Removal of some pollutants (Basra, Azeri, and Rebco crude oils, diesel, gasoline, and 1/1 (w/w) diesel-gasoline mixture) from water by sorption using Romanian Merino wool as a natural sorbent was studied in this paper. Batch experiments were conducted at different levels of initial sorbent mass (1 and 3 g), oily water pH (5 and 10), and operating temperature (30 and 45 �C). The effects of these factors on wool sorption capacity were evaluated. The sorption capacity of more viscous fuels (crude oils), i.e., 4.13-21.87 g/g, increased with an increase in oily water pH and a decrease in initial sorbent mass and temperature. For less viscous pollutants (diesel, gasoline, and their mixture), the sorption capacity (3.32-9.19 g/g) increased with a decrease in sorbent mass, the effects of pH and temperature being negligible. Experimental results were processed according to a 2 3 factorial plan and regression equations between the process factors and sorption capacity were obtained. SEM analysis revealed that the removal process was governed by both adsorption and absorption mechanisms.

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Bioethanol is the most important biofuel produced by fermentation of sugars from various biomass types. The main disadvantages associated to this process consist in the negative effect of high ethanol concentration on the cell growth and in the separation cost of ethanol-water system resulted in the fermentation process. Sugar fermentation using Saccharomyces cerevisiae yeast coupled with bioethanol recovery by pervaporation has been modeled and simulated in this paper. In order to avoid the clogging of pervaporation membrane, the yeast cells were previously retained into an ultrafiltration unit. Three operating modes were analyzed and compared, i.e., classical batch fermentation (BF), batch fermentation coupled with external ultrafiltration and pervaporation (BFPV), and fed batch fermentation coupled with external ultrafiltration and pervaporation (FBFPV). Surface areas of ultrafiltration and pervaporation units were selected as process control variables.

The paper aimed at studying the performances of pervaporation separation of isopropanol-water system using a Pervatech ceramic membrane at various values of feed mixture flow rate (F=1000 kg/hr), feed water mass fraction (xF=0.1-0.2), operation temperature (t=60-90 �C), permeate pressure (pP=1000-9000 Pa) and water separation degree (sW=0.9, 0.95). Membrane total flux and separation factor were predicted applying a second order response surface model with 3 factors, i.e., xF, t and pP. An algorithm for estimating the membrane surface area was presented. Membrane area increased with sW and xF and its lowest values (A=13 m2 for xF=0.1 and A=24 m2 for xF=0.2) were attained for t=60 �C and pP=9000 Pa. These findings could be applied for optimizing the process of isopropanol dehydration by pervaporation.