The continuous increasing demand for energy and the diminishing tendency of petroleum resources has led to the search for alternative renewable and sustainable fuel. Biodiesel is best substitute for petro-diesel and also most advantageous over petro-diesel for its environmental friendliness. The quality of biodiesel fuel was found to be significant for its successful use on compression ignition engines and subsequent replacement of non-renewable fossil fuels. Conventional biodiesel separation and purification technologies were noticed to yield lower quality biodiesel fuel with resultant excessive energy and water consumptions. Membrane technology showed more potential for effective and efficient separation and purification of biodiesel. This technology need be explored for the attainment of better quality biodiesel fuels. This paper reviews the technologies used for the biodiesel separation and purification, biodiesel quality, and its effects on diesel engines. Biodiesel biodegradability, lubricity, stability, economic importance, and gaseous emissions have been discussed.

http://maghaleh2012.persiangig.com/document/amin/up2.pdf

High quality biodiesel and its diesel engine application: A review

Within the present contribution we highlight the feasibility of standard refinery units for the production of biofuels from different biomass-derived feedstock. The energy densification of biomass, as well as it’s logistics and incorporation within the refinery supply chain is thoroughly discussed. Likewise, special attention is focused on the catalytic cracking and hydrotreating of triglyceride-rich biomass feedstock, which is probably the most suitable one for co-processing in conventional refinery conversion units. However, the opportunities of other highly oxygenated feedstocks such as pyrolysis oils and sugars are also discussed. Conversion of different feedstocks into conventional liquid fuels by coupling of aqueous phase reforming (APR) with catalytic systems typical of standard petroleum refineries is also evaluated. Thus, here we review the chemistry, catalysis and challenges involved in the production of biofuels from biomass in conventional refineries.

Biomass as renewable feedstock in standard refinery units. Feasibility, opportunities and challenges

The predicted shortage of fossil fuels and related environmental concerns have recently attracted significant attention to scientific and technological issues concerning the conversion of biomass into fuels. First-generation biodiesel, obtained from vegetable oils and animal fats by transesterification, relies on commercial technology and rich scientific background, though continuous progress in this field offers opportunities for improvement. This review focuses on new catalytic systems for the transesterification of oils to the corresponding ethyl/methyl esters of fatty acids. It also addresses some innovative/emerging technologies for the production of biodiesel, such as the catalytic hydrocracking of vegetable oils to hydrocarbons. The special role of the catalyst as a key to efficient technology is outlined, together with the other important factors that affect the yield and quality of the product, including feedstock-related properties and various system conditions.

Catalytic applications in the production of biodiesel from vegetable oils.

The current status and perspectives of biofuel production via catalytic cracking of edible and non-edible oils

Biofuels have become an attractive alternative fuel because of their possible environmental benefits and the current concern over the depletion of fossil fuel sources. The demand for biofuels will rise in the future due to the rise in the price of fossil fuel, energy security reasons, environmental and economical issues. Vegetable oils are the most common feedstocks and are converted into liquid fuels due to their high energy density, liquid nature and availability as a renewable feedstock. Several types of vegetable oils with a diversified composition in fatty acids can be used. Beside edible vegetable oils, non-edible and used cooking oils have also received considerable attention because they do not compete with food sources and are less costly to procure. Beside vegetable oils, bio-oil obtained from the pyrolysis of biomass has also been upgraded through catalytic cracking process to obtain biofuel. Catalytic cracking is one of the most efficient methods to produce biofuel, especially biogasoline, by cracking of vegetable oil in the presence of suitable catalyst. The catalytic cracking of edible and non-edible oils requires the development of proper cracking catalysts and reactors for the production of biogasoline. The present article summarizes progress in the development of the technology in biofuel production viacatalytic cracking. The paper also covers the different types of feedstock suitable for the production of biofuel, potential cracking catalysts, catalytic cracking mechanisms, different types of catalytic reactors, and biofuel characteristics. Important issues like catalyst choice and reactor design must be addressed before catalytic cracking can be commercially implemented. The paper also presents the future prospects of this technology in biorefineries for the production of biofuels.

Honghong Shan

Papers

Alternative Processing Technology for Converting Vegetable Oils and Animal Fats to Clean Fuels and Light Olefins