Journal of Sustainable Bioenergy Systems, 2013, 3, 217-223
http://dx.doi.org/10.4236/jsbs.2013.33030 Published Online September 2013 (http://www.scirp.org/journal/jsbs)
Prospects of Synthetic Biodiesel Production from Various
Bio-Wastes in Jordan
Ahmad Al-Rousan1, Anas Zyadin2*, Salah Azzam1, Mohammed Hiary1
1National Energy Research Center, Amman, Jordan
2School of Forest Sciences, University of Eastern Finland, Joensuu, Finland
Received July 24, 2013; revised August 25, 2013; accepted September 5, 2013
Copyright © 2013 Ahmad Al-Rousan et al. This is an open access article distributed under the Creative Commons Attribution Li-
cense, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
ABSTRACT
The main objectives of this technical experiment are to quantify the amount of various bio-wastes available for the bio-
energy development in Jordan and investigate the prospects of biodiesel potentials from such bio-wastes using catalytic
depolymerization technology developed in the German company ALPHAKAT. The quantification process revealed
substantial quantities of bio-wastes originated from various sectors such as dairy and poultry farms, by-products of
wastewater treatment plants, and agriculture by-products. The results show that olive cake provides the highest potential
for biodiesel production with a ratio of 39%. Chemical analysis showed varying levels of sulfur contents, which re-
quired desulfurization unit to produce standard quality biodiesel. Chemical analysis also showed high phosphorus con-
tent, which provided another economic opportunity to use the biodiesel by-products as a fertilizer. The statistical corre-
lation test showed a strong linear correlation between the percentage of organic content and caloric value and biodiesel
output. The study also unveiled that the C:H ratio is strongly correlated with the biodiesel production model. The re-
gression analysis generated a model for biodiesel production, which can be used to evaluate the biodiesel production
based on the net dry biomass and C:H ratio in the substrate. Based on the model, the study estimated the potential of
biodiesel from olive cake to reach up to 4 million liters annually. Policymakers and involved governmental institutes are
advised to develop new regulations and laws to increase the share of bioenergy in the primary energy mix through at-
tracting co-public investments accompanied by supportive economic tools such as starter loans, tax exemptions, and
feedin-tar iffs. F ur ther research is ne eded to quantify other sources of bio-wastes such as cooking-oil wastes.
Keywords: Synthetic Biodiesel; Olive Cake; Depolymerization; Jordan
1. Introduction
Bioenergy has been increasingly viewed as a quintessen-
tial tool to produce environmentally-friendly energy to
help mitigate climate chang e and improve the livelihoo ds
of poor people [1-3]. This approach is of particular im-
portance if bioenergy embraces the utilization of bio-
wastes from various human’s end-use sources into usable
forms of energy for transportation purpose. The recently
resonated opposition to bioenergy is deeply-rooted and
largely explained by the use of edible crops such as
maize or sugar cane or the use of edible plant oils su ch as
date palm to produce first-generation biofuels for trans-
portation use in the US, Brazil, and the European Union
(EU). Edible oils and edible crop-based biofuels (bioetha-
nol, biodiesel) were obstinately perceived to jeopardize
staple food production and thus do not meet the prede-
fined sustainability criteria’s especially in developing
countries [4-6]. However, landfill-destined, post-con-
sumer, forests procurement and agriculture by-products
bio-wastes are more appealing and widely supported by
policymakers and the scientific community worldwide
[1,3,7]. Proponents of bioenergy predominantly perceive
it as a carbon-neutral, policy tool to encourage energy
diversity, security and independence, and an attractive
socio-economic tool to enhance rural livelihoods [1-3]. It
presently contributes approximately 10% of global pri-
mary energy supply whilst the traditional use of biomass
for cooking, space heating, and lighting presently ac-
counts for roughly 80% of t he gl obal bi oener gy use [1] . In
the European Union (EU), the consumption of biofuels in
transportation is continued to increase, albeit at a slower
pace, standing at 14 million tons of oil equivalent (Mtoe)
with biodiesel and is the prime biofuel used followed by
bioethanol [8]. Globally, annual biodiesel production in-
*Corresponding a uthor.
C
opyright © 2013 SciRes. JSBS

A. AL-ROUSAN ET AL.
218
creased from 15 thousand barrels per day in 2000 to 289
thousand barrels per day in 2008 [9]. Biofuels are pri-
marily prescribed and ultimately used for transportation
use. The transportation sector is the second largest en-
ergy consuming sector thus responsible for the lion-share
of green-house gases emissions worldwide. Furthermore,
the projected increase in the number of cars per 1000
capita, especially in the Middle East and China and the de-
mand for fossil-derived energy in this sector are expected
to more than double with anticipated staggering levels of
road emissions [10]. In this and other veins, developing
new strains of low-carbon fuels and from biosources is
an unequivocal policy approach to curb emissions, re-
duce urban pollution, and ultimately localize energy
production [3]. Modern bioenergy processes and tech-
nologies have gained innovational stampede accompa-
nied by scientific impetus to produce new energy carriers
such as biohydrogen, bioethanol, biodiesel, and biogas to
meet, at least partly, the growing demand for energy
[1,3,11,12]. Biodiesel or FAME (fatty acid methyl esters)
is simply defined as a chemically modified diesel-like
fuel produced from mainly non/edible plant oils, micro-
algae, and animal fat through a series of chemical reac-
tions using alcohols in the presence or absence of
chemical catalysts [12-16]. Due to the naturally-occur-
ring high viscosity, low volatility, and polyunsaturated
characters of plant oils used in biodiesel production, a
number of chemical processes are developed of which
transesterfication is mostly used and preferred. Trans-
esterfication requires the use of methanol or ethanol in the
presence of catalysts to produce fatty acid esters and gly-
cerol. Basically, it transforms long and branched tri-
glyceride molecules into smaller esters. Other processes
are used to overcome such difficulties involving blend-
ing/dilution, micro-emulsification, heating/pyrolysis,
thermal cracking, and magnetically stabilized fluidized
bed reactor [13-16]. Two other processes to produce bio-
diesel include Fischer Tropsch technology, which is cur-
rently used to convert synthetic biogas into biodiesel.
The other process is the catalytic depolymerization proc-
ess. Depolymerization is a process for the reduction of
complex organic materials into light crude oil. It mimics
the natural geological processes thought to be invo lved in
the production of fossil fuels. Under pressure and heat,
long chain polymers of hydrogen, oxygen, and carbon
decompose into short-chain petroleum hydrocarbons with
a maximum length of around 18 carbons [17]. The proc-
ess is also used to depolymerize complex polymers such
as polyethylene and lignin [14,18]. Biodiesel has a num-
ber of advantages over conventional diesel. Essentially if
it is produced from non-staple food crop s, if it is used as
a complement to other energy sources, and if the plant
oils or energy-dictated crops are grown on set-aside or
degraded lands [1,3,9], it is also imperative to pacify or,
preferably, overcome negative publicity through elevate-
ing public awareness and knowledge of bioenergy and its
benefits [19]. The production and use of biofuels are an-
ticipated to increase in the coming decades through using
increasingly sophisticated processes [3,11]. Therefore,
cultivating greater attention to locally produced biodiesel
and from local bio-wastes is an attractive policy and a
future planning strategy. Jordan is a relatively small
country centered in the heart of the politically instable
Middle East and refered to as the Near East. Jordan lacks
the prime natural resources mainly fresh renewable water
resources, forests, and possesses trivial convention al fos-
sil fuel resources. Consequently, energy for domestic and
industrial purposes is predominantly fueled by permanent
import of fossil fuels (crude oil) from neighboring coun-
tries particularly from Iraq and Saudi Arabia, and Natural
Gas (NG) from Egypt [20]. The negative repercussions
of the high oil prices and subsidies, population growth
and the influxes of refugees, political instability, and
poor planning have led to the paralyzed economy char-
acterized by chronic energy crisis and alarming public
debt. On the other hand, the public is obstinately oppos-
ing building nuclear power plan t yet they exhibit po sitive
attitudes toward harnessing local renewable energy and
bioenergy resources [21]. The Jordanian government has
set a road map for the development and deployment of
renewable energy to increase its share in the primary
energy mix from 7% in 2015 up to 10% in 2020 [20].
While several demonstration projects in solar and wind
energy are currently taking place, however, utilization of
the local bio-wastes is currently underdeveloped. There-
fore, this paper will discuss the economic and techno-
logical side of testing six substrates of different organic
raw materials from Jordan using the catalytic deploy-
merization process by using innovative technology in
Germany known as ALPHAKAT. The main objectives
of this search are:
1) To identify an d quantify the bio-wastes resources in
Jordan;
2) To conduct lab analysis for the biodiesel characteris-
tics from such identified source;
3) To investigate the economic potentials of producing
biodiesel from local resources.
At the policymaking level, th is paper will assist stake-
holders, decision makers, and investors to make sci-
ence-based decision for establishing innovative and pilot
bioenergy projects in the future. This technical paper can
also be considered as a baseline study for researchers in
the field of bioenerg y in Jordan.
2. Methodology
This research project has been implemented in many
stages. In the first stage, a survey of all organic wastes

A. AL-ROUSAN ET AL. 219
types and potential quantities in Jordan has been con-
ducted. The bio-wastes potentials were estimated by
contacting the relevant institution s and labor associations
directly involved production operations such as the Poul-
try Producers Association, Fruits and Vegetables Pro-
ducers and Exporters Association, Dairy Cattle Associa-
tion, and some governmental institutions such as Minis-
try Agriculture. Geographical distribution was also per-
formed through Geographical Information System (GIS)
to generate biomass maps. After bio-wastes being identi-
fied and quantified, six organic wastes were selected for
testing biodiesel production. These substrates are: olive
cake, activated sludge, digested sludge, sheep manure,
poultry manure, and laying hens manure. These sub-
strates were selected according to the physical and logis-
tic aspects such as: high potential, ease of collecting, ease
of cleaning and grinding, ease of drying, and the mois-
ture content. Chemical analysis for the selected organic
materials involved testing cellulose, hemi-cellulose, and
lignin contents. Other parameters were identified for the
selected substrates such as moisture content, organic ma-
terial content, H:C ratio, and percentage of caloric value.
Due to the lack of biodiesel produ ction and testing facili-
ties in Jordan, a number of samples were prepared and
packaged to be shipped to Germany for testing synthetic
biodiesel potentials and quality. Synthetic diesel quality
was later compared to quality standards for fuel in dif-
ferent markets and for different end-users (e.g. EN 590
the European standard for transportation diesel). During
the preparation of the samples for shipping and according
to the European Commission (EC) regulations, the re-
search team acquired sterilization certificate for the ani-
mal organic wastes, health certificate from the Ministry
of Agriculture/Department of Veterinary and Phytosani-
tary Department, and exporting and importing licenses
for the sample packages. Regarding statistical analysis,
t-test was performed to investigate correlation relation-
ships among the study variables followed by linear re-
gression analysis to model th e biodiesel production.
ALPHAKAT Technology
ALPHAKAT machine is a German patent and developed
to produce synthetic biodiesel using catalytic depoly-
merization process. The catalyst used was developed and
patented by Dr. Christian Koch. The machine is pre-
heated with 350 kg of thermo-oil and 30 kg of calcium
hydroxide Ca(OH)2. The process of pre-heating takes
approximately 2.5 hours. The machine is heated in 2
main points: Mixer heat at 180˚C and the Reactor heat
should arrive to 250˚C. As the required temperature is
achieved, organic materials and calcium hydroxide are
inserted through the feeder through conveyor tube, which
delivers the materials to the mixer where the organic
substrates and the thermo-oil as well as the calcium are
well mixed. The function of calcium hydroxide has two
main effects: 1) It reacts with the chloride in the organic
substrate and becomes neutralized and 2) It reacts with
other elements in the substrates to create the optimal
catalyst for the reaction—such as calcium aluminum
silicate. The mixed material is transferred through a tube
to the reactor at (230 - 300)˚C and there a reaction oc-
curs at 1/10 of a millisecond. Organic material is de-
polymerized and turns into gas molecules where carbon
and hydrogen are converted into biodiesel gas. All gases
are transferred to the distiller column to be cooled and
separated at different temperatures. The biodiesel gas
flows through a separate pipe and condense into bio-
diesel liquid, which accumulates in the biodiesel tank.
The H2O gas is separated after condensation and flows
into a separate tank.
3. Results and Discussion
Table 1 shows the estimated q uantities of organic wastes
in Jordan. As indicated, there is a g reat potential for bio-
energy production in Jordan, whether for biogas or bio-
diesel prospects. The largest available bio-wastes quanti-
ties stem from the municipal solid wastes, however, these
wastes are not sorted, rendering utilization a difficult
approach at the moment. Therefore, developing landfill
sorting techniques would encourage the utilization of
such underdeveloped quantities. Jordan has made a tan-
gible progress in developing new wastewater treatment
(WWT) plants using activated sludge process [22].
Therefore, the available quantities of bio-wastes are in-
creasing steadily and provide a great potential for bio-
energy development pro spects. The traditional “stabiliza-
tion ponds” for municipal liquid wastes still exists in
Jordan; therefore, they provide another opportunity to
develop bioenergy projects with vast environmental and
economic benefits. The biggest challenge to bioenergy
development in Jordan is the scattered wastes across the
country especially regarding bio-wastes from animal
husbandry and farming (sheep , dairy cattle and beef) and
poultry production farms. The “All in all out” approach
means centralizing all production facilities of poultry
production in one locatio n and that lo cation is establish ed
away from residential areas, which centralizes the bio-
wastes in one utilizable location. In this prospect, en-
couraging large farms to develop methods of u tilizing the
available bio-wastes into usable forms of energy is an
attractive policy and developmental approach, which
reduces the costs of production by generating part of the
energy needs. Olive cake and vegetables cropping resi-
dues are currently underutilized quantities thus need to
be targeted and included in future bioenergy develop-
ment plans. Olive cake is presently processed and
pressed to produce briquettes for space heating or char-
oal-like product for grill use. When conducting the c

A. AL-ROUSAN ET AL.
220
Table 1. Estimated organic wastes quantities from various sectors and description of the tested samples.
Organic waste category Sub-category Organic m atter (ton DM/ year)No of samples2Quantity shipped (ton) Physical status
Animal husbandry
Sheep manure 8282 2 1.5 Dried & milled3
Beef farms manure 10,036 -
Dairy cattle manure 113,507 -
Poultry manure 50,150 3 2.25 Dried & milled
Laying hens manure 47,661 3 2.25 Dried & milled
Wastewater (sludge)
Activated sludge 87,383 3 2 Dried & milled
Digested 30,801 3 2 Dried & milled
Municipal solid wastes MSW 137,534
Agro-food Olive cake 47,203 2 1.5 Dried & milled
Agriculture and forestry Grain crops residues1 40,000 -
vegetables crops residues 60,000 -
Forests 400 3 2 Dried & milled
1Used only for sheep and goat grazing during summer time and crop rotation-mostly rainfed thus quantities varies considerably; 2The packaged sample that
were shipped to Germany; 3To less than 0.2 mm particle size.
chemical analysis, it was assumed that the chemical
compounds and the production efficiency are correlated.
The percent of organic matter combined with the H:C
ratio is indicative of the Syn-diesel production potential.
The H:C ratio is strongly dependent upon the relative
percentages of lignin (ADL), cellulose (CEL) and Hemi-
cellulose (HC), which forms the Total Crude Fiber (TCF).
Neutral Detergent Fiber (NDF) is made up of four main
chemical components. Quantitatively the largest, cellu-
lose and hemicellulose, the other main components of
NDF are lignin and cutin. Acid Detergent Fiber (ADF) is
basically NDF without the hemicellulose, which can be
removed by boiling NDF in acid detergent solution. Ta-
ble 2 shows the results of the chemical analysis for five
selected substrates. As indicated, olive cake obtained the
highest caloric value, and therefore contains the largest
amount of energy potential. Digested sludge, on other
hand, showed low organic value, and clearly low NDF
fraction, therefore results in low calorific value and low
energy potential. Furthermore, animal derived substrates,
such as sheep and chicken manure, obtained high ener-
getic values because they contain relatively high organic
fraction, however contains low potential for biodiesel
production due to the low NDF fraction. Further chemi-
cal analysis was conducted to investigate the concentra-
tions of approximately 31 minerals. Table 3 shows the
results of some selected minerals with considerable im-
portance to this study. The olive cake showed the highest
concentrations of carbon and hydrogen compared the rest
of organic bio-wastes. Sludge materials (activated & di-
gested) showed highest concentrations of sulfur com-
pared to the rest of biowastes. Olive cake on the other
hand, showed the lowest concentration of sulfur. These
high levels will be taken into account, when evaluating
the final cost of the Syndiesel product. A desulfurization
unit is therefore needed to eliminate the high levels of
sulfur to adjust to EU590 Bio-Diesel standard. This will
add further costs to produce standardized biodiesel up to
5%. Regarding the elements requ ired for the fo rmation of
the catalyst. The concentrations of aluminum (Al), cal-
cium (Ca) and silicate (Si) are in sufficient amount for
the formation of Calcium-aluminum-Silicate. The high
phosphorus concentrations are indicative for the potential
use of the biodiesel by-products as an agricultural fer-
tilizer.
The final stage of this study is to evaluate the biodiesel
potential from each of the selected substrates. As indicated
by Table 4, olive cake showed the highest potential for
biodiesel production. The rest of organic bio-wastes
showed relatively lower potential of biodiesel potentials.
These results can be explained by the high concentration
of carbon and hydrogen in both olive cake and agriculture
residues. As mention earlier, olive cake resources are cur-
rently scattered and underutilized; therefore, such source
provides greater potential for biodiesel production in Jor-
dan. Municipal solid wastes were excluded from the

A. AL-ROUSAN ET AL. 221
Table 2. Chemical analysis of bio-wastes substrates.
Type of biowaste Caloric valueDry matter (%) Organic matter (%)Ash (%)ADF (%)NDF (%)ADL (%) HC (%) CEL (%)TCF (%)
Olive cake 4553 94.1 93.6 6.4 57.1 63.8 25.9 6. 6 31.2 63.7
Digested sludge1 1696 89.5 23.5 42 10 24.1 1.8 14.1 8.2 24.1
Sheep manure 3007 93.9 53 47 29.4 51 13.2 21.6 16.2 51
Laying hens manure 2797 95.6 69.5 30.5 21.3 44.2 4.8 22.9 16.5 44.2
Poultry manure 3312 92.1 84.3 15.7 22.3 45.8 5.5 23.5 16.8 45.8
1Activated s ludge assumed to have similar chemical composition to digested sludge in terms of organic matte r content.
Table 3. Selected minerals concentrations in selected bio-wastes (mg/Kg dry matter).
Element Olive cake Activated sludge Digested sludgeLaying hens manureSheep manure Poultry manure
Phosphorus 3795.0 11493.0 15778.0 19500.0 7512.0 16548.0
Sulfur 3436.0 8026.0 10782.0 4410.0 4300.0 6480.0
Calcium 23780.0 56020.0 163600.0 95500.0 43220.0 30860.0
Aluminum 1535.0 4500.0 6733.0 319.0 2500.0 783.0
Silica 123.0 224.0 222.0 123.0 253.0 289.0
Table 4. Synthetic diesel quantity and percentage fr om various substrates usin g c atalytic depolymerization.
Type of biowaste Input am o un t (K g ) Diesel output
(Liter) Mixer temp (˚C) Reactor temp (˚C) Catalyst (Ca(OH)2) Kg Diesel output (Kg) Diesel output (%)
Olive cake 72.5 34.5 197 280 2.81 28.29 39.02
Activated sludge 30.3 5.5 180 225 1.5 4.51 14.88
Digested sludge 29 4.5 200 240 1.5 3.69 12.72
Sheep manure 30 5.3 190 235 1.5 4.346 14.49
Laying hens manure 31 5.4 192 220 1.5 4.428 14.28
Poultry manure 30 5.5 180 262 0.8 4.51 15.03
1Catalyzer inserted i n th e beginning of the process = 30 Kg; 2Thermo oil inserted in the beginning of t h e proces s = 350 Kg.
process of biodiesel production due to difficulties to sort
and mechanically prepare it for analysis. It also contains
other waste materials such as plastics, metals, and broken
glasses. The correlation and linear regression tests were
deployed using SPSS statistical package to reveal links
between the study variables and the production of bio-
diesel and generate a regression model based on the
analysis. The results showed that under 85% organic
content, there is a strong linear correlation between the
percentage of organic content (R2 = 0.677) and caloric
value (R2 = 0.893) and the biodiesel production from a
given substrate. However, above 85% organic content the
production of biodiesel is affected by the C:H ratio in the
organic matter (R2 = 0.607), which is highly correlated to
the NDF in the organic substrate. Plant-derived organic
substrates contain high NDF thus high C:H ratio, which
increases the biodiesel potential. In order to obtain the
final correlation equation between the organic substrate
and the biodiesel output, a conversion of the original
material into the dry organic material was calculated as
follow:
Net Organic Dry mass = (%) Organic biomass × Dry
matter × (%) Organic matter
The result of the net organic dry mass can be used in
the correlation between C:H ratio and the diesel output as
follow:
y = 0.033x + 0.005
Where: y expected diesel output from single unit (1 Kg)
of the net dry organic biomass, and x is the C:H ratio of
the organic weight.
Table 5 summaries the economic potentials of bio-
diesel production from various biosources. As indicated,
the volume of biodiesel quantities may reach up to 14
million liters, which demonstrates a very attractive in-

A. AL-ROUSAN ET AL.
222
Table 5. Summary of biodiesel production potentials and estimated costs based on the regression model.
Type of biowaste Annual weight of ORM
(ton DM/yr) Total processing cost $US/ton1 Diesel output liters/ton Total diesel output (liters) Processing cost of liter ($US)
Olive cake 47,203 127 475. 0 4,248,270 0.19
Activated sludge 30,801 62 181.5 1,232,040 0.22
Digested sludge 8 7,383 62 155.0 3,495,320 0.26
Sheep manure 8282 78 183.0 455,510 0.30
Laying hens manure 47,661 78 174.0 2,621,355 0.32
Poultry manure 50,150 78 183.0 2,758,250 0.30
1The cost of p r ocessing includes the purchasing cost of raw material (the highe st was for olive cake).
vestment opportunities especially in the light of the cur-
rent fossil fuel prices. The costs of purchasing olive cake
may associate with the higher costs of biodiesel produc-
tion; however, the processing cost of one liter appeared
the lowest.
4. Conclusion
The study indicates relatively high bio-wastes potentials
in Jordan, especially from animal husbandry and farming,
olive cake, and wastewater treatment plants. Municipal
solid wastes provide a potential if sorting techniques are
deployed or household recycling is encouraged. In this
study, olive cake appeared the best option for biodiesel
production while other biosources might be tested for
biogas production. Other sources of biodiesel production
potentially arise from utilizing cooking-oil at the domes-
tic level and particularly in restaurants, which are used in
substantial quantities on daily bases, therefore, further
research is needed to quantify such wastes quantities and
investigate biodiesel production opportunities. In terms
of the policy development, policymakers and the gov-
ernment are encouraged to develop new sets of regula-
tions and laws to navigate the pathway to the bioenergy
development through encouraging private investments
and using economic instruments such as taxexemptions,
starter loans with low interest rates, and issuing distin-
guished bioenergy certificates. More investments in R &
D are required to embark on economic analysis and en-
vironmental impact assessment. Training and outreach
campaigning for large scale dairy and poultry farms to
develop in-site bioenergy production facilities are win-
win approaches with various economic and environ-
mental benefits to the enterprises and the local economy.
At the education level, new lines of bioenergy education
are required to prepare well-trained and educated per-
sonnel to fill-in new employment opportunities in bio-
energy sector. These prospect proj ects can also utilize the
financing tools of climate change such as Clean De-
velopment Mechanism (CDM) and emissions trading
schemes (ETS).
5. Acknowledgements
The authors are indebted to Trilateral Industrial De-
velopment (TRIDE) for the financial support. The au-
thors wish to thank all the Jordanian public institutes for
providing data regarding biomass resources and quanti-
ties in Jordan.
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