Abstract
Catalysts based on zirconia- and alumina-supported tungsten oxides (15 wt % W) with a small loading of platinum (0.3 wt % Pt) were selected to study the influence of the reduction temperature and the nature of the support on the hydroisomerization of n-dodecane. The reduction temperature has a major influence on metal dispersion, which impacts the catalytic activity. In addition, alumina and zirconia supports show different catalytic properties (mainly acid site strength and surface area), which play an important role in the conversion. The NH3-TPD profiles indicate that the acidity in alumina-based catalysts is clearly higher than that in their zirconia counterparts; this acidity can be attributed to a stronger interaction of the WOx species with alumina. The PtW/Al catalyst was found to exhibit the best catalytic performance for the hydroisomerization of n-dodecane based on its higher acidity, which was ascribed to its larger surface area relative to that of its zirconia counterparts. The selectivity for different hydrocarbons (C7–10, C11 and i-C12) was very similar for all the catalysts studied, with branched C12 hydrocarbons being the main products obtained (~80%). The temperature of 350 °C was clearly the best reduction temperature for all the catalysts studied in a trickled-bed-mode reactor.
Highlights
Renewable fuels are increasingly in demand due to the high consumption of fossil fuel resources, whose use produces global warming, and their reserves are limited and concentrated in some countries suffering conflicts
Considering the results published in the literature for hydroisomerization, the aim of this work is to study the influence of the reduction temperature and the support nature in the hydroisomerization of n-dodecane to improve the lineal alkane fuels mentioned before and produce a suitable green diesel
A decrease in the BET surface area is observed in this case
Summary
Renewable fuels are increasingly in demand due to the high consumption of fossil fuel resources (petroleum and natural gas), whose use produces global warming, and their reserves are limited and concentrated in some countries suffering conflicts In this context, biofuels have attracted much attention as renewable fuels [1], having environmental benefits and being necessary for the sustainable development of society [2]. A better alternative is the production of green diesel by catalytic hydroprocessing of triglycerides or carboxylic esters to generate hydrocarbons (hydrotreatment of vegetable oils, nonedible oils or fats, HVO). Another way to obtain green diesel is Fischer–Tropsch synthesis, which produces known GTL (gas to liquids) diesel. Green diesel stands out for its high cetane number, low cloud point, absence of aromatic hydrocarbons and sulfur, and lower emissions of greenhouse gases [4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
