Lines of Research
1. Waste recovery
New alternatives for the reutilization of different types of wastes, such as rejections of sorting plants, end-of-life vehicles (ELV) and construction and demolition wastes (C&IW) are being explored in association with COGERSA. As ways of use, we are researching its direct use as alternative fuel, focusing on cement kilns, and their use by chemical and biological pathways.
2. Design, modelization and simulation of innovative chemical reactors
Our research group has a large experience in the rigorous simulation of chemical reactors (specially un-conventional ones) using advanced mathematical programs. The numerical resolution of the differential equations obtained in the mass, energy and momentum differential balances allows to obtain spatial and temporal profiles of the desired variable. For this purposes, different software packages are used (MATLAB, COMSOL). The first aim of this research is the development and optimization of catalytic reactors for the combustion of methane and volatile organic compounds organic (VOCs) in gas emissions, called reverse flow reactors. These devices allow recovering the heat produced in the reaction through periodic flow inversions. This idea has been extended later to the elimination of NOx. In this case, the periodic flow inversion allows the concentration of the reducing agent in the inside of the reactor, avoiding the emissions of this pollutant. Likewise, the group has also worked in the modelization of membrane reactors for the clean hydrogen production and the partial oxidation of hydrocarbons, collaboration carried out with Inasmet-Tecnalia, Instituto de Catálisis y Petroleoquímica and the Universidad Rey Juan Carlos. Additionally, the research group participates currently in a European Consortium (LOWCARB) supported by the Research Found for Carbon and Steal whose global aim is the minimization of the carbon trace of the mining activity in Europe. In this project, the group has worked on the design and simulation of both thermal and catalytic combustion reactors.
3. Development of catalysts for the catalytic oxidation of volatile organic compounds
The research group has worked in the development of catalysts for the catalytic combustion of several hydrocarbons and volatile organic compounds (paraffin, aromatic, chlorinated, oxygenated) coming from different industrial emissions. In this way, it has been developed catalysts resistant to the catalytic poisoning produced by sulfur compounds, selective catalysts for the chlorinated compounds combustion, etc. Also, kinetic studies of the combustion reactions with an inhibit effect and catalytic deactivation performance were evaluated.
4. Catalytic processes for the removal of organochlorinated compounds
The organochlorinated compounds constitute a major problem, because of their high toxicity and persistence in the environment. Besides, the methods based on the oxidation of these compounds, thermal or catalytic, gives rise to the formation of by-products even more toxic, such as the dioxins or the phosgene. The catalytic hydrodechlorination (reaction of the chlorinated compound with hydrogen in presence of a catalyst) was proposed as an economic alternative, clean and efficient for the treatment of these effluents. When the hydrodechlorination is complete, the reaction products are hydrocarbons and hydrogen chloride, both products easily recovered. It has been studied the application of this reaction to the removal of these compounds in organic phase (common in organic wastes), as well as in aqueous. The studies have included the development of catalysts in the study of kinetics and catalytic deactivation
5. Simulation and control of industrial processes (chemical reactors, crystallizers, distillations, etc.)
The research group has worked on different processes of simulation and control, some of them, in collaboration with the industrial sector (Bayer, DuPont, REPSOL, etc). Several examples are the design and simulation of extractive distillation units, design of control loops for precipitation and crystallization units (including programmed cooling procedures and detection of sewing point) in pharmaceutical industries, design of control loops for chemical reactors, optimization of leaching procedures for materials recovery from wastes and minerals, etc. Also the simulation and optimization of complete chemical processes using commercial simulation programs is also done in this research group.
6. Development of adsorbents and adsorption processes for environmental purposes such as elimination of VOCs, capture of CO2, removal of micropollutants in waters ...)
The CRC Group has worked extensively on the study of adsorption phenomena using the inverse gas chromatography technique. The main goal of these researches is the calculation of physic chemical properties which allow characterizing the interaction between the adsorbate and the adsorbents. In this way, systematic correlations between the adsorption strength and capacity, as well as chemical properties of the solid can be obtained. This technique has been applied to the characterization of commercial adsorbents (active carbon, alumina, zeolite), emerging materials (carbon nanotubes, carbon nanofibre, high surface area graphites or MOFs, etc.), and also to elucidate reaction networks. Additionally, in collaboration with IRC-CNRS, the research group has worked on the development of alkaline materials (desilicated zeolites, hydrotalcite derived materials, etc.) for the capture of CO2. From these researches it was obtained a low cost adsorbent based on magnesium oxide. In the field of aqueous phase adsorption, it is being studied the development of adsorption processes as a preconcentration technique of micropollutants in waters.
7. Catalytic Processes for biofuels production
The main scope of this research is the production of second generation biofuels from waste biomass, such as agroforestry wastes or cellulosic wastes. This transformation is based on catalytic processes: hydrolysis of the waste, reactions for increasing the length of the carbon chain (aldol condensation), and hydrogenation-deoxygenation reactions. Thus, a first step of hydrolytic hydrogenation for direct transformation of the cellulose and hemicellulose in polyols and aldehydes was studied. The next step was the aqueous-phase aldol condensation reaction, for transforming carbonyl compounds with five or six carbon atoms in compounds with larger carbon length. These compounds can become diesel fuels through complete hydrogenation processes, reaction also studied in our group. Another topic of this research line is the hydrotreatment of pyrolysis oils, rich in aromatic oxygenated compounds. In this way, processes for upgrading of products obtained from biomass such as bioethanol or acetone were studied. The purpose was to obtain chemical products with higher added value (Guebert alcohols, isophorones, etc).