# Temperature Dependence of Density and Viscosity of Biobutanol-Gasoline Blends  
[PERSON]  
1 Department of Technology and Automobile Transport, Mendel University in Brno, Zemedelska 1665/1, 613 00 Brno, Czech Republic; [EMAIL_ADDRESS] (D.T. ); [EMAIL_ADDRESS] (A.P. )1  
[PERSON]  
1 Department of Technology and Automobile Transport, Mendel University in Brno, Zemedelska 1665/1, 613 00 Brno, Czech Republic; [EMAIL_ADDRESS] (D.T. ); [EMAIL_ADDRESS] (A.P. )1  
[PERSON]  
2 Department of Biological and Agricultural Engineering, Louisiana State University Agricultural Center, 149 E. B. Doran Building, Baton Rouge, LA 70803-4505, USA; [PERSON]@agcenter.lsu.edu2  
[PERSON]  
3 College of Technology, University of Bameada, Bameada, P.O. Box 39, Bambili, Cameroon; [EMAIL_ADDRESS]  
[PERSON]  
4 Department of Quality and Safety of Industrial Products, Cracow University of Economics, Kakowicka 27, 31-510 Krakow, Poland; [EMAIL_ADDRESS]  
[PERSON]  
1 Department of Technology and Automobile Transport, Mendel University in Brno, Zemedelska 1665/1, 613 00 Brno, Czech Republic; [EMAIL_ADDRESS] (D.T. ); [EMAIL_ADDRESS] (A.P. )1  
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A promising solution seems to be the processing of biofuels. Two of the main advantages of using biofuels is its good availability and the abundance of local raw materials for production--directly at the place of consumption. Biofuels can replace petroleum fuels mainly in the transportation sector and, in many cases, without the replacement of the existing powertrain design. Of the various biofuels, biobutanol (especially produced from lignocellulosic raw materials [7]) seems to be one of the most appealing because biobutanol has attractive properties such as a higher heating value/specific energy, cetane number, hydrophobicity, and low vapour pressure [8; 9]. Furthermore, it is less corrosive and volatile [10]. Currently, in the US and Europe, biofuels are blended with commonly used fuels, referred to as E5, E7, and E10 per Directive 2008/50/EC in Europe. The former and latter express the type of fuel used as the bio-component (bioethanol or fatty acid methyl ester, respectively) as well as the quantity of the biofuel (5, 7, or 10 vol.%, respectively) that have been incorporated into the fossil fuel. Biobutanol can be produced similarly to bioethanol by fermentation of the directly fermentable simple sugars, called the ABE (Acetone-Butanol-Ethanol) process under the action of the microorganism (_Clostridium acetobutylicum_) [11]. Starch crops (cereals, maize, and potatoes) and molasses from the sugar came or sugar beet are the traditional raw materials used to produce biobutanol [12; 13]. On the other hand, microalgae strains are also gaining attention as an advanced energy feedstock for biofuel production [14; 15]. Due to the similar properties to common use fuels, it is possible to add larger amounts of biobutanol into a fuel, which would result in a bigger fossil fuel savings. Although many science papers have been published about biobutanol as a promising biofuel, (e.g., [16; 17; 18]) only a couple of them have investigated the temperature effect on the rheological properties (kinematic and dynamic viscosity) of the fuel, and only for bioethanol [19]. The temperature dependent properties are crucial for understanding the performance of the fuel and, subsequently, the engine over a given period of time [20; 21].