Separation of n-hexane - ethyl acetate mixture by azeotropic batch distillation with heterogeneous entrainers

In this article, a systematic study of the separation of the n-hexane - ethyl acetate mixture with an entrainer by heterogeneous azeotropic batch distillation is performed. Based upon the thermodynamic behaviour of the ternary mixtures, potential entrainers partially miscible with one or two original azeotropic components are chosen. In all cases, the entrainer adds a heterogeneous binary or ternary azeotrope that is the lowest boiling point in the ternary diagram. Therefore, it leaves the column by the overhead stream which is subcooled to get two liquid phases in the decanter. The phase with the highest amount of the original component is removed as distillate product whereas the entrainer – rich phase is continuously refluxed to the column. Considering methanol, acetonitrile, water and nitromethane as heterogeneous entrainers, screening was performed based on the composition of the unstable heteroazeotropic mixture, the ratio of both liquid phases in the condensed top vapour and the purity of the distillate product determined by the liquid – liquid envelope at the decanter temperature. The process feasibility analysis is validated by using rigorous simulation with the batch process simulator ProSimBatch. Simulation results are then corroborated in a bench experimental column for the selected entrainer, showing several advantages of heterogeneous batch distillation compared to homogeneous systems

Heterogeneous Extractive Batch Distillation of Chloroform - Methanol – Water : Feasibility and Experiments

A novel heterogeneous extractive distillation process is considered for separating the azeotropic mixture chloroform – methanol in a batch rectifying column, including for the first time an experimental validation of the process. Heterogeneous heavy entrainer water is selected inducing an unstable ternary heteroazeotrope and a saddle binary heteroazeotrope with chloroform (ternary diagram class 2.1-2b). Unlike to well-known heterogeneous azeotropic distillation process and thanks to continuous water feeding at the column top, the saddle binary heteroazeotrope chloroform – water is obtained at the column top, condensed and further split into the liquid – liquid decanter where the chloroform-rich phase is drawn as distillate. First, feasibility analysis is carried out by using a simplified differential model in the extractive section for determining the proper range of the entrainer flowrate and the reflux ratio. The operating conditions and reflux policy are validated by rigorous simulation with ProSim Batch Column® where technical features of a bench scale distillation column have been described. Six reproducible experiments are run in the bench scale column matching the simulated operating conditions with two sequentially increasing reflux ratio values. Simulation and experiments agree well. With an average molar purity higher than 99%, more than 85% of recovery yield was obtained for chloroform and methanol

Practical residue curve map analysis applied to solvent recovery in non-ideal binary mixtures by batch distillation processes

Batch distillation inherent advantages has initiated recent search for process feasibility rules enabling the separation of azeotropic or difficult zeotropic binary mixtures thanks to the addition of an entrainer. A systematic procedure enabling to find suitable process and eventually suitable entrainer for the separation of zeotropic or azeotropic binary mixture is described. It brings together into practical use batch distillation process feasibility rules, chemical affinity insight and thermodynamic data analysis available in the literature. The procedure has been implemented in a wizard computer tool and is illustrated on the separation of the water – acetonitrile binary homoazeotrope. Through this tool, all possible 224 feasibility rules and 326 batch distillation sequence processes are checked systematically for each entrainer

REGSOLexpert: Entrainer Selection Tool for waste solvent recovery by batch distillation processes

A general procedure to systematize the search of several alternatives enabling the separation of non-ideal binary mixtures such as pressure-swing distillation, azeotropic and extractive distillation is presented. The use of heterogeneous entrainers is specially highlighted

PLASMD BEARING A CDNA COPY OF THE GENOME OF BOVINE VIRAL DIARRHEA VIRUS, CHIMERIC DERIVATIVES THEREOF, AND METHOD OF PRODUCING AN INFECTIOUS BOVINE WRAL DARRHEAVIRUS USING SAD PLASMID

A plasmid bearing a cDNA copy of the genome of bovine viral diarrhea virus (BVDV), chimeric derivatives of the plasmid and a method of producing an infectious bovine viral diarrhea virus using the plasmid are disclosed. The invention relates to a plasmid DNA molecule that replicates easily in E. coli and contains a sufficient portion of the genome of BVDV, cloned as cDNA, to be a suitable template to produce RNA in vitro which, upon transfection into bovine cells, gives rise to infectious BVDV. The BVDV created by the process of the invention can be engineered for use as a vector in many advantageous applications

Heterogeneous batch distillation processes for waste solvent recovery in pharmaceutical industry

A summary about our experiences in the introduction of heterogeneous entrainers in azeotropic and extractive batch distillation is presented in this work. Essential advantages of the application of heterogeneous entrainers are showed by rigorous simulation and experimental verification in a bench batch distillation column for separating several azeotropic mixtures such as acetonitrile – water, n hexane – ethyl acetate and chloroform – methanol, commonly found in pharmaceutical industry

Simulation of an interacting system using a cellular automaton

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1987.Includes bibliographical references.by Peter Andrew Donis.B.S

Asistencias ventriculares de corta duración. Revisión bibliográfica y cuidados de enfermería

Los dispositivos de asistencia ventricular (DAV) son sistemas de bombeo que proporcionan apoyo mecánico y aportan soporte hemodinámico a un corazón de un paciente en estado crítico, incapaz de bombear de forma adecuada la sangre y mantener correctamente la circulación sanguínea 1, 2. Dentro de esta modalidad de soporte mecánico se encuentran las asistencias ventriculares de corta duración, cuyo plazo de mantenimiento varía en función de la fuente bibliográfica consultada, siendo los más habituales Impella ®, oxigenador de membrana extracorpórea (ECMO) y Levitronix Centrimag ®. Mención aparte se realiza al balón de contrapulsación intra- aórtico (BCIA), considerado un ejemplo de soporte mecánico circulatorio pero no un DAV propiamente dicho2, 3, 4. El papel de la enfermería en este aspecto es vital para ayudar a paliar la incertidumbre del paciente y la familia ante esta nueva modalidad terapéutica en el tratamiento del shock cardiogénico refractario, partiendo de un programa de cuidados generalizado para pacientes portadores de DAV y adaptándolo a la situación y características de cada uno de ellos de forma individualizada 5, 6, 7.Grado en Enfermerí

Determinación de anticuerpos de influenza aviar y newcastle en aves de traspatio de las comunidades circundantes a las granjas avícolas de reproductoras del municipio de San José Pinula, del departamento de Guatemala.

El presente estudio se realizó en aves de traspatio de 6 comunidades circundantes a las granjas avícolas de reproductoras del municipio de San José Pinula del departamento de Guatemala, con el objetivo de determinar la presencia de anticuerpos de las enfermedades de Influenza Aviar de baja patogenicidad y Newcastle. Para determinar la presencia de anticuerpos se utilizaron dos pruebas de laboratorio; la prueba de Inhibición de la Hemoaglutinación (HI) se utilizó para detectar la presencia de anticuerpos contra la enfermedad de Newcastle y la prueba de Inmunodifusión en Agar Gel (ID) para detectar presencia de anticuerpos contrala enfermedad de Influenza Aviar. El rol que las aves de traspatio representan como portadores y reservorios de enfermedades aviares de importancia económica y sanitaria para las granjas avícolas, se considera de mucha importancia en los estudios epidemiológicos. En esta investigación se generó información sobre el papel importante de la población de aves de traspatio en la epizootiología de las enfermedades de Newcastle (ENC; Paramixoviridae), y de Influenza Aviar (IA ; Orthomyxoviridae), determinando la presencia de anticuerpos en las aves de traspatio de las comunidades circundantes a granjas avícolas de reproductoras del Municipio de San José Pinula