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-The prediction of interfacial area in agitated dispersions is of considerable importance in heat and mass transfer operations and in certain heterogeneous reactions. Rietema (11) discusses control of reaction rate in a stirred-tank reactor through control of drop size and interfacial area. Interfacial area control also plays an important role in liquid-liquid extraction (15), dispersion polymerization (7, 8), and direct-contact heat transfer (18).When two immiscible liquids are agitated, a dispersion is formed in which continuous breakup and coalescence of drops occurs. After some time a dynamic equilibrium is established between breakup and coalescence and a spectrum of drop sizes results. The average drop size and the size distribution will depend upon conditions of agitation as well as hysical properties of the two liquids. Drops are believex (6) to be broken up by turbulent pressure fluctuations in the neighborhood of the drop surface. Coalescence may occur when drops collide. In a dilute dispersion coalescence will be minimal, and the e uilibrium ess alone.Despite the fact that the drop size distribution is a significant factor apart from its influence on the average particle size and the total interfacial area, no information exists from which one may predict the distribution function, and the manner in which it changes, with agitation parameters and physical properties of the immiscible phases. The goal of this work was to develop such information over a wide range of pertinent parameters and properties and to imbed these results within the framework of a rational theory.A fair1 extensive literature exists with regard to the average irop size obtained in dispersions. A critical discussion of this literature may be found in reference 2. Only the most pertinent references are reviewed here.

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University of Rochester, Rochester, N e w Y a r kAlthough Newtonian jet stability has been the object of numerous experimental and theoretical studies, the total problem of jet disintegration is by no means solved. Theories available in the literature are only applicable to low-speed laminar jets in stagnant air. In practice, the stability of a liquid jet may be influenced. by the ambient medium, turbulence in the nozzle, and the extent of development of the velocity profile. None of these factors has received adequate study. This work presents the beginning of a systematic evaluation of the role played by these factors in the destabilization of a liquid jet. Correlations are presented for predicting the stability of both turbulent and high-speed laminar jets in stagnant air.

aration was obtained using a membrane containing 20% sulfolane.The membrane behavior in the lower sulfolane concentration range probably results from a complicated SO2 solubility effect which changes with pressure and the amount of sulfolane in the membrane in a nonlinear manner. The decreased membrane selectivity and high flux at sulfolane compositions greater than 12.8% probably is due to over-plasticization which causes pin-hole leaks.An addition level of 8.2% sulfolane was chosen for further parameter studies.

Viscoelast ic J e t Stability This paper, one of a series (3, 4, 10) on the stability of liquid jets, is especially concerned with jets formed by extrusion of viscoelastic liquids from long capillaries into still air. An investigation of the role played by elasticity in altering the growth rate of infinitesimal disturbances has been conducted, and the experimental results can be rationalized through a simple viscoelastic stability analysis.The phenomenon studied is the breakup into droplets F. William Kroesser is at Tufts University, Medford, Massachusetts.

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