Roslindawati Haron

Pretreatment of empty palm fruit bunch for production of chemicals via catalytic pyrolysis

The effect of chemical pretreatments using NaOH, H(2)O(2), and Ca(OH)(2) on Empty Palm Fruit Bunches (EPFB) to degrade EPFB lignin before pyrolysis was investigated. Spectrophotometer analysis proved consecutive addition of NaOH and H(2)O(2) decomposed almost 100% of EPFB lignin compared to 44% for the Ca(OH)(2), H(2)O(2) system while NaOH and Ca(OH)(2) used exclusively could not alter lignin much. Next, the pretreated EPFB was catalytically pyrolyzed. Experimental results indicated the phenolic yields over Al-MCM-41 and HZSM-5 catalysts were 90 wt% and 80 wt%, respectively compared to 67 wt% yield for the untreated sample under the same set of conditions. Meanwhile, the experiments with HY zeolite yielded 70 wt% phenols.

Overview of Biodiesel Wastes Utilization for Hydrogen Production

Nowadays, biodiesel costs more than fuels produced from crude oil due to prices of raw materials. The production cost of biodiesel could be reduced if cheaper raw material is used and utilization of the biodiesel by-product is one of the promising options for lowering the production cost. Hydrogen will play an important role in the worlds future. Therefore, hydrogen production from renewable sources such as glycerol, is gaining attention. This article reviews on the latest development on hydrogen production from biodiesel waste. Glycerol reforming and biotransformation are two main routes available for converting crude glycerol to hydrogen. In more recent years, there have been extensive studies, and some encouraging results on processes for utilization of crude glycerol for hydrogen production. However, many of the proposed technologies still need further development to make them cost-effective and operationally feasible processes to directly utilize crude glycerol from biodiesel production on a large scale.

Dark fermentation of crude glycerol by locally isolated microorganisms to hydrogen

The need for sustainable management of the waste along with the availability of crude glycerol (CG) has generated interest on glycerol-based cultures. To date, CG is used as cheap substrate in fermentation in replace of glucose or other types of substrates. In this study, raw CG is used as a sole substrate for the locally isolated microorganisms from biodiesel sludge to produce bio-hydrogen via dark-fermentation. Prior to the isolation of potential microbes, preliminary test was done to ensure that hydrogen is among the gases produced during the fermentation. This preliminary test was conducted using the wastewater. Mixed-microbes including the potential microbes were expected to be in the wastewater and help in the bioconversion of both pure and crude glycerol to hydrogen. The experiment using pure commercial glycerol was also conducted to compare the performance and conversion of the hydrogen. The gas was collected in a sampling bag. Analysis of the gas was done using GC-TCD with argon as carrier gas. Isolation and screening of potential hydrogen producer has successfully isolated 10 potential microorganisms. Screening was based on their ability to produce gas globules in the agar. Findings on the gas analysis showed that the microorganisms produced only hydrogen and carbon dioxide. No traces of methane was observed from the GC analysis indicating that no methanogenic microbes in the mixedcultures, and no foam was produced during the dark-fermentation using crude glycerol as carbon source. In contrast, foam is formed in the fermentation of pure commercial glycerol. From the findings, it can be concluded that the isolated microbes has the potential to produce hydrogen from the raw crude glycerol.