Category Archives: Advances in Biofuels

Investment Opportunities in Biofuels

In view of the increasing environmental concerns particularly relating to the use of fossil fuels, new solutions to minimize the greenhouse gas effect are continuously sought for. Among the options, biomass has been recognized as the most important energy source for biofuel production to mitigate greenhouse gas emissions (Khan et al. 2009). Furthermore, increasing energy security fears, rising petroleum prices, low barriers to market entry, and government support in increasing number of coun­tries are expected to drive up the world demand for biofuels to a greater height in the near future. A number of technologies are available for the conversion of plant bio­mass of either sugar, starch and oil crops, or cellulosic feedstock to bioethanol, biodiesel, or other types of biofuels (Demirbas 2010).

Today, bioethanol and biodiesel are the two most significant biofuels in the mar­ket. They are largely derived from the use of starch, sugar, and vegetable oils as feedstock. Because of the use of these essentially food-based products as feedstock for biofuels, they will compete with food use. Hence, there is the tendency of policy shift away from traditional use of food-based biomass feedstock to cellulosic

Table 2.2 Estimated production of oil palm biomass materials in Sabah in 2010-2020

Biomass materials

Production (dry weight, million tonnes/year)

Oil palm frond

13.8-17.3

Oil palm trunk

4.2-5.3

Mesocarp fiber

2.1-2.6

Empty fruit bunch

2.0-2.5

Palm kernel shell

1.2-1.5

Palm oil mill effluent

0.6-0.8

Total

24-30

Source: After Agensi Inovasi Malaysia (2011)

biomass feedstock for biofuel production (Schnepf 2011). However, the technology for cellulosic biofuel production may take more time before it hits commercial pro­duction scale. This development is expected to create investment opportunity in the use of oil palm biomass for biofuel production.

The oil palm industry in Sabah is estimated to produce a total of about 24 million tonnes of dry palm-based biomass in 2010 with the respective component biomass materials as presented in Table 2.2. The volume of palm-based biomass is expected to increase to around 30 million tonnes by 2020. If these palm-based biomass mate­rials are put to good use, it has the potential of generating million or even billion gallons of biofuel annually.

Concrete Materials

In the palm oil mill, the boiler ash (from PPF, PKS and EFB) creates a lot of envi­ronmental problems as their disposal methods are unsafe. The ash is normally dumped at landfills without any sustainable means of utilising it. Recent studies have reported many different ways of transforming the palm ash to value-added products such as concrete materials which are used in buildings. Moreover, the quantity of OPW which is not utilised by the boiler as fuel can also be combusted into ash and used for as concrete material. One important benefit of using OPW as concrete materials is that they are organic and therefore do not contaminate or leach out to produce toxic substances once they are bound in concrete matrix.

Ground palm ash would make an excellent pozzolanic material which can be used as a cement replacement in concrete (Chandara et al. 2010; Yin et al. 2008). The replacement of Portland cement type I by 30% palm fuel ash (from EFB, PPF and PKS) gave the compressive strengths of concrete at 90 days higher than that of concrete made from Portland cement type I alone (Tangchirapat et al. 2007). Ismail et al. (2011) have investigated into the residual compressive strength of concrete containing OPW ash after exposure to elevated temperatures and subsequent cool­ing. The residual performance was found to be higher in OPW concrete than in the normal concrete. Concrete containing OPW as aggregate materials therefore serves as potential building concrete for constructing pavements, floorings and walls.

PKS is used as coarse aggregate in road binder course in order to add more strength to the asphalt concrete (Yusoff 2006; Teo et al. 2007). Concrete with PKS as coarse aggregates has been proven to exhibit good properties in terms of com­pressive strengths, workability and density (Basri et al. 1999; Shafigh et al. 2012). Recently, a new method has been investigated into by Shafigh et al. (2011) who showed that it is possible to produce grade 30 PKS concrete without the addition of any cementitious materials. Tay and Show (1995) have concluded that the work­ability, setting times and soundness test results of concrete containing ash from EFB are satisfactory with no segregation. Their results also indicated the high possibility of blending the ash with small amounts of ordinary Portland cement for concrete making without detrimental effects on long-term strength property. Blended cement paste with high fineness OPW ash possesses a higher compressive strength than that with coarse OPW ash (Kroehong et al. 2011).

Biodiesel Production Costs

The world biodiesel production was rapidly expanded with shocking increment of 5,000% from years 2001 to 2006 (Szulczyk and McCarl 2010). These figures are likely to increase further, due to active support from many countries (the European Union, the United States, Brazil, China, India, and some Southeast Asian countries such as Malaysia and Indonesia) which accelerate the biofuel production. Efforts have been done to further catalyze the growth of biodiesel market in these countries: (1) implementation of 2% (B2), 5% (B5), or 20% (B20) blend of biodiesel in con­ventional diesel fuel, without any engine modification, and (2) substantial support from government such as consumption incentives (fuel tax reduction) and produc­tion incentives (tax incentives and loan guarantees) (The World Bank 2008).

However, there are also negative forces that hinder the expansion of the biodiesel industry:

1. Food-grade biodiesel is still far more expensive than conventional petroleum — derived diesel (biodiesel costs 1.5 to 3 times more than fossil diesel in developed countries).

2. Demand for biodiesel will fade if government subsidies are suspended.

3. Issues on using fertile lands for energy crops and biofuels production reduces the land space available for food crops, contributing to an increase in prices of staple foods and making them more scarce.

4. Water pollution and wastage of large amount of water for biodiesel post-treatment. The main capital cost for biodiesel production including (Kiss et al. 2010):

1. 7% equipment and investment (depreciation charge and maintenance).

2. 75% of feedstock (vegetable oil).

3. 2% of utilities (electrical energy and steam consumption).

4. 12% catalyst and chemicals (methanol, catalyst, and chemical for washing process).

5. 3% labor cost.

6. The rest 1% of costs as site (transport, distribution, and selling costs) or country specific (taxes, governmental subsidies, and credits) and management costs (administration, general expenses) was assumed to be subsidies by government and does not influence the overall production costs.

Note that in all the cases cited above, oil feedstock cost comprises a very sub­stantial portion of overall operating cost and it is the main obstacle in commercial­ization of biodiesel. The competitiveness of biodiesel relies on the price of the biomass feedstock and costs associated with the conversion technology. This high­lights the need for the development of new technologies allowing the use of lower value feedstock for transesterification process.

To select a potential feedstock with reasonable value, it must be (Moser 2009):

1. Highly available at the lowest price possible with desired characteristic includ­ing high oil content

2. Favorable fatty acid composition (saturated or unsaturated)

3. Low agriculture inputs (water, fertilizers, soils, and pesticides)

4. Controllable growth and harvesting season

5. Consistent seeds maturity rates and potential market for agricultural by-products

In general, biodiesel feedstock can be divided into four main categories which are (1) edible vegetable oil, (2) nonedible vegetable oil, (3) waste or recycled oil, and (4) animal fats (Lim and Lee 2010). The most common feedstock employed in biodiesel production is edible and inedible oil from oleaginous plants grown in dif­ferent regions. Table 10.1 showed the profile of common feedstock that used for biodiesel production.

Other than selecting a suitable raw material for economically feasible produc­tion, catalyst and chemical is another important criterion that should take into account for transformation of traditional technology. The potential catalyst for industrial biodiesel production process should include these characteristics: (1) high FFAs and water content tolerance, (2) catalyst poisoning and leaching resistant,

Table 10.1 Profile of common biodiesel feedstock

Type

Triglyceride

Oil yields (wt%)

Oil yields (kg/ha)

Price of crude (USD/tonnes)

Edible

Soybean oil

20

520

735

Rapeseed oil

33-48

1,000

815-829

Sunflower oil

28-50

952

1,113-1,195

Palm oil

50

5,000

610

Nonedible

Jatropha oil

27-30

1,590

125

Microalgae oil

50

12,000-460,000

N/A

Waste and recycle

Waste cooking oil

360

(3) ability to catalyze transesterification and esterification, (4) stable, high activity in water and leach proof, (5) low activation, (6) high selectivity and conversion rate, (7) enhancing the number and type of active sites (both Lewis acid-base sites and Bronsted acid-base sites have the ability to catalyze the oil transesterification reac­tion; catalyst activity is closely related to the acid/base strength), (8) good textural properties of the catalyst also impact the catalyst’s activity, such as specific surface area, pore size, pore volume, to minimize mass transfer limitations, and (9) high reusability (Di Serio et al. 2007). A catalyst with all these criteria shall create a new process for high-grade biodiesel with competitive price to petrodiesel. Even though high feedstock oil prices have lately tended to reduce biodiesel production, development of heterogenized technology for low-grade feedstock may contribute to long-term expansion in the biodiesel industry.

Storage Stability and Reusability

The operational stability was assessed for both free and immobilized lipase in phos­phate buffer of pH 7. The immobilized lipase was also stored in 50 mM Tris-HCl buffer (pH 8.0) containing 0.3 M CaCl2 (T/Ca solution). All these solutions were stored at 4°C, and relative activities were determined for a period of two weeks and are shown in Fig. 12.5d. Also, the immobilized lipase was repeatedly used for hydrolysis ofp-NPP in order to evaluate its reusability property. From Fig. 12.5e, it can be seen that the immobilized lipase retained 75.54% of its initial activity upon tenth hydrolysis of p-NPP. Loss of activity can be attributed to enzyme leakage and also deactivation of lipase during the reuse procedures.

Advances in Biofuels

The book “Advances in Biofuels” presents the contributions of some researchers in modem fields of biofuels, serving as valuable information for scientists, research­ers, graduate students, and professionals. The focus is on several aspects of biofuels technology, examining complex technical issues and some aspects of the diverse resources and their application for industrial and policy matters. The book covered some topics as follows:

The book is made up of 14 chapters, grouped together in five parts, on different tech­nical fields. In Chap. 1, the first-generation, second-generation, and third-generation biofuels are discussed. The focus has been made on the research and development of biofuels in Malaysia with much attention paid on palm oil. The government’s support on renewable energy and various policies for the biofuel research along with the issues and challenges for the production and utilization of oil palm biomass are also highlighted.

Chapter 2: The recent progress of oil palm plantation industry in the state of Sabah, the biggest oil palm growing state in Malaysia, and establishment of Palm Oil Cluster (POIC) in Lahad Datu for speeding up the value-adding oil palm down­stream industries as the growth engine to accelerate the economic development in the state are highlighted.

Chapter 3: Potential technologies for the conversion of biomass to biofuels are highlighted. Biomass utilization reduces the dependency on fossil-based fuel and will help to prolong the fuel supply and at the same time reduce the environmental issues related to CO2 emission. The effect of steam and newly developed bimetallic catalyst (Fe/Ni/Zeolite-P) on palm oil wastes including palm shell (PS) and palm oil fronds (POF) decomposition for H2 production that was experimentally investigated in thermogravimetric analysis-gas chromatography (TGA-GC) is discussed.

Chapter 4: Different biomass resources used for energy by conversion process are explained. Thermochemical processes for hydrogen production are detailed in this chapter. Biomass gasification using supercritical water to produce hydrogen gas is stated as a new approach. But the harmful heteroatomic compounds produced with this need to be taken into account. A newly developed on-line mass spectrometry for the determination of the sulfur compounds released during hydrothermal reaction from L-cysteine as model compound and durian fruit as practical sample was conducted. The effect of alkaline Ca (OH)2 addition on the formation of sulfur heteroatom compounds has also been studied in detail.

Chapter 5: Oil palm wastes (OPW) comprising both solid and liquid residues from the oil palm industry are among the most abundant agricultural wastes in the world. The inefficient method of disposal and management of OPW has necessi­tated the need to recover value-added products from them. This study reviews the vital characteristics of OPW suitable for the synthesis of value-added bio-products. Simultaneous production of oil palm fresh fruit bunches (FFB) and the utilization of the plantation wastes for food and animal feed with integration of animal husbandry in the oil palm plantation are discussed.

Chapter 6: Triglycerides are the main constituents of vegetable oils. The tempera­ture distributions of sunflower and soybean oil combustion flames using the semawar burner have been investigated in this research using spectroscopic method. The spon­taneous NO emission has also been visualized by ICCD camera. It has obviously seen that NO emission of sunflower oil is more significant than soybean oil due to the higher temperature of sunflower oil combustion flames. The presence of CO2, CO, H2O, and NO from sunflower and soybean oil combustion flames has been observed using FT-IR, and CO2 has been also visualized using infrared camera.

Chapter 7: Normally bioethanol is obtained from different vegetable oils. Here a low-cost alternative technology for production of bioethanol from EFB of palm oil in Malaysia is discussed. Malaysia can be a pioneer in lignocellulose’s ethanol tech­nology using EFB as a resource by integrating a bioethanol plant near palm oil mills. This new industry can generate various spin-offs beneficial to the country. Independent palm oil processing mills would be expected to be the main contribu­tors of EFB as they do not have plantation to decompose the EFB residues generated from their mills. The development of a bioethanol demonstration plant has to over­come barriers related to the supply chain. This can be done through educational campaigns on the benefits of a renewable energy industry.

Chapter 8: Biodiesel has become more attractive as an alternative fuel resource because of its environmental benefit such as biodegradable, nontoxic, and low emis­sion profiles. The following areas are covered by this chapter: current production of biodiesel; bio-green technology; enzymatic transesterification; lipid sources for biodiesel production; and study on mass production of biodiesel. It has been con­cluded that production of biodiesel using bioroute, especially enzymatic reaction, showed a big potential in expanding to a bigger scale productions to support the diminishing of energy resources. The only challenge using enzyme technology is that the life span for lipase was short, and this will give motivation for researcher to find ways to curb the problem. Using immobilized lipase was one of the solutions for the issue raised and can be improved further. Packed-bed immobilized enzyme reactors could be the reactor configuration that can be used to deliver mass produc­tion of biodiesel.

Chapter 9: Various types of catalysts for biodiesel production, especially homogeneous and heterogeneous catalysts, are briefed here. Novel processes for biodiesel production are highlighted with emphasis on ultrasound-assisted process, microwave-assisted process, and reactive distillation. Thus, here, different types of catalysts are produced and studied in order to maximize biodiesel yield and at the same time minimize catalyst use without sacrificing their catalytic performance. The authors also emphasize on the choice of nonedible oils for biodiesel production such as waste cooking oil. Further studies need to be conducted to identify new novel processes that have the capability to produce biodiesel effectively at moderate operating conditions without sacrificing the yield and conversion.

Chapter 10: Selection of an effective catalyst together with suitable feedstock is necessary to create an economically viable and sustainable energy source. From the commercial point of view, solid base catalysts are more effective than acid catalysts and enzymes. The transesterification activity of heterogeneous base-catalyzed reac­tion is more reactive than the solid acid catalyst in terms of lower reaction tempera­ture, shorter reaction time, and smaller catalyst amount. This chapter reviews various types of homogeneous and heterogeneous catalysts used for transesterification of high free fatty acid oil (Jatropha oil). The process involves single-step or two-step reactions which rely on the physicochemical properties and flexibility of catalyst.

Chapter 11: The advantages of enzymatic transesterification over conventional methods of biodiesel production are discussed here. An enzymatic biodiesel process can also pave the way for versatile products to be coproduced from the same feed­stock source. This is possible only through the choice of right enzymatic process to make it more economically feasible. This chapter introduces a patented process that can meet these criteria, the ET Process®. Through enzymatic method, biodiesel can be produced in an environmental friendly manner. To make the process into com­mercial scale, the oil cost feedstock should be lowered. New processing configurations are illustrated using crude palm oil and coconut oil as examples.

Chapter 12: The importance of Jatropha curcas as a nonedible biodiesel feed­stock is highlighted in this chapter. Different methods of oil extraction from Jatropha seeds and various ways of biodiesel production from this oil are also briefed. Immobilization of lipases for enzymatic transesterification and various ways used for immobilizing lipase are also discussed. Immobilization of lipase in a hybrid matrix and its application in biodiesel production are highlighted.

Chapter 13: Currently, bioethanol is produced from land-based crops, but in the future marine biomass could be used as an alternative biomass source because it does not take up land area for cultivation. In this chapter, seaweed, Eucheuma cot — tonii (cultivated in Sabah, Malaysia), was tested for its potential for bioethanol pro­duction via fermentation by yeast, Saccharomyces cerevisiae. The potential of macroalgae as fermentation feedstock depends on its carbohydrate and cellulose. The higher productivity obtained in this study shows that macroalgae is a promising feedstock for bioethanol production.

Chapter 14: Importance of microalgae has been increasing in many fields of research, including biofuels and pharmaceutics, because of their high photosyn­thetic rate. The membrane integrated with a photobioreactor for CO2 mitigation by microalgae can be considered as a relatively new field. The integration of a mem­brane contactor with a photobioreactor serves two major purposes for the mitigation of CO2 by microalgae, i. e., to enhance the mass transfer and interfacial contact between two different phases and to increase the exchange process of CO2-O2 by microalgae in the photobioreactor.

The editors wish to thank all the researchers who accepted the invitation to con­tribute, on the basis of their scientific potential, within the topic to date. Some valu­able new researches in this area are shared within this book.

Kota Kinabalu, Sabah, Malaysia Ravindra Pogaku

Rosalam Hj. Sarbatly

Introduction

The biofuel industry all over the world is poised to make important contributions to meet every country’s energy needs by supplying clean, environment-friendly fuel. The ethanol industry, though mature, can benefit from improved agricultural prac­tices in palm and sugarcane cultivation, more efficient production processes, and the use of alternate feedstock including cellulosic material. On the other hand, biodiesel industry is at the incubation stage, and large cultivation of Jatropha and other spe­cies and infrastructure for oilseed collection and oil extraction are being established so that the industry can be placed on a rapid growth track.

Editor

Ravindra Pogaku is an internationally renowned expert in bio-energy and biofuel field. He has rich versatile and varied experience in teaching, research, industry, and administrative fields spanning over 30 years.

Presently, he is serving as a professor of Chemical and Bioprocess Engineering at Universiti Malaysia Sabah (UMS), Kota Kinabalu, Sabah, Malaysia. He is the board of studies and committee member for many institutions.

Prof. Ravindra’s research interests include biofuels, wealth from waste, and bio­process engineering. At present his research group focus is on bio-derived energy for sustainable development. His research work has culminated in over 170 research publications. He has published and edited books. He is the editor-in-chief, editorial board member, guest editor for many referred journals, and reviewer of many peer journals. He is the international advisory member for many conferences.

He has carried out as many as 25 national, international, and industrial research projects. He was bestowed with the national and international prestigious and distin­guished awards. He is a resource consultant to UNESCO, in the field of energy, and also extends consultancy services to chemical and bioprocess industry. His focus is on the issues of green engineering and technology for sustainable development of the society.

Co-editor

Dr. Rosalam Sarbatly is an associate professor of Chemical and Environmental Engineering and the dean of Engineering and Information Technology, Universiti Malaysia Sabah, head of membrane research group and a member of Institute of Engineer Malaysia (IEM) and associate member of Institute of Chemical Engineer (UK). His current research interest is membrane and nanofibre technology and bio­energy from microalgae. His expertise has been recognized worldwide through the appointment as an editorial board of journals and peer reviewer. He is the key researcher for national and international collaboration such as Tokyo Eco Net Co. Ltd., Japan, for commercialization of nanofibre technology for water desalination and oil spillage cleaning system and products to improve the energy efficiency of the palm oil boiler.

Experimental

L-Cysteine purchased from Sigma-Aldrich was used as a model sample of biomass. Standard Ca(OH)2 was obtained from Sigma-Aldrich. Durian pulp was purchased from local market in form of frozen durian.

Figure 4.1 shows the schematic diagram of a combination system of hydrother­mal reaction and mass spectrometry developed by our group for direct detection of heteroatomic compounds generated during hydrothermal reactions.

The system has been reported in our previous paper (Alif et al. 2011). A stainless steel tube from the Swagelok (V= 10 cm3, ID = 1.3 cm, L = 14.4 cm) was used as a
reactor cell (a) for hydrothermal reaction. Approximately 0.2 g of L-cysteine or 0.5 g for durian was placed into the reactor with 6 ml of deionized H2O. Air in the reactor was purged with nitrogen gas to give an inert atmosphere. The reactor was put into the GC oven (Shimadzu GC-8A) (b) programmed at different temperatures (250, 300, 350, and 380°C). The reactor was kept at each temperature until a con­stant pressure was reached. The pressure inside the reactor was monitored simulta­neously by the pressure sensor (c). After the reaction is completed at a certain time, the gas produced at the desired temperature and pressure was stored in the tube between the two valves (d and e) (V= 1.6 ml, ID = 0.2 cm, L = 10 cm). By opening the second valve (e), the products were introduced from a capillary column (f) into a quadrupole mass spectrometer (Anelva AQA-360) through the sampling (g) and skimmer (h) cones. A scan mode or selective ion monitoring (SIM) mode was used. A gaseous sample uptake was conducted for 2 min at all temperatures.

Prospect of Biodiesel as Renewable Energy Sources

Alternative fuels for diesel engines are becoming increasingly important due to diminishing petroleum reserves. The U. S. Energy Information Administration declared that total world energy consumption in 2005 was 488 EJ (exajoule, 1018J) or 463 Quad (quadrillion Btu, 1015 Btu). World consumption is expected to surpass 60% increase in energy consumption or equivalent to 650 EJ by 2025, and this value reflects the degree of industrialization, efficiency of primary energy source used, and energy conservation (Energy Information Agency 2007). Currently, available fossil fuel sources are estimated to become depleted in the next century, with petro­leum reserves depleted within 40 years (BP 2005; Energy Information Agency 2007). As a consequence, crude oil prices have risen from less than $20/barrel in the 1990s to nearly $100/barrel in 2007 (Kinney and Clemente 2005).

The idea of using plant oils as fuel was first substantiated by E. Duffy and J. Patrick in 1853 and tested on engines by 1893 by R. Diesel (Feofilova et al. 2010) using peanut oil. R. Diesel stated in his speech at the Great Britain Technological Institute in 1912 “the use of plant oils as fuel for cars was insignificant now but by time it may become as important as coals and oil products now” (Feofilova et al. 2010). Amazingly nowadays, biodiesel is gaining more importance as an alternative fuel, and the production of biodiesel increased significantly. From 1998 to 2008, the European countries increased the production of biodiesel 33 times higher (475 thou­sand tons up to 16 million tons) followed by United States with two million gallons in year 2000 to 700 million gallons in 2008. Recently, in developing countries (China, Brazil, and Indonesia), development of biodiesel fuel became important and increased tremendously including Malaysia (Feofilova et al. 2010).

Biodiesel can be used in diesel engine without major modification to the engine due to similar properties to fossil fuel (Puhan et al. 2005; No 2011). Biodiesel refers to a nonpetroleum-based diesel fuel consisting of short-chain alkyl (methyl or ethyl) esters that can be made by transesterification of vegetable oil or animal fats. Biodiesel has attracted more and more attention in recent years because it is biode­gradable, renewable, and environmentally friendly. Biodiesel fuel produced on a sustainable basis offers the benefits of energy independency and security, economic and social cohesion (Howell and Jobe 2005), and being environmentally friendly ( Zhang et al. 2003). These factors have created the driving force and motivation for this alternative fuel-biodiesel production.

The utilization of biodiesel possesses several distinct technical advantages and disadvantages compared to petro-diesel (Table 8.1). By considering the positive and negative effects, biodiesel is still considered as a clean fuel that can combat global warming and stabilize the climate through the reduction of CO2 emissions (Drapcho et al. 2008; Arent et al. 2011; Meunier 2007; Ellington et al. 1993) in long term, and researchers are continuously finding alternatives and develop technologies to mini­mize the cost of production. Furthermore, the utilization of biodiesel would largely enhance the commercial value for fats and oils, the need to build biodiesel plants, and the employment of human capital to operate these plants. Thus, using biodiesel

Table 8.1 List of advantages and disadvantages ofbiodiesel as engine combustion fuel compared to petro-diesel (Meher et al. 2006; Demirbas 2009)

Подпись:

image054

Disadvantages

would gain economic benefits for farmers, local communities, and the nation as a whole. Increased utilization of biodiesel results in significant economic benefits for both the urban and rural sectors, as well as the balance of trade (Howell and Jobe 2005).

Enzymatic Process for Biodiesel and High Value-Added Products

George Chou

Abstract An enzymatic biodiesel process can not only overcome the challenges faced by conventional chemical processes but also pave the way for versatile products to be coproduced from the same feedstock source. However, this is only possible and cost-effective through the right enzymatic process. This paper intro­duces a patented process that can meet these criteria, the ET Process®. Unlike before, biodiesel can now be produced in a very environmentally friendly manner. However, in order to maintain competitive commodity pricing without subsidies, oil feedstock cost should be lowered, i. e., allowing the direct use of oil with high free fatty acid content, and the process should be integrated so that different high value — added co-products can be produced. To be sustainable and profitable, optimal utili­zation of feedstock source should be taken into account. New processing configurations are illustrated using crude palm oil and coconut oil as examples.

Keywords Biodiesel • Free fatty acids • Feedstock • Enzymes

11.1 Introduction

Although the biodiesel industry has developed into a major pillar for liquid biofuel commodity, it still relies on commercial chemical approaches, such as those using acid and base catalyses, which are not entirely efficient or cost-effective. These types of technologies are known to face many process and environmental problems. For example, the free fatty acid (FFA) content allowable in the feedstock cannot exceed 1 wt% and the moisture level is likewise restricted to low levels. If the FFA level is high, such as the case with low-quality feedstock, then it needs to be removed or the system is preceded by an acid process to reduce FFA level enough for it to be

G. Chou (H)

Sunho Biodiesel Corporation, Taipei, Taiwan e-mail: gc@sunhobiodiesel. com

R. Pogaku and R. Hj. Sarbatly (eds.), Advances in Biofuels, 179

DOI 10.1007/978-1-4614-6249-1_11, © Springer Science+Business Media New York 2013

processed by base catalysis. Refining or addition of an acid process both contribute to increased final product cost. Because it is a slow process, a separate acid catalysis system is not economically feasible to set up given the high capital investment needed to convert, say, only 10-25% FFA in the feedstock. Other related problems are the significant amount of wastewater produced, chemical disposal and low qual­ity of glycerol co-product. The result is an unavoidably high product cost, with which it cannot survive unless subsidies are present. A more long-term solution is therefore necessary.

From a business point of view, the biodiesel industry has two options to increase survival: one is to cut costs and the other is to increase profits through co-production. It is not as easy to achieve either of these using the conventional chemical approach. This is due to the very nature of the chemical approach itself. In contrast, an enzy­matic approach has specific and clean reactions that could address the issues mentioned.

Biodiesel is primarily a commodity product and must therefore maintain low or competitive pricing. Normally, the biodiesel market competes with diesel derived from crude oil. To lower costs, it is necessary to use a low-cost feedstock, which generally pertains to feedstock with high FFA content. Alternatively, depending on the feedstock used, price can be balanced off by profit from co-products. To increase profit from a biodiesel plant, the system design can be integrated to develop multi­ple products, including high value-added ones, technical or pharmaceutical grade glycerol, phytochemicals and nutrients. It allows the biodiesel plant to produce maximum profit at the lowest cost possible.

Fermentation Study on Macroalgae Eucheuma cottonii for Bioethanol Production via Varying Acid Hydrolysis

Rachel Fran Mansa, Wei-Fang Chen, Siau-Jen Yeo, Yan-Yan Farm, Hafeza Abu Bakar, and Coswald Stephen Sipaut

Abstract The depletion of fossil fuel and the increase of human population lead to the search for more sustainable alternatives. Currently, bioethanol is produced from land-based crops, but in the future, marine biomass could be used as an alternative biomass source because it does not take up land area for cultivation. In this chapter, seaweed Eucheuma cottonii (cultivated in Sabah, Malaysia) was tested for its poten­tial for bioethanol production via fermentation by yeast Saccharomyces cerevisiae. E. cottonii contains cellulose and carrageenan which will be hydrolysed into glu­cose and galactose, which in turn was converted to ethanol by the yeast. This study showed that the extracted seaweed gives higher percentage of ethanol (9.6% v/v) compared to non-extracted seaweed. Subsequently, it was found that low molarity and high-temperature acid hydrolysis at 0.0 M, 100% (8.4% v/v) produced the most ethanol. It was followed by hydrolysis 0.1 M, 30% (7.7% v/v); 0.4 M, 30% (4.7% v/v); and 0.4 M, 100% (3.4% v/v) with fresh feedstock. In this research, among the three fermentation media, it was found that Yeast Peptone Dextrose (YPD) broth yields the highest percentage of ethanol (9.6% v/v) followed by Yeast Extract Peptone (YP) broth producing 4.7% v/v ethanol. This productivity level makes macroalgae a promising substrate for bioethanol production.

Keywords Eucheuma cottonii • Bioethanol • Fermentation • Acid hydrolysis • Extraction • Fermentation media

R. F. Mansa (*) • W.-F. Chen • S.-J. Yeo • Y.-Y. Farm • H. A. Bakar • C. S. Sipaut Energy and Materials Research Group, Materials and Minerals Research Unit, School of Engineering and Information Technology, Universiti Malaysia Sabah, Jalan UMS 88400, Kota Kinabalu, Sabah, Malaysia e-mail: rfmansa@ums. edu. my

R. Pogaku and R. Hj. Sarbatly (eds.), Advances in Biofuels, 219

DOI 10.1007/978-1-4614-6249-1_13, © Springer Science+Business Media New York 2013

13.1 Introduction

Bioethanol (ethyl alcohol, grain alcohol, CH3-CH2-OH or ETOH) is produced from biomass by the fermentation of available carbohydrates, usually simple sugars, into bioethanol and carbon dioxide, via the following chemical process (Harun et al. 2010):

image109(13.1)

Sabah has numerous species of seaweeds. Among these species, Eucheuma spp. is one of the most abundant species along the coastal area. The seaweeds cultiva­tion industry is growing from less than 5,000 tonnes in the year 1985 to more than 110,000 tonnes in the year 2005. The main producers are the Philippines, China, Indonesia, Malaysia (Sabah), Tanzania and Kiribati (Goh and Lee 2010). Seaweeds have different life cycle from terrestrial plants. The rapid growth of macroalgae offers vast harvesting amount in a single planting. They are more productive than other crops as more than five harvests can be obtained in a year. The ability to obtain numerous harvests from a single planting significantly reduces average annual costs for establishing and managing seaweeds, particularly in comparison to conventional crops. In addition, seaweeds flourish in salty water with sunlight and some simple nutrients from seawater. They do not need any chemical fertilisers. Large amount of energy and money is saved from fertilisation. This characteristic improves the sustainability of macroalgae-based third-generation biofuels. In gen­eral, seaweeds can be adapted to live in a variety of environmental conditions.

The potential of macroalgae as fermentation feedstock depends on its carbohy­drate and cellulose. These are the potential fermentation material for ethanol production. Table 13.1 shows the nutrition content of Eucheuma cottonii. Other than carbohydrate, small amounts of cellulose were also detected in the biomass. Fibrous content of E. cottonii can also be broken down to glucose by hydrolysis. Fibrous content includes crude fibre, soluble fibre, insoluble fibre, and total dietary fibre. This accounts for the major part of the seaweed.

Подпись:

image111 Подпись: 9.76 ± 1.33 1.10 ± 0.05 46.19 ± 0.42 5.91 ± 1.21 26.49 ± 3.01 10.55 ± 1.60 18.25 ± 0.93 6.8 ± 0.06 25.05 ± 0.99

Eucheuma cottonii

Third-Generation Biofuels

MPOB is collaborating with University of Malaya on exploring possibility of culti­vating algae in POME ponds which provide nutrients for growth. POME also pro­vides major sources of CO2 essentially required by algae for growing. Some promising strains were obtained with high lipid and biomass contents (unpublished data).

Cultivation of algae either in POME ponds or other potential sites will face issues and challenges concerning methods for efficient, cost-effective mass-production systems, harvesting and processing. In addition, viable technology for lipid extrac­tion and conversion to produce quality fuels is to be sought after.

To move forward, a consolidated effort in setting up and executing Algae Biofuel Consortium, National Algae Culture Collection Facility and National Algae Genomics and Genetics Facility is required from all relevant parties.