Chemical Process Engineering and Forest Products Research Centre

Computational, Statistics and Materials (CEM)

Research Scope:

The efforts of the CEM group are primarily directed to the study of new materials through a combination of theoretical and experimental approaches. The research activities span over different but somehow interconnected areas, including the production of environmental friendly fuels, development and preparation of (nano)materials, characterization techniques, and advanced modeling and simulation issues.

The group is currently searching for new synthetic routes to transform crude glycerol, a by-product of biodiesel production, in ethers derivatives of industrial value. Within the scope of nanotechnology, and taking advantage of the accumulated experience in the field of energetic materials, work is continuing in exploring new uses of sol-gel chemistry to synthesize nanomaterials for engineering applications, namely in aerospace, biomedical and environmental areas. The group also gathers many skills in the characterization of materials, with special emphasis in the thermal analysis of materials.

The modelling/simulation domain is covered by different broad categories. One lies in the field of advanced statistical, such as study of the performance of several robust estimators for nonlinear regression both in single and multiresponse models. Advanced numerical methods are being applied in the development of numerical software for steep front chemical engineering models, namely to test and validate adaptive mesh refinement strategies. Operating conditions optimization and modern control strategies constitute other areas of investigation within the group. A new goal being pursued is the study and practical use of the complexity approach, namely by using a cellular automaton as the framework for our computational implementation of the KCL-PAKKA model for the 3D structure of paper. Molecular modeling and simulation is another line of research that looks toward product engineering guided by a unified approach, which incorporates theory, molecular modeling/simulation, and experiment. High-performance computing is a crucial element in such approach, in which the major challenge is a multiscale modeling, starting from the subatomic level and expanding to manifold length and time scales.

Specific areas:

Nanomaterials – Sol-gel technology for the synthesis of different Si/metal oxides. Modeling and Simulation in Chemical Engineering and Paper Engineering.

Cellular Automata for modelling of paper and textile nanowebs. Adaptive grids for the solution of PDEs.

Energy – Biofuels – Production and characterization of second /third generation biofuels.

Combustion and Detonics – Formulations and equilibrium calculations of energetic materials. Synthesis of ceramics from energetic materials.

Thermal analysis of materials – Thermal characterization of materials. Thermophysical and thermochemical properties of materials.

Molecular modeling and simulation by high performance computing – Ab initio, DFT, and (classical and ab initio) molecular dynamics methods. Multiscale molecular modeling/simulation in product engineering.

(Recent) Research:

Durães, L., Ochoa, M., Rocha, N., Hernandez, J., Duarte, N., Redondo, V., Portugal, A., “Effect of the Drying Conditions on the Microstruture of Silica Based Xerogels/Aerogels”, Journal of Nanoscience and Nanotechnology, 2011. (Accepted.)

Durães, L., Oliveira, O., Benedini, L., Costa, B. F. O., Matos Beja, A., Portugal, A., “Sol-Gel Synthesis of Iron(III) Oxyhydroxide Nanostructured Monoliths Using Fe(NO3)3∙9H2O/CH3CH2OH/NH4OH Ternary System”, Journal of Physics and Chemistry of Solids, 2011. (Accepted.)

Curto, J.M.R., Conceiçao, E.L.T., Portugal, A.T.G., Simões, R.M.S., "Three dimensional modelling of fibrous materials and experimental validation", Material Science and Engineering, 2011. (Accepted).

Paulo Brito, António Portugal "Adaptive Collocation Methods for the Solution of Partial Differential Equations" in Innovations in Computing Sciences and Software Engineering, DOI 10.1007/978-90-481-9112-3_85, T. Sobh, K. Elleithy (eds.), Springer Science+Business Media B.V, 2010.

Conceição,E.L.T.,& Portugal, A.A.T.G. "Finite-sample comparison of robust estimators for non-linear regression using Monte Carlo simulation: Part I. Univariate response models ", Computers and Chemical Engineering , 2010. (in press)

A. C. Fonseca, S. Jarmelo, R. A. Carvalho, R. Fausto, M. H. Gil, P. N. Simões. "1H-NMR Spectroscopic and Quantum Chemical Studies on a Poly(Ester Amide) Model Compound: N_alpha-Benzoyl-L-Argininate Ethyl Ester Chloride. Structural Preferences for the Isolated Molecule and in Solution", J. Phys. Chem. B, 2010, 114: 6156-6164.

Durães L., Campos J., Portugal A.. “Thermite Reactions”, in High Temperature Processes in Chemical Engineering, Lakner M (Ed.), Verlag ProcessEng Engineering GmbH, 2010, 277-307. (ISBN: 978-3-902655-09-7)

Group members:

Ana Filipa Avelar Borba

António Alberto Torres Garcia Portugal (Coordinator)

António Guiomar

Hajar Maleki

Joana Maria Rodrigues Curto

Luísa Maria Rocha Durães

Maria Helena Mendes Gil

Maria José Moura

Maria Margarida Lopes Figueiredo

Natércia Cristina Pires Fernandes

Paulo Miguel Pereira de Brito

Pedro Nuno Neves Lopes Simões