A.H. Sebayang

Second generation bioethanol potential from selected Malaysia's biodiversity biomasses: A review

Rising global temperature, worsening air quality and drastic declining of fossil fuel reserve are the inevitable phenomena from the disorganized energy management. Bioethanol is believed to clear out the effects as being an energy-derivable product sourced from renewable organic sources. Second generation bioethanol interests many researches from its unique source of inedible biomass, and this paper presents the potential of several selected biomasses from Malaysia case. As one of countries with rich biodiversity, Malaysia holds enormous potential in second generation bioethanol production from its various agricultural and forestry biomasses, which are the source of lignocellulosic and starch compounds. This paper reviews potentials of biomasses and potential ethanol yield from oil palm, paddy (rice), pineapple, banana and durian, as the common agricultural waste in the country but uncommon to be served as bioethanol feedstock, by calculating the theoretical conversion of cellulose, hemicellulose and starch components of the biomasses into bioethanol. Moreover, the potential of the biomasses as feedstock are discussed based on several reported works.

A perspective on bioethanol production from biomass as alternative fuel for spark ignition engine

The increasing consumption of fossil fuels has led to the development of alternative fuels for the future. Domestic biofuel production and the utilization of alternative fuels can decrease dependency on petroleum oil, reduce trade deficits, reduce air pollution and reduce carbon dioxide emission. Bioethanol is a renewable fuel produced by the fermentation of sugar which is derived from plants such as sugarcane or beet, maize, or cassava etc. However, bioethanol consumption in an engine is approximately 51% higher than gasoline since the energy per unit volume of ethanol is 34% lower than for gasoline. Bioethanol is an oxygenated fuel that contains 35% oxygen, which can reduce particulate matter and NOx emissions caused by combustion of the fuel. Therefore, bioethanol–gasoline blends can significantly reduce petroleum use and GHG emission. In addition, utilization of lignocellulosic materials in bioethanol production is the most viable pathway from an environmental point of view. This paper reviews the current status and technologies involved in bioethanol production and the properties and engine performance from various biomass feedstocks which are the recommended sustainable alternative fuel in the future.

Physicochemical property enhancement of biodiesel synthesis from hybrid feedstocks of waste cooking vegetable oil and Beauty leaf oil through optimized alkaline-catalysed transesterification

Recycling waste cooking vegetable oils by reclaiming and using these oils as biodiesel feedstocks is one of the promising solutions to address global energy demands. However, producing these biodiesels poses a significant challenge because of their poor physicochemical properties due the high free fatty acid content and impurities present in the feedstock, which will reduce the biodiesel yields. Hence, this study implemented the following strategy in order to address this issue: (1) 70 vol% of waste cooking vegetable oil blended with 30 vol% of Calophyllum inophyllum oil named as WC70CI30 used to alter its properties, (2) a three-stage process (degumming, esterification, and transesterification) was conducted which reduces the free fatty acid content and presence of impurities, and (3) the transesterification process parameters (methanol/oil ratio, reaction temperature, reaction time, and catalyst concentration) were optimized using response surface methodology in order to increase the biodiesel conversion yield. The results show that the WC70CI30 biodiesel has favourable physicochemical properties, good cold flow properties, and high oxidation stability (22.4 h), which fulfil the fuel specifications stated in the ASTM D6751 and EN 14214 standards. It found that the WC70CI30 biodiesel has great potential as a diesel substitute without the need for antioxidants and pour point depressants.