Thermodynamic and Kinetic Aspects of Mercury Sorption on Activated Carbon in the Process of Mercury Bioreduction

A unique biotechnological method for remediation of industrial wastewater contaminated by toxic mercury,based on the enzymatic reduction of ionic mercury by live bacteria,has been developed by prof.Deckwer and co-workers at GBF (at present HZI), Germany,and implemented in a pilot-plant scale.The experience gained during operation of this installation led to the idea,that the process of bioremediation may be integrated in one bioreactor with the adsorption of mercury by immobilization of the bacteria onto the activated carbon.For this it was necessary to define several significant parameters of the activated carbon selected for the process and the adsorption process itself. The paper presents results of the equilibrium and kinetics investigations of the process of ionic mercury sorption from aqueous solutions onto 8 different types of activated carbon.The effective diffusion coefficients in the carbon particles were obtained from the transient-state experiments using a mathematical model of the process and the sorption isotherms as well as the saturation capacity of the sorbents in relation to ionic and metallic mercury were identified.From the temperature dependence of adsorption con- stants the values of adsorption enthalpy for both metallic and ionic mercury on activated carbon impregnated with sulfur were estimated.The obtained results enabled selection of the optimal sorbent for the fixed-bed activated-carbon bioreactor which will be applied for the modified,integrated process of biological detoxification of mercury in industrial wastewaters

Dynamic optimization of a gas-liquid reactor

The final publication is available at Springer via http://dx.doi.org/10.1007/s10910-011-9941-1A dynamic gas-liquid transfer model without chemical reaction based on unsteady film theory is considered. In this case, the mathematical model presented for gas-liquid mass-transfer processes is based on mass balances of the transferred substance in both phases. The identificability property of this model is studied in order to confirm the possible identifiable parameters of the model from a given set of experimental data. For that, a different modeled of the system is given. A procedure for the identification is proposed. On the other hand, the aim of this work is to solve the quadratic optimal control problem, using an explicit representation of the model. The problem includes some results on controllability, observability and stability criteria and the relation between these properties and the parameters of the model. Using the optimal control problem we study the stability of the system and show how the choice of the weighting matrices can improve the behavior of the system but with an increase of the energy control cost. © 2011 Springer Science+Business Media, LLC.This work has been partially supported by PAID-05-10-003-295 and by MTM2010-18228.Cantó Colomina, B.; Cardona Navarrete, SC.; Coll, C.; Navarro-Laboulais, J.; Sánchez, E. (2012). Dynamic optimization of a gas-liquid reactor. Journal of Mathematical Chemistry. 50(2):381-393. https://doi.org/10.1007/s10910-011-9941-1S381393502Bayón L., Grau J.M., Ruiz M.M., Suárez P.M.: Initial guess of the solution of dynamic optimization of chemical processes. J. Math. Chem. Model. 48, 28–37 (2010)Ben-Zvi A., McLellan P.J., McAuley K.B.: Ind. Eng. Chem. Res. 42, 6607–6618 (2003)Cantó B., Coll C., Sánchez E.: Structural identifiability of a model of dialysis. Math. Comp. Model. 50, 733–737 (2009)Cantó B., Coll C., Sánchez E.: Identifiability of a class of discretized linear partial differential algebraic equations. Math. Probl. Eng. 2011, 1–12 (2011)Craciun G., Pantea C.: Identifiability of chemical reaction networks. J. Math. Chem. 44, 244–259 (2008)Dai L.: Descriptor Control Systems. Springer, New York (1989)Deckwer W.D.: Bubble Column Reactors. Wiley, Chichester (1992)Kantarci N., Borak F., Ulgen K.O.: Bubble column reactors. Proc. Biochem. 40(7), 2263–2283 (2005)Kawakernaak H., Sivan R.: Linear Optimal Control Systems. Wiley-Interscience, New York (1972)Kuo B.C.: Automatic Control Systems, 6th edn. Prentice-Hall, Englewood Cliffs (1991)Navarro-Laboulais J., Cardona S.C., Torregrosa J.I., Abad A., López F.: Practical identifiability analysis in dynamic gas-liquid reactors. Optimal experimental design for mass-transfer parameters determination. Comp. Chem. Eng. 32, 2382–2394 (2008)Navarro-Laboulais J., López F., Torregrosa J.I., Cardona S.C., Abad A.: Transient response, model structure and systematic errors in hybrid respirometers: structural identifiabilit analysis based on OUR and DO measurements. J. Math. Chem. 44(4), 969–990 (2007)Patel R., Munro N.: Multivariable Systen. Theory and Design. Pergamon Press, New York (1982)Sondergeld K.: A generalization of the Routh–Hurwitz stability criteria and a application to a problem in robust controller design. IEEE Trans. Automat. Contr. AC-28(10), 965–970 (1983

Marktdaten zur Biotechnologie: Produkte und Reaktoren

Copy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Inaktivierung von rDNA in Abwaessern und Ueberstaenden aus biotechnologischen Prozessen Abschlussbericht

Kinetic data for the modelling of thermal rDNA inactivation have been compiled, and from these data a mathematical model has been derived. Based on a first order reaction rate law, the influence of temperature (100-140 C), pH and salt concentration is described by six parameters. As model systems the plasmid pBR322 as well as plasmid-containing cells (Escherichia coli 5K:pBR322, TG1:pPlac8) have been studied. At 134 C a reduction of rDNA concentration to < 1 ppm is achieved. On this basis the prototype of an inactivation plant has been constructed and tested. (WEN)Available from TIB Hannover: F95B1060+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Bioreaktoren: Ein Leitfaden fuer Anwender

SIGLEAvailable from Gesellschaft fuer Biotechnologische Forschung m.b.H., Braunschweig (DE) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Bestimmung der Feinstruktur der Phasenverteilung und der fluiddynamischen Grenzbedingungen des effektiven Einsatzes von Gas-Fluessig-Reaktoren (Blasensaeulen) unter Reaktionsbedingungen Abschlussbericht

SIGLETIB Hannover: D.Dt.F./AC 1000 (14,46) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman