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4. Moresi M., Sebastiani I. (2008) Pectin recovery from model solutions using a laboratory-scaleceramic tubular UF membrane module. J Membr Sci 322: 349–359.In this work the feasibility of the recovery of a commercial sample of citrus pectin from model solutions using atemperature- and pressure-controlled bench-top ultrafiltration (UF) plant equipped with a ceramic tubular, 20 kDanominal molecular weight cut-off (NMWCO), UF membrane module, was assessed. Several total recycle tests allowedthe assessment of the effects of transmembrane pressure difference (∆P), feed superficial velocity solute(v S ) and concentration (c BR ) in 26 the ranges of 0.4-4.2 bar, 4-6 m s -1 , and 2.2-30.4 kg m -3 , respectively, on thepermeation flux under a constant process temperature of 50°C. As c BR increased from about 2.2 to 10 kg m-3 thelimiting permeation flux (J P∞ ) almost linearly decreased from 125-195 to about 25-40 dm 3 m -2 h -1 , these values dependingon v S . For c BR rising from ~10 to 31 kg m -3 , J P∞ was almost constant or slightly tended to decline. Thechange in slope of the plot J P∞ -vs.-log(c BR ) was attributed to the transition from turbulent to laminar regime. Twodimensionless empirical regressions among the modified Sherwood, Reynolds and Schmidt numbers, valid in thelaminar or turbulent flow regime, enabled the estimation not only of the J P∞ values detected here in the total recyclemode, but also of the permeation fluxes observed by Pritchard et al. (1995) using a polyethersulphone, 37 65-kDa NMWCO, tubular module operating at 45°C, ∆P=2.5 bar and different feed superficial velocities (1.3-2.7 ms -1 ) with about 21% deviation. Moreover, such relationships yielded satisfactory simulation of two other independentvalidation tests performed in the batch mode with an average percentage error between the theoretical andexperimental fluxes of 15%.5. Moresi M., Sebastiani I., Wiley D. E. (2009) Experimental Strategy to Assess the MainEngineering Parameters Characterizing Sodium Alginate Recovery from Model Solutions byCeramic Tubular Ultrafiltration Membrane Modules. J Membr Sci 326: 441-452In this work an experimental procedure was established to assess the main engineering parameters characterisingthe ultrafiltration (UF) recovery of a commercial sample of sodium alginate from model solutions, using both alaboratory-scale and a pilot-scale plant equipped with ceramic tubular UF membrane modules.Several total recycle tests were performed in the laboratory-scale plant so as to assess the effects of transmembranepressure difference (∆P), feed superficial velocity (v S ) and solute concentration (c BR ) in the ranges of 0.5-4.5 bar, 4-10 m/s, and 3-22 kg m -3 , respectively, on the permeation flux under a constant process temperature of50°C. As c BR increased from approximately 3 to 7 kg m -3 , the limiting permeation flux (J P∞ ) decreased almostlinearly from 140-320 dm 3 m -2 h -1 (depending on v S ) to about 40 dm 3 m -2 h -1 , the latter value being independent ofv S . The change in slope of the plot J P∞ -vs.-log(c BR ) was shown to be due to the transition from turbulent to laminarflow.Two empirical dimensionless correlations relating the modified Sherwood, Reynolds and Schmidt numbers, validin the laminar or turbulent flow regime, enabled prediction of the permeation flux of two independent batch modevalidation tests at high and low initial feed solute concentrations to within