Until now, many scientific reports have been devoted to the effec

Until now, many scientific reports have been devoted to the effective treatment of surfactants employing advanced oxidation processes, but there is no available experimental study dealing with the optimization and statistical design of surfactant oxidation with the well-established H2O2/UV-C process.

RESULTS: Considering the major factors influencing H2O2/UV-C performance as well as their interactions, the reaction conditions required for the complete oxidation of a commercial non-ionic textile surfactant, an alkyl ethoxylate, were modeled and optimized using HDAC inhibitor central composite design-response surface methodology (CCD-RSM). Experimental results revealed

that for an aqueous non-ionic surfactant solution at an initial chemical oxygen demand (COD) of 450 mg L-1, the most appropriate H2O2/UV-C treatment conditions to achieve full mineralization at an initial pH of 10.5 were 47 mmol L-1 H2O2 and a reaction time of 86 min (corresponding to a UV dose of 30 kWh m(-3)).

CONCLUSION: CCD allowed the development of empirical polynomial equations (quadratic models)

that successfully predicted COD and TOC removal efficiencies under all experimental conditions employed in the present work. The process variable treatment time, followed by the initial COD content of the aqueous Elafibranor surfactant solution were found to be the main parameters affecting treatment performance, whereas PFTα cell line the initial H2O2 concentration had the least influence on advanced oxidation efficiencies. The H2O2 concentration and surfactant COD were found to be more important for TOC abatement compared with COD abatement. (C) 2009 Society of Chemical Industry”
“BACKGROUND: The energy demand of distillation-based systems

for ethanol recovery and dehydration can be significant, particularly for dilute solutions. An alternative separation process integrating vapor stripping with a vapor compression step and a vapor permeation membrane separation step, termed membrane assisted vapor stripping (MAVS), has been proposed. The hydrophilic membrane separates the ethanol-water vapor into water-rich permeate and ethanol-enriched retentate vapor streams from which latent and sensible heat can be recovered. The objective of this work was to demonstrate experimentally the performance of a MAVS system and to compare the observed performance with chemical process simulation results using a 5 wt% ethanol aqueous feed stream as the benchmark.

RESULTS: Performance of the steam stripping column alone was consistent with chemical process simulations of a stripping tower with six stages of vapor liquid equilibria (VLE). The overhead vapor from the stripper contained about 40 wt% ethanol and required 6.0 MJ of fuel-equivalent energy per kg of ethanol recovered in the concentrate.

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