Impact of Fluid Flow on Free Radical Polymerization in a Batch Reactor

In this work, the mixing process on a batch reactor is analyzed for the thermal synthesis of poly(acrylamide-co-sodium 2-acrylamide-2-methylpropane sulfonate) initiated by ammonium persulfate. The analysis is achieved by using tracer technology and computational fluid dynamics (CFD). ANSYS Fluent® software is used for numerical simulations. By studying the mixing time in the reactor, the injection point and the stirring speed are determined so that the kinetics of copolymerization is improved

Diseño de escenarios interactivos para el aprendizaje autogestivo de la Ingeniería Ambiental

El Escenario Interactivo de Aprendizaje (EIA) es una herramienta que facilita las relaciones multidireccionales entre los actores del proceso de enseñanza y aprendizaje, favoreciendo así un ambiente de compatibilidad con los objetivos pedagógicos que persiga el docente y con las necesidades que requiere cada alumno. Se tiene como objetivo el diseño de una interfaz gráfica (EIA) como un recurso didáctico para el aprendizaje autogestivo de los temas ambientales, combinando una variedad de herramientas virtuales para dar soporte a profesores y estudiantes y optimizar el proceso de enseñanza y aprendizaje. En cuanto a la plataforma seleccionada para ejecutar el EIA, en esta iteración, el rendimiento gráfico demostró operar correctamente en los equipos en que fue probado; por lo que mientras el modelado de nuevos objetos en iteraciones posteriores se mantenga dentro de los parámetros, la herramienta podrá ser aprovechada por la mayoría de los estudiantes.The Interactive Learning Scenario (EIA) is a tool that facilitates multidirectional relationships between the actors of the teaching and learning process, thus favouring an environment of compatibility with the pedagogical objectives pursued by the teacher and also with the needs that each student requires. This work aims to design a graphical interface EIA as a didactic resource for self-managed learning of environmental issues, combining a variety of virtual tools to support teachers and students, as well as optimize the teaching and learning process. Regarding the platform selected to execute the EIA, in this iteration the graphic performance demonstrated to operate correctly in the equipment in which it was tested; so as longas the modeling of new objects in subsequent iterations remains within the parameters, the tool can be used by most of the target students

An Early Study on the Synthesis of Lignin-Graft-(Net-Poly(acrylamide-co-N,N′methylenebisacrylamide)), Characterization of the Produced Copolymer, and Evaluation of Its Performance as Adsorbent for Lead Removal from Wastewater Purposes

A lignin-graft-(net-poly(acrylamide-co-N,N′methylenebisacrylamide)) copolymer was synthesized by conventional free-radical crosslinking copolymerization using conventional and microwave heating. Grafting of the polymer network onto lignin was confirmed by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), scanning electron microscopy (SEM)/energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), and elemental analysis. The performance of the modified materials for the removal of lead from water was evaluated. The materials obtained by the two types of heating showed excellent removal efficiencies: sample HLigAM4h, 96%; and sample HLigAMMW5, 86%. The maximum adsorption capacity of HLigAM4h was 209.82 mg g−1. The obtained copolymer (sample HLigAM4h) was characterized by X-ray photoelectron spectroscopy (XPS) and SEM/EDS after its evaluation as an adsorbent, which confirm the adsorption of Pb2+. This is the first of a series of studies on the topic, of a preliminary nature, with several other ones coming up in due time

Development of Enhanced Nanocomposite Preformed Particle Gels for Conformance Control in High-Temperature and High-Salinity Oil Reservoirs

In this paper, we describe the synthesis, characterization and evaluation of nanocomposite preformed particle gels (PPGs) for use as conformance control agents in high-temperature and high-salinity oil reservoirs. The chemical stability of conventional acrylamide (AM)-homopolymer-based PPGs was improved by incorporating an optimized ratio of new functional groups into their structure to withstand harsh reservoir conditions. The modified PPGs were synthesized via free radical crosslinking polymerization at room temperature using AM, vinylpyrrolidone (VP) and 2-acrylamido-2-methylpropane sulfonic sodium salt (AMPSNa) monomers and an N,N-methylenebis (acrylamide) (MBA) crosslinker. The mechanical properties of the PPGs were enhanced by adding a dispersion of modified bentonite (MB) to the formulation. The chemical and mechanical stabilities of the synthesized PPGs were evaluated at a high temperature (130 °C) and under high-salinity conditions using production water (with a TDS of 83 942.63 p.p.m.) and connate water (with a TDS of 254 873.09 p.p.m.), both of which were collected from an oil reservoir. The experimental results showed that PPGs prepared with 30 wt.% of a 1:1:1 molar mass ratio of AM, VP and AMPS monomers with 0.5 wt.% MBA and 2 wt.% MB exhibited the highest stability of the investigated PPGs under oil reservoir conditions