagewise countercurrent processes, Separation Science, 5(2), 1970, 113-120.
  4. Chandrasekhar Garlapati."A Derivation to Overall Murphree Efficiency from Individual Efficiencies for a Special Case in Staged Operations"Journal of Applied Science and Engineering Methodologies 3 (1), 2017, 435-439.
  5. R.E.Treybal, Mass Transfer Operations (New York: McGraw-Hill, 1982).
  6. G.S.Laddha and T. E. Degaleesan, Transport Phenomena in Liquid Extraction (New Delhi: Tata Mcgraw-Hill, 1976).