Ce travail porte sur la fabrication des structures photoniques (SPs) à base de polymères etleurs applications en optique non-linéaire. Dans la première partie, nous avons démontré lafabrication des SPs souhaitées par la méthode d’interférence. En particulier, l’interférencede deux faisceaux laser avec une exposition multiple est démontrée théoriquement etexpérimentalement comme un meilleur choix pour la fabrication des structures souhaitées,qui sont uniformes et de grande taille. Diverses structures à 1D, 2D, et 3D, périodiques etquasi-périodiques sont fabriquées avec succès dans la résine SU8. Nous avons égalementdémontré un moyen pour surmonter l’effet d’absorption de la photorésine, qui impose unelimitation de l’épaisseur des structures, en ajoutant un faisceau laser uniforme en sensopposé par rapport à deux faisceaux d’interférence. Les SPs fabriquées deviennent plusuniformes et leur épaisseur augmente jusqu’à 25 μm. Une autre approche utilisant laméthode d’absorption ultra-faible à un photon a également été mise en oevre montrant lapossibilité d’obtenir des SPs avec une épaisseur jusqu’à 600 μm. De plus, en utilisant latechnique d’interférence et l’effet de transport de masse, nous avons également démontré lafabrication des structures à relief de surface (SRG), avec une profondeur contrôlable, dansdes polymères passives (SU8) et des polymères actives (DR1/PMMA). Dans la deuxièmepartie, nous avons utilisé ces structures pour l’amélioration de la génération de secondeharmonique des matériaux polymères par deux manières différentes: quasi-accord de phase(QPM) et mode de résonance de guide d’onde (WRG). Les structures de QPM permet desurmonter le déphasage entre les ondes fondamentale et harmonique, et par conséquenceaugmente le rendement du taux de conversion. En outre, les structures de guide d’ondeavec une surface modulée (WRG) ont également été démontrées comme une excellenteméthode permettant d’amplifier le signal de SHG par un facteur de 25. / This dissertation deals with the fabrication of various polymer-based photonic structures(PSs) and their applications in nonlinear optics. In the first part, we have demonstratedthe fabrication of desired PSs by interference lithography technique. The two-beam interferencemethod is theoretically and experimentally demonstrated as a best choice forfabrication of all kinds of PSs with large and uniform area. Desired 1D, 2D, and 3D,periodic and quasi-periodic PSs are successfully fabricated on SU8 photoresist. We alsodemonstrated a way to overcome the material’s absorption effect, which imposes a limitationof PSs thickness. By adding one more exposure of a uniform laser beam in oppositedirection of two interfering beams, the fabricated PSs became more uniform and theirthickness increased to 25 μm. A tentative of using low one-photon absorption techniquewas also realized showing the possibility to obtain a PS with a thickness upto 600 μm.Furthermore, by using the interference technique combined with mass transport effect,we have demonstrated the fabrication of desired surface relief grating structures, with acontrollable depth, on passive polymer (SU8) and active polymer (DR1/PMMA). In thesecond part, we applied these fabricated structures for enhancement of nonlinearity ofpolymer materials by two different ways: quasi-phase-matching (QPM) and waveguideresonance grating (WRG). Both theoretical calculation and experimental realization ofthese techniques have been investigated. The QPM structures allowed to overcome thephase mismatch of fundamental and harmonic waves, thus increasing the conversion efficiency.The second-harmonic generation (SHG), one of the most important applicationsof frequency conversion, is significantly enhanced thanks to the QPM condition. Anothermethod basing on the WRG structures allowed to increase the intensity of fundamentalwave, thus enhancing the SHG signal by a factor of 25.

A novel active material for controllable, high work density applications was designed, fabricated, analyzed, and tested. This active material uses a lens-shaped element to implement simple shear motion with gas pressure actuation. The lens element is a bladder-filled Kevlar fabric embedded in a polyurethane matrix. The polyurethane’s hyperelastic material parameters were found by experiment and estimated by numerical analysis. The Ogden material constant set found shows good agreement within the shear actuator’s working range. A fabricated, single-element shear actuator reached 34.2% free shear strain when pressurized to 1.03 MPa. A unitary shear actuator was modeled as were single-acting and dual-acting shear actuator arrays so that solitary and multi-cell behaviors were estimated. Actuator work performance and power from nonlinear finite element analysis found conventional work density is 0.2289 MJ/m3 and 0.2482 MJ/m3, for the singleacting and double-acting shear actuator, respectively. Scientific work densities are 0.0758 MJ/m3 and 0.0375 MJ/m3, for single-acting and double-acting shear actuators, respectively. Calculation shows the volumetric power for a single-acting shear actuator is 0.4578 MW/m3 and 0.4964 MW/m3 for the double-acting shear actuator. Finally, a nastic actuator is applied to twist a generic structural beam. The nasticmaterial actuated structure has an advantage over conventional actuator systems. Work per unit volume for nastic materials is 2280~8471% higher than conventional, discrete actuators that use electric motors. When compared by work per unit mass, this nastic actuator is 2592~13900% better than conventional actuator because nastic actuator is made from lighter materials and it distributes the actuation throughout the structure, which eliminates connecting components. The nastic actuator’s volumetric power is 2217~8602% higher than conventional actuators. Finally, the nastic actuator is 2656~14269% higher than conventional actuators for power per unit mass.

Grain storage is an essential part of the food production chain. Therefore, pre- venting grain deterioration is a key issue in a grain storage system. There are several causes for spoilage, all resulting in grain quality and quantity loss. One approach to detect incipient spoilage is by detecting the produced volatiles. In the past, many sensors for detecting volatiles have been developed and are used in industry. However, most of the commercial gas sensors are bulky with high power consumption, mainly limited in range of operating temperature, or require a restricted control over temperature and humidity. This thesis describes the design, fabrication and evaluation of a gas sensor capable of detecting volatiles and considers the potential use of polymer- based sensors. Conductive polymer-based sensors have been reported sensitive to a wide range of volatiles but are commonly evaluated under a controlled environment. Conventional sensor reproducibility and repeatability are also a concern due to the difficulties associated with polymer composite film preparation. In addition, current studies have not fully explored sensor properties in response to humidity, a common factor in any environment, and a variable parameter in grain storage facilities. Moreover, these sensors suffer from ambient temperature dependency as they work based on partitioning mechanism. To enhance sensor performances and eliminate the temperature dependency, a new sensor structure is proposed. The new design uses standard lithography process to fabricate a thermally isolated cantilever containing interdigitated electrodes and a micro-heater to efficiently heat and maintain a constant temperature throughout the interdigitated electrodes. This structure eliminates sensor response drifts caused by ambient temperature variations. Capacitive measurements are performed as the means of volatile detection, which simplify the use of polymers due to the absence of conductive filler and the challenges associated with it. Frequency spectroscopy provides additional information regarding the presence of volatiles compared to conventional resistive sensors, since mechanisms other than swelling are involved. Moreover, frequency and temperature modulations can be employed to further enhance sensor performance, enabling the use of a reduced number of sensors in a sensor array.

Grain storage is an essential part of the food production chain. Therefore, pre- venting grain deterioration is a key issue in a grain storage system. There are several causes for spoilage, all resulting in grain quality and quantity loss. One approach to detect incipient spoilage is by detecting the produced volatiles. In the past, many sensors for detecting volatiles have been developed and are used in industry. However, most of the commercial gas sensors are bulky with high power consumption, mainly limited in range of operating temperature, or require a restricted control over temperature and humidity. This thesis describes the design, fabrication and evaluation of a gas sensor capable of detecting volatiles and considers the potential use of polymer- based sensors. Conductive polymer-based sensors have been reported sensitive to a wide range of volatiles but are commonly evaluated under a controlled environment. Conventional sensor reproducibility and repeatability are also a concern due to the difficulties associated with polymer composite film preparation. In addition, current studies have not fully explored sensor properties in response to humidity, a common factor in any environment, and a variable parameter in grain storage facilities. Moreover, these sensors suffer from ambient temperature dependency as they work based on partitioning mechanism. To enhance sensor performances and eliminate the temperature dependency, a new sensor structure is proposed. The new design uses standard lithography process to fabricate a thermally isolated cantilever containing interdigitated electrodes and a micro-heater to efficiently heat and maintain a constant temperature throughout the interdigitated electrodes. This structure eliminates sensor response drifts caused by ambient temperature variations. Capacitive measurements are performed as the means of volatile detection, which simplify the use of polymers due to the absence of conductive filler and the challenges associated with it. Frequency spectroscopy provides additional information regarding the presence of volatiles compared to conventional resistive sensors, since mechanisms other than swelling are involved. Moreover, frequency and temperature modulations can be employed to further enhance sensor performance, enabling the use of a reduced number of sensors in a sensor array.

The development of enzymatic biosensors and enzymatic biofuel cells (EBFCs) has been a significant area of research for decades. Enzymatic catalysis can provide for specific, reliable sensing of target analytes as well as the continuous generation of power from physiologically present fuels. However, the broad implementation of enzyme-based devices is still limited by low operational/storage stabilities and insufficient power densities. Approaches to improving upon these limitations have focused on the optimization of enzyme activity and electron transfer kinetics at enzyme-functionalized electrodes. Currently, such optimization can be performed through enzyme structural engineering, improvement of enzyme immobilization methodologies, and fabrication of advantageous electrode materials to enhance retained enzyme activity density at the electrode surface and electron transfer rates between enzymes and an electrode. In this work, varying electrode materials were studied to produce an increased understanding on the impacts of material properties on resulting biochemical, and electrochemical performances upon enzyme immobilization and an additional method of electroactive enzyme-based optimization was developed through the use of polymer-based protein engineering (PBPE). First, graphene/single-wall carbon nanotube cogels were studied as supports for membrane- and mediator-free EBFCs. The high available specific surface area and porosity of these materials allowed the rechargeable generation of a power density within one order of magnitude of the highest performing glucose-based EBFCs to date. Second, two additional carbon nanomaterial-based electrode materials were fabricated and examined as EBFC electrodes. Graphene-coated single-wall carbon nanotube gels and gold nanoparticle/multi-wall carbon nanotube-coated polyacrylonitrile fiber paddles were utilized as electroactive enzyme supports. The performance comparison of these three materials provided an increased understanding of the impact of material properties such as pore size, specific surface area and material surface curvature on enzyme biochemical and electrochemical characteristics upon immobilization. Third, PBPE techniques were applied to develop enzyme-redox polymer conjugates as a new platform for enzymatic biosensor and EBFC optimization. Poly(N-(3-dimethyl(ferrocenyl) methylammonium bromide)propyl acrylamide) (pFcAc) was grown directly from the surface of glucose oxidase (GOX) through atom-transfer radical polymerization. Utilization of the synthesized GOX-pFcAc conjugates led to a 24-fold increase in current generation efficiency and a 4-fold increase in EBFC power density compared to native GOX. GOX-pFcAc conjugates were further examined as working catalysts in carbon paper-based enzymatic biosensors, which provided reliable and selective glucose sensitivities and allowed a systematic analysis of sources of instability in enzyme-polymer conjugate-based biosensors and EBFCs. The knowledge gained through these studies and the in-depth characterization of an additional layer of optimization capacity using PBPE could potentially enhance the progress of enzymatic biosensor and EBFC development.

This thesis focuses on improved processing methods for enhanced mechanical properties in polymer nanocomposites, and controlled drug release in polymer based delivery systems. Supercritical carbon dioxide assisted mixing was successfully used in preparation of polypropylene/sepiolite and polypropylene/multiwall carbon nanotube nanocomposites. Relatively homogeneous dispersed and well separated nanofillers were obtained throughout the PP matrix. A better preservation of nanofiller lengths was observed in the scCO 2 assisted mixing. Mechanical property studies showed a marked increase in Young's modulus and tensile strength with the addition of nanofillers. More interestingly, techniques usually designed to achieve high quality PP nanocomposites, such as the use of masterbatches, maleic anhydride grafted polypropylene compatibilizers or polymer coated MWNTs are not needed to achieve equivalent mechanical properties with scCO2 assisted mixing. ScCO2 was also used as a foaming technique to modify the traditional cured poly(ethyl methacrylate/tetrahydrofurfuryl methacrylate) system for a controlled release of chlorhexidine. Highly porous structures were produced and chlorhexidine released from scCO2 foamed samples was more than 3 times higher than traditionally cured samples. By altering the processing conditions, such as CO2 saturation time and depressurization time the CX release rate was altered. Finally, the electrospinning method was combined with the layering encapsulation technique in order to enable the incorporation of water-soluble drugs in poly(lactic-co-glycolic acid) fibres for biomedical applications. Water-soluble drug, Rhodamine 6G or protein bovine serum albumin, loaded calcium carbonate microparticles were successfully incorporated in PLGA fibres and a bead and string structured composite fibres.

Este trabalho estuda a influência do carbonato de cálcio (CaCO3) nas propriedades mecânicas e na formação da fase cristalina beta do polipropileno (PP). Com o intuito de produzir amostras para o estudo, foi feita uma análise preliminar sobre o enxerto do anidrido maléico no polipropileno, porque este material graftizado (PP-g-MA) contribui significativamente em blendas e compósitos ao melhorar a adesão superficial entre o PP e o CaCO3. Foram estudados dois métodos de obtenção deste produto (PP-g-MA) utilizando-se peróxido orgânico e os produtos obtidos foram caracterizados e comparados. Apesar dos resultados das análises feitas por calorimetria diferencial exploratória (DSC), análise termogravimétrica (TGA), microscopia eletrônica de varredura (MEV) e espectroscopia de energia dispersiva (EDS) indicarem importantes diferenças entre os dois métodos, a análise por espectroscopia no infravermelho (FTIR) trouxe conclusões sobre a eficácia dos métodos de graftização. Duas séries de compósitos a base de PP contendo CaCO3 foram produzidos por mistura intensiva em fusão (misturador Drais), uma contendo PP-g-MA e a outra sem. Quatro tipos de CaCO3 foram utilizados, diâmetros de 0,9 µm, 2,5 µm e 3 µm, sendo que o CaCO3 0,9 µm apresentou-se com superfície tratada e não-tratada. A concentração de CaCO3 foi mantida em 5% e a de PP-g-MA em 5% quando presente. Os compósitos foram submetidos a testes de resistência à tração, módulo na flexão e resistência ao impacto em duas temperaturas. As amostras contendo menores tamanhos de partículas de CaCO3 e PP-g-MA apresentaram melhora sinérgica na resistência mecânica, em que aumentos da resistência a impacto e da resistência a flexão foram observados. A análise da fase cristalina beta nestas amostras foi feita utilizando-se DSC e difratometria de raios-x. Também foi analisada a influência da adesão superficial entre a carga e a matriz de PP, quanto maior a adesão superficial e menor o tamanho de partícula do CaCO3, maior a formação da fase cristalina beta, o que contribuiu para a sinergia entre todas as propriedades mecânicas avaliadas neste trabalho. / This study aimed at improving the comprehension of the influence of calcium carbonate (CaCO3) in the formation of the beta crystalline phase of polypropylene (PP), as well as the changes in the mechanical properties of this polymer. A preliminary analysis of the grafting of the maleic anhydride in the polypropylene was carried out in order to produce specimens for the study, owing to the fact that this grafted polypropylene (PP-g-MA) contributes substantially to change the polarity of the polymer and therefore, enhance the superficial adhesion between PP and CaCO3. Two grafting methods using organic peroxide were studied. The grafted copolymers were analyzed by DSC, TGA, SEM, EDS, and FTIR. Two series of PP composites containing CaCO3 were produced by intensive melt mixing (Drais mixer), one of them having MA-g-PP. Four types of CaCO3 were used, which diameters were 0.9 µm, 2.5 µm and 3 µm, though the CaCO3 0.9 µm was surface-treated and non-treated. The concentration of CaCO3 was maintained at 5% and PP-g-MA at 5 % also, when present. The composites were tested for tensile strength, flexural modulus and impact strength (at two temperatures). Samples containing smaller particle sized CaCO3 and PP-g-MA showed synergistic improvement in the mechanical strength, and increases in the impact resistance and flexural strength were observed. Analysis of the beta crystal phase in these samples was performed using DSC and x-ray diffractometry. The influence of superficial adhesion between CaCO3 and PP was also analyzed, higher concentration of the beta crystalline phase was observed for better surface adhesion and smaller CaCO3 particle size, which contributed to the synergy between all the mechanical properties evaluated in this work.

The food packaging industry is a £300bn global industry growing at a rate of 12% per year and increasingly favouring polymer or polymer-based materials. This generates 58m tonnes of "plastic" packaging waste annually in the EU and poses significant challenges for management given existing legislative constraints and increasing concerns surrounding the environmental impacts. The government, consumers, food retailers and pressure groups are all driving the demand for biodegradable packaging from renewable resources that can be disposed of with reduced impacts to the environment. Green Peace has devised a pyramid classification system of "Poisonous Plastics", which ranks plastics in terms of their harmfulness to the environment. They are campaigning against the use of oil-based materials and advocating the take up of biodegradable materials. The market for biodegradable food packaging is expanding rapidly but is still in its early stages of development and has not reached a critical mass to achieve significant market penetration. This is predominantly due to a lack of suitable materials that meet all environmental, functional and economical requirements. Whilst the long-term solution requires continued efforts in materials research and development, in the shorter term, changing working practices can abate the environmental impact of the industry. This research project tackled the challenge of environmental packaging from several directions: A novel starch-based material was developed that would fill the current gap in the food packaging market and facilitate recovery of the used materials by home composting. Using the sponsoring organisation as a case study, it was proved that by changing working practices by increasing rework and re-processing waste material for use in lower grade applications, both manufacturing costs and environmental impact can be reduced, thus benefiting both industry and the environment. A Life Cycle Assessment of selected biopolymers and oil-based polymers confirmed Green Peace's damning view of PVC and highlighted the need to develop biopolymers further. A domestic composting study of a range of commercially available "biodegradable" polymer materials revealed that a number of biodegradable packaging materials may typically biodegrade well in industrial high-temperature composting systems but fail to biodegrade under a low-temperature home composting environment and thus alerted the potential pitfall in waste management of some biodegradable polymers.

A solid breaker is used to reduce the viscosity of the gel at pH range of 4-5 for in-situ gelled acids with Zr4 cross-linkers utilize. However, the literature survey confirmed that solid breakers caused a premature reduction in the fluid viscosity resulting in a less than desirable productivity. Therefore, an effective liquid breaker that is based on tetrafluoroboric acid was developed. This study was conducted to evaluate this new breaker system under the following conditions: breaker concentration (0-200 ppm), and acid injection rate (0.5-10 cm3/min). The major findings from the performed viscosity measurements and single coreflood experiments can be summarized as follows: the crosslinking of the polymer occurred at a pH value of 1.8. At a pH of less than 2, doubling the breaker concentration did not affect the viscosity of the acid. However, at a pH of greater than 2, the viscosity of acid was reduced by 30 percent. At a breaker concentration of 0 ppm, the appearance of Zr in the core effluent sample was delayed by 0.25 PV compared to the reaction product, while at 100 ppm, Zr was delayed by 0.75 PV. At 200 ppm breaker, no Zr ions were detected in the effluent samples. Additionally, it was observed that as the breaker concentration increased, more Zr remained inside the core, as ZrF4, which is water-insoluble. Increasing the breaker concentration from 100 to 200 ppm reduced the final normalized pressure drop by 50 percent at injection rate of 2.5 cm3/min. Permeability reduction due to gel was reduced by increasing the acid injection rate.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Este trabalho teve como objetivo sintetizar catalisadores metÃlicos de ferro suportados em carbono ativado a base de polÃmeros para sÃntese de Fischer-Tropsch. A preparaÃÃo dos catalisadores foi realizada pelo mÃtodo de impregnaÃÃo a umidade incipiente, utilizando soluÃÃo aquosa de nitrato de ferro nonahidratado para obtenÃÃo de amostras com, aproximadamente, 55% de ferro. Duas amostras foram preparadas (FeCP1 e FeCP2) e caracterizadas por fluorescÃncia de raios-X por energia dispersiva (EDXRF), difraÃÃo de raios-X (DRX), medidas de fisissorÃÃo de nitrogÃnio, espectroscopia fotoeletrÃnica de raio-X (XPS), microscopia eletrÃnica de varredura (SEM-EDS) e reduÃÃo à temperatura programada (TPR). As amostras foram submetidas tambÃm a testes catalÃticos, utilizando-se diferentes condiÃÃes de temperatura (513, 528 e 543 K), pressÃo (20, 25 e 30 atm) e razÃo molar H2:CO de 1 e 0,5. Os dados de EDXRF evidenciaram considerÃvel diferenÃa no teor de metal impregnado entre os dois catalisadores; o FeCP2 apresentou teor prÃximo ao esperado enquanto o catalisador FeCP1 ficou aquÃm do desejado. Os difratogramas obtidos por DRX mostraram um maior grau de cristalinidade da amostra FeCP2, enquanto FeCP1 e os dois suportes (CP1 e CP2) apresentaram-se como semi-cristalinos. Para o catalisador FeCP2, apresentaram-se duas fases ativas presentes, α-Fe2O3 e γ-Fe2O3; jà no FeCP1, hà apenas α-Fe2O3. A anÃlise das caracterÃsticas texturais revelou que, apÃs a introduÃÃo metÃlica no suporte, houve decrÃscimo nos valores de Ãrea especÃfica, volume de poros e diÃmetro de poros, sendo mais perceptÃvel para o catalisador FeCP2. As curvas de XPS expuseram os grupos funcionais oxigenados presentes na superfÃcie dos suportes, bem como a presenÃa do Fe+3 como fase ativa predominante em ambos os catalisadores. O espectro de ambos os catalisadores apresentou tambÃm um pico satÃlite que sugere a presenÃa de um outro estado de valÃncia do ferro semelhante ao que se tem no carbeto de ferro. As imagens obtidas por SEM exibiram forma e superfÃcie irregulares, sendo as partÃculas presentes no FeCP2 maiores que a do FeCP1 devido a sua cristalinidade. Os dados de EDS demonstraram que, aproximadamente, metade do percentual de ferro presente no catalisador encontra-se na superfÃcie. Pode-se inferir tambÃm por essa anÃlise, utilizando-se seu espectro, a presenÃa de carbeto de ferro na superfÃcie do catalisador. As curvas de TPR evidenciaram uma maior estabilidade do catalisador FeCP2 mediante o FeCP1, por este ter apresentado trÃs etapas de reduÃÃo do Ãxido de ferro e nÃo duas, como apresentada para aquele Ãltimo. O teste catalÃtico expÃs a melhor eficiÃncia do catalisador FeCP2 para a produÃÃo de hidrocarbonetos na faixa de C5-C9, para as mesmas condiÃÃes de temperatura, pressÃo e razÃo molar. Entretanto, a diminuiÃÃo da razÃo molar desfavoreceu a obtenÃÃo de hidrocarbonetos pesados. / The aim of this work was to synthesize iron catalysts supported on polymer-based activated carbons, for the Fischer-Tropsch synthesis. The preparation of the catalysts was performed by incipient wetness impregnation method using an aqueous solution of iron nitrate nonahydrate to obtain samples with approximately 55 % of iron. Two samples were prepared (FeCP1 and FECP2) and characterized by energy dispersive X-ray fluorescence (EDXRF), X-ray diffraction (XRD), nitrogen adsorption measurements, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM-EDS) and temperature-programmed reduction (TPR). The samples were also submitted to catalytic tests using different conditions of temperature (513, 528 and 543 K), pressure (20, 25 and 30 atm), and H2:CO molar ratio of 1 and 0.5. EDXRF data showed considerable difference in content of impregnated metal for both catalysts. FeCP2 exhibited an iron load close to the value expected while FeCP1 presented an iron load significantly lower than expected. XRD patterns showed a higher degree of crystallinity of the sample FeCP2, whereas FeCP1 and both supports used (CP1 and CP2) were found to be semi-crystalline. FeCP2 catalyst presented two active phases, α-Fe2O3 and γ-Fe2O3, while FeCP1 showed only one phase, α-Fe2O3. The analysis of the textural characteristics revealed a decrease in the values of the specific area, pore volume and pore diameter after the introduction of the metal into the support, which was more noticeable with the FeCP2 catalyst. XPS patterns indicated oxygen functional groups on the support surface and the presence of Fe+3 as the predominant active phase on both catalysts. The spectrum of both catalysts also showed a satellite peak which shows the presence of another valence state similar to the iron carbide. Images obtained by SEM revealed irregular shape and surface, being the particles present in FeCP2 greater than those on FeCP1 due to the crystallinity of the former. EDS data showed that approximately half of the iron percentage present in the catalyst bulk is on the surface. The presence of iron carbide on the catalyst surface can be inferred by using this spectrum analysis too. TPR graphics demonstrated a higher stability of the FeCP2, due to the three-step reduction of iron oxide instead of two as shown for the FeCP1. According to the results of the catalytic tests FeCP2 exhibited a better efficiency for the production of hydrocarbons in the C5-C9 range, for the same conditions of temperature, pressure and molar ratio. However, the decrease in the molar ratio disfavors the production of heavy hydrocarbons.