World energy demand is expected to increase due to the expanding urbanization, better living standards and increasing population. At a time when society is becoming increasingly aware of the declining reserves of fossil fuels beside the environmental concerns, it has become apparent that biodiesel is destined to make a substantial contribution to the future energy demands of the domestic and industrial economies. There are different potential feedstocks for biodiesel production. Non-edible vegetable oils which are known as the second generation feedstocks can be considered as promising substitutions for traditional edible food crops for the production of biodiesel. The use of non-edible plant oils is very significant because of the tremendous demand for edible oils as food source. Moreover, edible oils’ feedstock costs are far expensive to be used as fuel. Therefore, production of biodiesel from non-edible oils is an effective way to overcome all the associated problems with edible oils. However, the potential of converting non-edible oil into biodiesel must be well examined. This is because physical and chemical properties of biodiesel produced from any feedstock must comply with the limits of ASTM and DIN EN specifications for biodiesel fuels. This paper introduces non-edible vegetable oils to be used as biodiesel feedstocks. Several aspects related to these feedstocks have been reviewed from various recent publications. These aspects include overview of non-edible oil resources, advantages of non-edible oils, problems in exploitation of non-edible oils, fatty acid composition profiles (FAC) of various non-edible oils, oil extraction techniques, technologies of biodiesel production from non-edible oils, biodiesel standards and characterization, properties and characteristic of non-edible biodiesel and engine performance and emission production. As a conclusion, it has been found that there is a huge chance to produce biodiesel from non-edible oil sources and therefore it can boost the future production of biodiesel.

Non-edible vegetable oils: A critical evaluation of oil extraction, fatty acid compositions, biodiesel production, characteristics, engine performance and emissions production

Natural-gas fueled spark-ignition (SI) and compression-ignition (CI) engine performance and emissions

Production and comparison of fuel properties, engine performance, and emission characteristics of biodiesel from various non-edible vegetable oils: A review

The use of inedible vegetable oils as an alternative fuel for diesel engine is accelerated by the energy crisis due to depletion of resources and increased environmental problems including the great need for edible oil as food and the reduction of biodiesel production cost, etc. Of a lot of inedible vegetable oils which can be exploited for substitute fuel as diesel fuel, seven vegetable oils, i.e., jatropha, karanja, mahua, linseed, rubber seed, cottonseed and neem oils were selected for discussion in this review paper. The application of jatropha oil as a liquid fuel for CI engine can be classified with neat jatropha oil, engine modifications such as preheating, and dual fuelling, and fuel modifications such as jatropha oil blends with other fuels, mostly with diesel fuel, biodiesel, biodiesel blends and degumming. Therefore, jatropha oil is a leading candidate for the commercialization of non-edible vegetable oils. There exists a big difference in the fuel properties of seven inedible vegetable oils and its biodiesels considered in this review. It is clear from this review that biodiesel generally causes an increase in NOx emission and a decrease in HC, CO and PM emissions compared to diesel. It was reported that a diesel engine without any modification would run successfully on a blend of 20% vegetable oil and 80% diesel fuel without damage to engine parts. This trend can be applied to the biodiesel blends even though particular biodiesel shows 40% blend. In addition, the blends of biodiesel and diesel can replace the diesel fuel up to 10% by volume for running common rail direct injection system without any durability problems.

Inedible vegetable oils and their derivatives for alternative diesel fuels in CI engines: A review

A review on natural gas/diesel dual fuel combustion, emissions and performance

Effect of variation in LPG composition on emissions and performance in a dual fuel diesel engine

Effect of exhaust gas recirculation on diesel engine nitrogen oxide reduction operating with jojoba methyl ester.

Improving the performance of dual fuel engines running on natural gas/LPG by using pilot fuel derived from jojoba seeds

Experimental study on diesel engine nitrogen oxide reduction running with jojoba methyl ester by exhaust gas recirculation

Improving the performance and emission characteristics of a diesel engine fueled by jojoba methyl ester-diesel-ethanol ternary blends

H.E. Saleh

Papers

Effect of variation in LPG composition on emissions and performance in a dual fuel diesel engine

Effect of exhaust gas recirculation on diesel engine nitrogen oxide reduction operating with jojoba methyl ester.

Improving the performance of dual fuel engines running on natural gas/LPG by using pilot fuel derived from jojoba seeds

Experimental study on diesel engine nitrogen oxide reduction running with jojoba methyl ester by exhaust gas recirculation

Improving the performance and emission characteristics of a diesel engine fueled by jojoba methyl ester-diesel-ethanol ternary blends