Journal Menu► ▼ Journal Menu
Journal Browser► ▼ Journal Browser
Special Issue "Recent Advances in Co–Catalysts: From Catalyst Preparation to Catalytic Performance"
A special issue of Catalysts (ISSN 2073-4344).
Deadline for manuscript submissions: 15 December 2019.
Dr. John Vakros Website E-Mail
Department of Chemistry, University of Patras, Patras 26504, Greece
Interests: preparation, characterization and testing of supported catalysts, Environmental friendly processes, Advanced oxidation processes, biochar applications, acid - base behavior of nanoparticles, potentiometric mass titrations, metal support interactions
In our days Cobalt catalysts are very attractive because they exhibit a lot of advantages like low cost and high activity in a significant variety of different applications. Co– catalysts are among the most active catalysts for Fischer–Tropsch synthesis and they promote the catalytic activity of the hydrodesulfurization catalysts. Also they found other significant applications in environmental protection like oxidation of volatile organic compounds, VOC, persulfate activator, ammonia synthesis, electrocatalysis and many more. Co–catalysts are active, stable and exhibit significant oxidation – reduction activity, as the Co can be found either as Co(II) or Co(III). Also many molecules can interact with cobalt supported phase by co – ordination due to partially filled d-orbital. Co– catalysts can be supported in almost all the inorganic supports like alumina, titania, zeolites etc. The cobalt oxide phase can be stabilized onto the surface of the support due to variable interactions between support and cobalt phase. These interactions are crucial for catalytic activity and can be regulated by proper selection of the preparation parameters like the type of support, the Co loading, impregnation method and thermal conditions.
This Special Issue aims to cover recent progress and advances in the field of Co catalysts. This includes, but is not restricted to, the synthesis of Co–catalysts with different preparation methods, their catalytic performance in different catalytic processes in which the Co–catalyst are active and selective, the effect of preparation method in physicochemical characteristics of supported cobalt phase and the correlation between catalytic activity and their physicochemical characteristics. Finally, new catalytic applications of Co–catalysts are strongly welcoming.
Dr John Vakros
Manuscript Submission Information
Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.
Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Catalysts is an international peer-reviewed open access monthly journal published by MDPI.
Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.
- Supported catalysts
- Catalysts preparation,
- Physicochemical properties of supported catalysts
- Catalytic evaluation
- Fischer–Tropsch synthesis
The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.
Cobalt–alumina co-precipitated catalysts for green diesel production
George Kogkos, Ioannis Nikolopoulos, Crisanthi Andriopoulou, Eleana Kordouli, Kyriakos Bourikas, Alexis Lycourghiotis and Christos Kordulis
Abstract: The effect of activation (reduction) temperature and of cobalt loading on the physicochemical properties and the catalytic performance of cobalt-alumina catalysts for the transformation of triglycerides into green diesel has been studied. In this context, three catalysts containing 55 wt % Co were prepared by controlled co-precipitation method and reduced at three different temperatures (400, 500 and 600 oC). Two additional catalysts were, moreover, synthesized with different cobalt loadings (35 and 70 wt % Co). The latter catalysts were activated at the optimum reduction temperature (5000C). The catalysts were characterized using various techniques (nitrogen adsorption–desorption isotherms, XRD, TEM, H2-TPR, NH3-TPD, CO-adsorption) and evaluated in the transformation of sunflower oil and waste cooking oil into green diesel using a batch reactor working in a semi-batch mode. The catalytic tests were performed under solvent free conditions at 310oC, hydrogen pressure of 40 atm, hydrogen flow rate equal to 96ml/min, reactant volume to catalyst mass ratio equal to 100ml/1g and various reaction times up to 9h.
The analysis of the produced liquid phase showed the formation of n-alkanes (C11- C18) in the green diesel range as well as considerable amounts of intermediate acids and esters. The composition of the liquid phase and the kinetic curves indicated a reaction network similar to that reported for the nickel based catalysts. The catalyst containing 55 wt % Co which was activated at 500oC was proved to be the most active for both feeds. A conversion of sunflower oil equal to 100% and a composition of the liquid phase in green diesel equal to 71.2% were obtained over this catalyst for reaction time equal to 9h. The corresponding values for the transformation of waste cooking oil into green diesel were 100% and 51.3 indicating the feed effect. The catalytic behavior of the catalysts was rationalized using the results of their physicochemical characterization.