Use of Soybean Oil like as Fuel for Diesel Cycle Engine

Abstract

Diesel fuel price is rapidly increasing burdening the agricultural production costs. Additionally, diesel is contributing to a significant amount of life cycle greenhouse gases emissions. Strategically, using agricultural feedstock, such as soybean oil, will reduce fossil fuel price volatility and carbon footprint from agriculture. Although cheaper than biodiesel, use of pure soybean oil has shown to damage a regular diesel engine because of its high viscosity. In this work, a novel technology was developed and tested to overcome this problem by fueling a direct injection Diesel engine with refined soybean oil (edible oil) heated by engine coolant and exhaust gases. Thermal efficiency, air/fuel ratio, fuel injection timing, exhaust temperature and exhaust emissions were evaluated. The major finding of this study was to identify the feasibility of running a modified engine properly with heated soybean oil. The results showed that soybean oil use reduces emissions of nitrogen oxides, but contributes both to lower thermal efficiency and higher emissions of other products such as carbon monoxide and particulate matter compared to fossil diesel. Despite these negative results, solutions to reduce pollutant emissions are feasible.

1H NMR and UV-Vis as Analytical Techniques to Evaluate Biodiesel Conversion and Oxidative Stability

“…The quality of the biodiesel physicochemical properties is essential for its application as fuel in cycle diesel engines [11,[36][37][38]. Notably, density and viscosity can impact combustion efficiency because the flow resistance reduces the fluid motion and atomization process occurring in injectors.…”

“…In Brazil, the current mandatory biodiesel percentage in diesel is 12% (B12), with projections of a 1% annual increase until 2025 [9]. However, despite the importance of biodiesel for the Brazilian energy matrix, its application as biofuel in diesel cycle engines is still connected to questions related to the physicochemical properties that can interfere with biodiesel performance, such as a low ester content and low oxidative stability [3,[10][11][12][13][14].…”

“…Technical problems have been reported by use of mixtures with high vegetable oil content, such as lower thermal efficiency, higher emissions of carbon monoxide (CO) and particulate matter, fouling on the injectors, carbonaceous deposits near the nozzles, and engine performance and durability reduction. Some researchers attribute these problems to the combined effects of density, viscosity, free fatty acids, phospholipids, sterols, water, odorants, and other impurities of vegetal oils [11].…”

“…As the low oxidative stability of biodiesel affects its quality, this phenomenon has great importance in its production chain. Some problems attributed to the oxidized biodiesel are: (1) incompatibility with automotive parts; (2) corrosion caused by the presence of water and free fatty acids; (3) incompatibility with copper, aluminum, zinc, brass, and bronze; (4) swelling of nitrile rubber; (5) plugging of fuel lines; and (6) fouling on surfaces in contact with the biofuel [11,[15][16][17][18].…”