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Advancement in the Utilization of Biomass-Derived Heterogeneous Catalysts in Biodiesel Production  [PDF]
Nurudeen Ishola Mohammed, Nassereldeen Ahmed Kabbashi, Abass Olanrewaju Alade, Sarina Sulaiman
Green and Sustainable Chemistry (GSC) , 2018, DOI: 10.4236/gsc.2018.81006
Abstract: Solid oxide catalysts derived from various renewable sources have produced significant yield of methyl esters of enhanced purity. These materials are sourced for due to their advantages ranging from low cost, recoverability and reusability, environmental benign-ness, thermal stability and high quality product generation. For a possible greener production process, many researchers in literature reported the use of biomass-derived heterogeneous catalyst in biodiesel synthesis producing high quality pure product. The catalysts were majorly modified through simple physical cost effective and energy saving operations. This paper explores some of these bio-based heterogeneous catalyst used in biodiesel production via transesterification and esterification approach and their performance in FAME yield and conversion. The feedstock consideration which warrant the route selection, various approaches that are adopted in biodiesel production, performance of renewable heterogeneous catalyst and the measures that were adopted to enhance efficiency of the catalyst were considerably highlighted. It is observed that the prospects of organic-based solid catalyst in biodiesel development is a promising enterprise compared to the conventional methods utilizing homogeneous chemical catalyst, which generates wastewater requiring treatment before disposal and generates product that may cause engine malfunction. This review work aimed at providing detailed and up-to-date record of the trend in renewable catalyst development in biodiesel synthesis. This is expected to inform a suitable selection and reaction conditions in the development of biodiesel from the very many feed stocks.
Optimization Study in Biodiesel Production via Response Surface Methodology Using Dolomite as a Heterogeneous Catalyst  [PDF]
Regina C. R. Santos,R?mulo B. Vieira,Antoninho Valentini
Journal of Catalysts , 2014, DOI: 10.1155/2014/213607
Abstract: A carbonate mineral, dolomite, was used as a heterogeneous catalyst to produce methyl-esters from soybean oil. The samples were analyzed by XRF, TGA, XRD, TPD-CO2, and SEM. The calcination of dolomite at 800°C/1?h resulted in a highly active mixed metal oxides. In addition, the influence of the reaction variables such as the temperature, catalyst amount, and methanol/soybean oil molar ratio in methyl-ester production was optimized by the application of a central composite design in conjunction with the response surface methodology (RSM). The XRF analysis is carried out after the reuses procedure which shows that the deactivation process is mainly due to the selective calcium leaching. Overall, the calcined dolomite exhibited high catalytic activity at moderate operating conditions for biodiesel production. 1. Introduction The increase in the number of publications addressing the topic biodiesel in recent years is noticeable [1]. This is due to the environmental benefits that the biodiesel fuel provides [2]. Conventional biodiesel production is performed through a transesterification reaction of triglycerides with mono-alkyl alcohols (i.e., methanol and ethanol) [3]. Homogeneous alkaline catalysts have been widely used since the process produces high amount of methyl-esters in a short reaction time [4, 5]. In order to solve the problem related to the purification step, solid base catalysts have been considered as an alternative to homogeneous base catalysts [6, 7]. Occasionally, the synthesis processes of heterogeneous catalysts can contribute to an additional cost of the final product. However, the use of a simple, safe, and low cost heterogeneous catalyst for the biodiesel production reaction can be effective to an industrial application [8, 9]. Dolomite is a natural carbonate mineral typically represented by a stoichiometric chemical composition of CaMg(CO3)2 [10]. During the calcinations, the carbonate groups are decomposed generating their respective basic oxides (MgO and CaO) [11, 12]. The alkaline oxides CaO and MgO are frequently used as heterogeneous catalysts for biodiesel production [13–15]. Therefore, the solid dolomite catalyst, which is an environmentally acceptable material with high basicity and low cost, is possibly an efficient and promising alternative catalyst for biodiesel production. Several studies [11, 16–20] have reported the use of calcined and/or modified dolomite as a solid catalyst for biodiesel production; however the operating conditions involved a longer reaction time with high methanol/oil ratio and catalyst weight, none
Heterogeneous Tin Catalysts Applied to the Esterification and Transesterification Reactions  [PDF]
Márcio José da Silva,Abiney Lemos Cardoso
Journal of Catalysts , 2013, DOI: 10.1155/2013/510509
Abstract: The interest in the development of efficient and environmentally benign catalysts for esters synthesis has increased exponentially, mainly due to the demand for biodiesel. In general, fatty esters are used as bioadditive, cosmetic ingredients, polymers, and, more recently, biofuel. Nevertheless, most of the production processes use nonrecyclable and homogenous alkaline catalysts, which results in the reactors corrosion, large generation of effluents, and residues on the steps of separation and catalyst neutralization. Heterogeneous acid catalysts can answer these demands and are an environmentally benign alternative extensively explored. Remarkably, solid acid catalysts based on tin have been shown highly attractive for the biodiesel production, mainly via FFA esterification reactions. This review describes important features related to be the synthesis, stability to, and activity of heterogeneous tin catalysts in biodiesel production reactions. 1. Introduction The recent demand by alternative energy sources has made the biodiesel production a concern worldwide. Biodiesel is a renewable, biodegradable, and less polluting fuel than mineral diesel. It consists of ethyl (FAEE) or methyl esters of fatty acids (FAME), which are obtained from the triglycerides (TG) transesterification reactions present in vegetal oil (Figure 1), such as showed in Figure 1 [1]. Figure 1: Transesterification of triglycerides with methyl or ethyl alcohol. Currently, most of the processes used for biodiesel production from the vegetable oils transesterification operating under homogeneous alkaline catalysis conditions (i.e., NaOH, KOH, or NaOCH3) [1]. However, if a high content of FFA is present, homogeneous acid catalysts (i.e., H2SO4) are commonly applied on the steps of preesterification [1]. Both processes result in a large generation of wastewaters, residues, and salts formed during the catalyst neutralization and products recovery. Currently, the greater part of the biodiesel consumed is produced by transesterification of expensive edible vegetable oils, which are responsible for 65% of the final price [2]. Alternative routes for the production of biodiesel where inexpensive feedstock such as animal fats, waste frying, and highly acid vegetable oil are an attractive option [3]. Nevertheless, these low cost raw materials are incompatible with alkaline catalysts due the formation of soaps, which hinders the separation of the FAME or FAEE from the glycerol, reducing consequently the biodiesel yields [4]. For these reasons, developing active catalysts for the FFA esterification
Deactivation Processes, Regeneration Conditions and Reusability Performance of CaO or MgO Based Catalysts Used for Biodiesel Production—A Review  [PDF]
Nombamba Oueda, Yvonne L. Bonzi-Coulibaly, Igor W. K. Ouédraogo
Materials Sciences and Applications (MSA) , 2017, DOI: 10.4236/msa.2017.81007
Abstract: The activity of a catalyst in transestrification reaction usually declines with repeated uses and this limits the possibility to use it many times. This paper presents a review of various techniques used to evaluate the activity changes, the recycling processes for calcium and magnesium oxides based heterogeneous catalysts for biodiesel production. The activity of calcium and magnesium oxides based catalysts declines due to leaching, surface or active sites poisoning by reactant or product molecules and modification of physical aspects. Physico-chemical methods (AAS, BET, CO2-TPD, EDS, FTIR, ICP-AES, SEM, TG/DTA and XRD were used to check the catalyst modification and to confirm the deactivation. When separated from the reaction mixture by filtration, the catalyst could be reused without any treatment or recycled by washing, drying or/and recalcination. Between various recycling processes for calcium and magnesium oxides based catalysts, mixed oxides showed less leaching and performed FAME or FAEE yield >90% with reusability.
Use of ionic liquids in biodiesel production: a review
Andreani, L.;Rocha, J. D.;
Brazilian Journal of Chemical Engineering , 2012, DOI: 10.1590/S0104-66322012000100001
Abstract: this paper discusses the feasibility of the use of ionic liquids as catalysts in the biodiesel production field, describing some studies already published in the literature on this theme. ionic liquids are regarded as a new generation of catalysts in the chemical industry, with several uses in different commercial segments. however only a few publications involving this topic can be found in the literature addressing the manufacture of biodiesel from vegetable oils or animal fats. through the analysis of the data generated in the studies reviewed, it is possible to affirm that ionic liquids present great potential as catalysts for biodiesel production, but there are some challenges to be faced, such as the production of ionic liquids with low cost, easy recovery and with the possibility of reutilization of the catalyst for several cycles.
Búsqueda de Catalizadores Sólidos Básicos para la Producción de Biodiesel Searching for Solid base Catalysts for Biodiesel Production  [cached]
Mónica Becerra,Aristóbulo Centeno,Sonia A Giraldo
Información Tecnológica , 2010,
Abstract: Esta investigación tuvo como objetivo la búsqueda de catalizadores sólidos básicos activos y estables que contribuyan al desarrollo de sistemas de reacción heterogéneos para producción limpia de biodiesel. Se prepararon y evaluaron en la transesterificación de triacetina tres tipos de catalizadores: CaO, γ-Al2O3 modificada con Na y K, y MgO modificado con Na, Li, Rb y Cs. Se analizó la influencia de las propiedades texturales, tipo y cantidad de metal impregnado y la activación con N2, sobre la basicidad y el comportamiento catalítico. Se estudió la estabilidad de estos materiales mediante absorción atómica y reusos consecutivos. Los resultados mostraron que la impregnación de metales no conduce a la formación de sólidos estables, ya que éstos se lixivian en el medio de reacción. El CaO mantuvo una elevada actividad catalítica durante cinco ciclos de reacción convirtiéndolo en un material con alto potencial para ser utilizado en un proceso industrial. This work aimed to find active and stable solid base catalysts for clean biodiesel production using heterogeneous reaction systems. Three types of catalysts were synthesized and evaluated in the transesterification of triacetin: CaO, γ-Al2O3 modified with Na and K, and MgO modified with Na, Li, Rb and Cs. The influence of the textural proprieties, the type and amount of alkali metal impregnated and the activation with N2 on the basicity and the catalytic behavior were analyzed. Stability of catalysts was analyzed using atomic absorption measurements and reuse reactions. Results showed that metal impregnation does not lead to the formation of stable solids, because they present lixiviation in the reaction system. The CaO maintained a high catalytic activity during five reaction cycles showing its high potential of its use in an industrial process.
Biodiesel: vis?o crítica do status atual e perspectivas na academia e na indústria
Dabdoub, Miguel J.;Bronzel, Jo?o L.;Rampin, Márcia A.;
Química Nova , 2009, DOI: 10.1590/S0100-40422009000300021
Abstract: this article presents a bibliographic review of research carried out on different alternative processes for biodiesel production. the supercritical and subcritical (non catalytic) reaction conditions, the use of solid basic, solid acid and other heterogeneous catalysts, including the use of immobilized enzymes and whole-cell catalysts are also critically compared with the traditional homogeneous alkaline or acid catalysts that are common on industrial applications. advantages and limitations of all these processes for the transference from the laboratory to the industry are discussed. a correlation of the chemical composition with the quality parameters of the produced biodiesel is done with aim to stablish adequate procedures for the right selection of the raw-material. castor bean oil is used as an example of inappropriate oil in order to produce a b100 that fulfill all the international physico-chemical quality standards. in this article are presented research results to adequate the values of viscosity, density and iodine number of the castor and soybean biodiesel to the international standard limits by means blending these both biodiesels at the right ratio.
Synthesis of Jatropha Oil based Biodiesel Using Environmentally Friendly Catalyst and Their Blending Studies with Diesel
Energy and Power , 2013, DOI: 10.5923/j.ep.20130301.02
Abstract: Jatropha oil is readily available as one of the cheapest non-food feedstock in India. In this work, we would like to explore the use of Zirconium based heterogeneous catalysts to synthesis Jatropha oil biodiesel ((JBD) and to take advantages of the solid nature as well as reusability of the environmentally friendly heterogeneous catalyst. In order to compare JBD was also synthesized using conventional sodium metoxide (NaOMe homogenous catalyst). Best yield was obtained using heterogeneous catalyst (ZH3). Synthesized JBD by both homogenous and heterogeneous catalysts were characterized by FTIR, and Diesel Fuel Properties like viscosity and density. Viscosities of synthesized all JBD were in agreement with ASTM D-6751 (100%-BD) and ASTM D-975 (100%-Diesel). In this study, Blending studies of Jatropha biodiesel-JBD (5 %) with diesel was also carried out and diesel fuel properties like viscosity, density, pour point and flash point were also investigated. Except density of blended mixture, all other fuel properties studied are in agreement with ASTM D-975 (100%-Diesel). 5% JBD Blend have nearly same physical properties as that of petro-diesel which demonstrates that it would be commercially viable to use in the field. This study will help biodiesel producer to be competitive in production of Jatropha based biodiesel, using heterogeneous catalyst and work up process would be easied and reusecatalyst. Thus it provides the economic pathway for the synthesis of eco-friendly biodiesel.
Búsqueda de Catalizadores Sólidos Básicos para la Producción de Biodiesel
Becerra,Mónica; Centeno,Aristóbulo; Giraldo,Sonia A;
Información tecnológica , 2010, DOI: 10.4067/S0718-07642010000400008
Abstract: this work aimed to find active and stable solid base catalysts for clean biodiesel production using heterogeneous reaction systems. three types of catalysts were synthesized and evaluated in the transesterification of triacetin: cao, γ-al2o3 modified with na and k, and mgo modified with na, li, rb and cs. the influence of the textural proprieties, the type and amount of alkali metal impregnated and the activation with n2 on the basicity and the catalytic behavior were analyzed. stability of catalysts was analyzed using atomic absorption measurements and reuse reactions. results showed that metal impregnation does not lead to the formation of stable solids, because they present lixiviation in the reaction system. the cao maintained a high catalytic activity during five reaction cycles showing its high potential of its use in an industrial process.
Solid Catalysts and theirs Application in Biodiesel Production  [cached]
Ramli Mat,Rubyatul Adawiyah Samsudin,Mahadhir Mohamed,Anwar Johari
Bulletin of Chemical Reaction Engineering & Catalysis , 2012, DOI: 10.9767/bcrec.7.2.3047.142-149
Abstract: The reduction of oil resources and increasing petroleum price has led to the search for alternative fuel from renewable resources such as biodiesel. Currently biodiesel is produced from vegetable oil using liquid catalysts. Replacement of liquid catalysts with solid catalysts would greatly solve the problems associated with expensive separation methods and corrosion problems, yielding to a cleaner product and greatly decreasing the cost of biodiesel production. In this paper, the development of solid catalysts and its catalytic activity are reviewed. Solid catalysts are able to perform trans-esterification and esterification reactions simultaneously and able to convert low quality oils with high amount of Free Fatty Acids. The parameters that effect the production of biodiesel are discussed in this paper. Copyright 2012 by BCREC UNDIP. All rights reserved Received: 6th April 2012, Revised: 24th October 2012, Accepted: 24th October 2012 [How to Cite: R. Mat, R.A. Samsudin, M. Mohamed, A. Johari, (2012). Solid Catalysts and Their Application in Biodiesel Production. Bulletin of Chemical Reaction Engineering & Catalysis, 7(2): 142-149. doi:10.9767/bcrec.7.2.3047.142-149] [How to Link / DOI: http://dx.doi.org/10.9767/bcrec.7.2.3047.142-149 ] | View in
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