Evaluation of polymeric membranes performance in multicomponent conditions
Polymeric membranes are a sustainable alternative to traditional, energy-intensive separation methods in many applications such as gas separation and Carbon Capture. A precise evaluation of the membrane performance in realistic conditions and in the presence of impurities is required to cut the process costs and extend the membranes lifetime.
One of the main issues is associated, especially in the process of natural gas and biogas purification, to the presence of CO2, which promotes membrane softening and exhibits a non-ideal behavior engaging competition with the other gases. Such aspects require tailored and time consuming experiments.
In this activity, experimental data are collected with a sophisticated equipment which allows to monitor the behavior of binary and ternary mixtures in high performance membranes. The data are used to generate generalized relationships and provide validation to predictive thermodynamic and molecular models which can extend the experimental results in wide operative ranges and offer a fundamental insight of the process.
The results of such project will allow engineers to design and select more efficient membrane process conditions and materials, and expand the range of application of membrane technologies.
Related Papers:: 2021(3) 2021(2) 2021 2020 2019 2019 (Open Access) 2017 2014 2014
Biodegradable materials and green solvents for use in separation applications:
this is a new line of research in which entirely bio renewable and biodegradable polymers, fully dissolvable in seawater, are tested for the gas separation performances.
Membrane technology is a valid alternative to traditional gas separation processes and a promising solution for Carbon Capture. Even though membrane materials are usually polymer-based, end-of-life treatment planning seldom enters process design considerations.
Using degradable biopolymers could increase the sustainability of membrane technology, which is conquering market shares owing to its positive environmental impact.
The ultimate purpose of this project is to promote a circular economy mindset through the analysis of potential applicability of bio-based polymers in typical industrial applications.
Membranes are produced replacing traditional toxic solvents with greener ones, and the films obtained are tested for potential use in gas separation and CO2 capture applications. The activity developed covers: Optimization of the preparation protocol and solvent; measurement of gas solubility, permeability and selectivity of the membrane; molecular simulation of the polymeric materials and of the gas sorption and transport therein; evaluation of key structural parameters to improve separation performance.
Recent publications: New sustainable routes for gas separation membranes: The properties of poly(hydroxybutyrate-co-hydroxyvalerate) cast from green solvents, Open Access, 2022
Development and testing of innovative materials for membrane separations
New material concepts are studied to boost the transition to sustainable separation technologies.
In one study polymeric nanofibers chemically functionalized to have active CO2 capturing ability are synthesized and processed into a compact form.
Related Papers:Evaluation of electrospun nanofibrous mats as materials for CO2 capture: A feasibility study on functionalized poly(acrylonitrile) (PAN), 2018
Multiscale strategies for modeling separation materials
Sustainable separation processes involving solid selective materials, e.g. polymeric and nanostructured membranes, allow to consume less energy than solvent-based processes requiring thermal regeneration, or cryogenic ones.
The separation performance of separation materials can be evaluated with different simulation strategies, from the innovative macroscopic equations of state used for polymeric phases (e.g. SAFT and related ones) to atomistic methods (Molecular Dynamics and Montecarlo). Intermediate scale models are also available such as coarse grained and mesoscale techniques as well as computational fluid dynamics tools.
Multiple scale approaches can combine the computational efficiency of macroscopic methods with the accuracy and predictive power of atomistic ones, especially when complex materials such as those including crystalline structures and nanofillers with enhanced selective properties are concerned (e.g. graphene, MOFs etc.).
The separation of interest in this project is mainly CO2 capture and natural gas/biogas purification, but other processes such as water purification are not excluded a priori.
The modeling strategies developed within the project will be validated against experimental data.
Related Papers: A multiscale approach to predict the mixed gas separation performance of glassy polymeric membranes for CO2 capture: the case of CO2/CH4 mixture in Matrimid®, 2017
Development of multiscale models for materials for Hydrogen and Supercritical CO2 handling
This activity, in collaboration with the Dutch Polymer Institute and several companies, is devoted to developing hierarchical simulation strategies to predict the behavior of barrier materials in extreme conditions during H2 handling.
The project develops an integrated simulation chain for the sorption and transport properties of high performance, multiphase materials, such as semi crystalline polymers or nanocomposites for challenging industrial applications. A Molecular Dynamics (MD) simulation of the phases is bridged with macroscopic methods in a hierarchical approach adopting key material parameters and producing structure-property correlations useful to guide the design and the optimization of such materials, as well as to reduce the number of experimental tests required. A comprehensive, dedicated experimental campaign is designed and performed to validate and integrate the simulation approach.
A comprehensive theoretical framework for the sub and supercritical sorption and transport of CO2 in polymers, 2022
Modelling solubility in semi-crystalline polymers: a critical comparative review, 2022 Open Access
An equation of state (EoS) based model for the fluid solubility in semicrystalline polymers, 2014
Development of materials for sustainable hemodialysis processes:
Hemodialysis is a life-saving treatment which requires an exceptional amount of water. Ultrapure water is required to remove toxins from the blood of patients. The development of materials usable as membranes or adsorbent with purification ability for spent dialysate streams allows to reduce the amount of water required and to render the treatment available to more peopleand in remote places.
This project is carried out thanks to funds from the Royal Society of Edinburgh and Kidney Research UK
Related paper: Mixed Matrix Membranes Adsorbers (MMMAs) for the Removal of Uremic Toxins from Dialysate, 2022 Open Access
Development of mixed matrix membranes for membrane separations
In recent years a number of new materials has entered the picture into the membrane world: new high performance polymers, 2d nanomaterials like graphene, crystalline porous materials like Metal Organic Frameworks, etc. Due to polymer flexibility and processability, a feasible solution seems the one of incorporating variable percentages of such fillers in the polymer and produce thin films out of them.
The activity regards the addition of graphene and graphene oxide to polymers, as well as the addition of Zeolite and ZIF-8. The aim is to provide emerging separation processes, like CO2 capture, with improved materials and possibly provide also an explanation to the observed behavior with the use of models.
Related papers :
-An analysis of the effect of zif-8 addition on the separation properties of polysulfone at various temperatures, 2021, Open Access
-Mixed matrix membranes based on torlon® and ZIF-8 for high-temperature, size-selective gas separations, 2022, Open Access
-Enhancing the separation performance of glassy PPO with the addition of a molecular sieve (ZIF-8): Gas transport at various temperatures 2020 Open Access
-Reducing ageing of thin PTMSP films by incorporating graphene and graphene oxide: Effect of thickness, gas type and temperature 2018
-Permeability and selectivity of PPO/graphene composites as mixed matrix membranes for CO2 capture and gas separation 2018 Open Access
-Effect of relative humidity on the gas transport properties of zeolite A/PTMSP mixed matrix membranes 2015
-Effect of Graphene and Graphene Oxide Nanoplatelets on the Gas Permselectivity and Aging Behavior of Poly(trimethylsilyl propyne) (PTMSP) 2015