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The assessment key factors of any bioprocess sustainability are mainly its interaction towards the environment and the capacity to control any generated pollution, beside its social and economical aspects. These factors have direct impact on the decision-making regarding the choice of the relevant technologies at the early stages of the bioprocess design. Therefore, in the present study we assessed the environmental impact of a chosen model process, namely for the production L-lysine by fermentation using Corynebacterium glutamicum and glucose as the bacteria and the substrate, respectively. We used the Super Pro Designer® version 9.0 software to compute mass balances of the entry and exit streams. The results, together with all relevant impact categories, which are classified according to calculated mass indices, were used for environmental assessment to deduce the set environmental parameters, as environmental factors and indices. In order to optimize the environmental performance of the bioprocess, other indices were also calculated. For instance, the results showed that Water was the most influential relevant component from mass point of view with 20.97 and 22.32 kg/kg P for input and output, respectively. Regarding the fact that Water is an exhaustible natural resource, it is necessary to anticipate its recycling. Therefore, as a second step a part of the water recovered during the purification of the main product was recycled along with L-Lysine wastes. This led to important mitigations of the environmental impacts of Water and L-Lysine as well to a production increase of the latter. [ABSTRACT FROM AUTHOR]

The research study below aims to characterize the hydrodynamics of a Moving Bed Biofilm Reactor filled with Kaldnes K1. Firstly, find the type of reactor (stirrer or piston) and finally set the operating conditions for carrying out the biological denitrification in an MBBR reactor. The hydrodynamics were determined by means of pulse tracer tests and by calculating distribution curves of the residence time at different stirring speeds (100 - 300 rpm), for different support infill (0 - 165.2 g) and at different influent feed rates (0.1 - 2 L.h-1). The moving bed biofilm reactor (MBBR) showed rector behavior, it is a perfectly stirred reactor, and the optimaloperating conditions are for stirring speeds of 100 rpm, quantities of support of 165.2 gand afeed rate 0.816 L h-1. [ABSTRACT FROM AUTHOR]

Abstract: Activated carbons were prepared by the pyrolysis of coffee grounds impregnated by phosphoric acid at 450°C for different impregnation ratios: 30, 60, 120 and 180wt.%. Materials were characterized for their surface chemistry by elemental analysis, “Boehm titrations”, point of zero charge measurements, Infrared spectroscopy, thermogravimetric analysis (TGA); as well as for their porous and morphological structure by Scanning Electron Microscopy (SEM) and nitrogen adsorption at 77K. The impregnation ratio was found to govern the porous structure of the prepared activated carbons. Low impregnation ratios (<120wt.%) led to essentially microporous and acidic activated carbons whereas high impregnation ratios (>120wt.%) yielded to essentially mesoporous carbons with specific surface areas as high as 925m2 g−1, pore volume as large as 0.7cm3 g−1, and neutral surface. The activated carbons prepared from coffee grounds were compared to a commercial activated carbon (S BET ∼1400m2 g−1) for their adsorption isotherms of methylene blue and “Nylosan Red N-2RBL”, a cationic and anionic (azo) dye respectively. The mesoporous structure of the material produced at 180wt.% H3PO4 ratio was found to be appropriate for an efficient sorption of the latter azo dye. [Copyright &y& Elsevier]

The preparation of new adsorbents based on the coating of a poly(4-vinylpyridine) (P4VP) polymer onto industrial bentonites was investigated. Two ways of synthesis were investigated, using dibromohexane (DBH) or its absence as a difunctional quaternizing agent in order to fasten the polymer by cross-linking. Several parameters (reagents ratio, type of bentonite, chemical stability in liquid media) were studied. Qualitative (IR and RMN spectroscopies) and quantitative (thermogravimetric) analyses of the samples were carried out. [Copyright &y& Elsevier]