Biofuels Flashcards
(70 cards)
1
Q
It refers to liquid or gaseous fuels produced
from biomass through various processes such as fermentation, distillation, or chemical reactions.
A
Biofuels
2
Q
It refers to any organic material, including plants, wood, agricultural residues, and animal
waste, which can be used directly as fuel or converted into biofuels
A
Biomass
3
Q
Advantages of Biofuels.
A
Ability to reduce greenhouse gas emissions,
Renewable,
Reduces dependence on fossil fuels
Job Opportunities
4
Q
Challenges in Biofuels
A
- Land use competition between food and fuel production raises concerns about food
security and price volatility. - Technical and economic
barriers remain, as the scalability and efficiency of advanced biofuel technologies are still being
developed, requiring further research and investment. - Infrastructure compatibility is another consideration, as some biofuels may necessitate modifications to existing fuel systems and engines.
5
Q
The diesel engine was designed by ____, a German engineer in the 1890s.
A
Rudolf Diesel
6
Q
Who discovered biodiesel? Where and in what year?
A
G. Chavanne in Belgium in 1937
7
Q
Coined the term for the technique for the
transformation of vegetable oils for their consumptions as fuels,
A
G. Chavanne
8
Q
The transition to biofuels from gasoline products like kerosene and petrol as primary fuel
sources occurred in the 1860s for _____ and in the early 20th century for _____.
A
oil lamps, motor fuels
9
Q
Who established the world’s first large-scale biofuels production initiative to support national development and energy independence?
A
Germany
10
Q
The primary objective was to
support the French sugar beet industry and reduce excess production of various other crops.
A
French Biofuels Plans
11
Q
Who developed the first practical internal
combustion engine using an explosive liquid fuel.
A
American engineer Samuel
Morey in 1826
12
Q
Who developed a process that used mild acids to penetrate wood chips and hydrolyze cellulose, simultaneously extracting wood starches.
A
Heinrich Scholler
13
Q
A process that used mild acids to penetrate wood chips and hydrolyze cellulose, simultaneously extracting wood starches.
A
Cellulose Hydrolysis Method
14
Q
By the 1980s, large-scale cellulosic biomass processing was estimated to cost approximately _____ per gallon.
A
35 cents
15
Q
The implementing policies supporting the Philippine Biofuels program.
A
Republic Act No. 9367 (RA 9367), also known as the Biofuels Act of 2006
16
Q
Currently, DOE has maintained the ethanol and biodiesel blends at ___ and ___ by volume.
A
10% (ethanol), 2% (biodiesel)
17
Q
refers to the dried coconut kernel or meat from which the oil that is processed to biodiesel is obtained
A
Copra
18
Q
a byproduct of sugar
manufacturing process from sugarcane
A
Molasses
19
Q
Biomass resources that are available on a renewable basis and are used either directly as a
fuel or converted to another form or energy product
A
Feedstocks
20
Q
Bioethanol Feedstocks.
A
- Dedicated Energy Crops – Switchgrass, Miscanthus, Poplar, Willow
- Agricultural Crop Residues – Corn stover, Wheat straw, Rice husks, Sugarcane bagasse
- Algae – Microalgae (high carbohydrate content)
- Municipal Waste – Sorted municipal solid waste (organic fraction)
- Wet Waste – Food waste, Industrial food processing waste
20
Q
Types of Biomass Feedstocks
A
- Dedicated energy crops, are non-food crops that can be grown on marginal land (land not
suitable for traditional crops like corn and soybeans) specifically to provide biomass. - Agricultural crop residues,
which include the stalks and leaves. Examples include corn stover (stalks, leaves, husks, and cobs), wheat straw, oat straw,
barley straw, sorghum stubble, and rice straw. - Forest biomass feedstocks fall into one of two categories: forest residues left after logging
timber (including limbs, tops, and culled trees and tree components that would be otherwise
unmerchantable) or whole-tree biomass harvested explicitly for biomass. - Algae as feedstocks for bioenergy refers to a diverse group of highly productive organisms
that include microalgae, macroalgae (seaweed), and cyanobacteria (formerly called “blue-green
algae”) - Wood processing yields byproducts and waste streams that are collectively called wood
processing residues and have significant energy potential. - Municipal Solid Waste resources include mixed commercial and residential garbage, such as yard
trimmings, paper and paperboard, plastics, rubber, leather, textiles, and food wastes. - Wet waste feedstocks include commercial, institutional, and residential food wastes
(particularly those currently disposed of in landfills)
21
Q
Biodiesel Feedstocks
A
- Dedicated Energy Crops – Oilseed crops (e.g., Jatropha, Rapeseed, Sunflower, Soybean)
- Algae – Microalgae (high lipid content)
- Wet Waste – Used cooking oil, Animal fats, Industrial food processing waste
22
Q
Biogas Feedstocks.
A
- Agricultural Crop Residues – Manure (cow, pig, poultry), Silage maize
- Forestry Residues – Decaying plant material
- Municipal Waste – Organic fraction of sorted municipal solid waste
- Wet Waste – Food waste, Industrial organic waste, Wastewater sludge
23
Q
Syngas Feedstocks
A
- Dedicated Energy Crops – Woody energy crops (Poplar, Willow, Eucalyptus)
- Agricultural Crop Residues – Corn stover, Wheat straw, Rice husks, Sugarcane bagasse
- Forestry Residues – Logging residues, Forest thinnings, Bark and branches
- Wood Processing Residues – Sawdust, Wood chips, Pulp and paper mill residues
- Municipal Waste – Sorted MSW (non-recyclable biomass fraction), Urban wood waste
24
Generations of Biofuels
1. First-generation biofuels come from food crops, using their sugars and vegetable oils.
2. Second-generation biofuels are derived from non-food biomass such as lignocellulosic
materials, agricultural residues, and energy crops grown on marginal lands.
3. Third-generation biofuels, or algae-based fuels, use engineered bioenergy crops for
improved biomass-to-biofuel conversion.
4. Fourth-generation biofuels leverage synthetic biology to enhance CO₂ capture and biofuel
production efficiency.
25
Bioethanol Production.
1. Pretreatment- to disrupt the lignin matrix and increase the
porosity of the biomass, thereby exposing cellulose and hemicellulose for further hydrolysis into
fermentable sugars.
2. Hydrolysis - relies on hydrolytic enzymes such as cellulases and hemicellulases, which catalyze the breakdown of complex carbohydrates into simple sugars like glucose and xylose.
3. Fermentation is the biochemical process in which fermentable sugars derived from
hydrolysis are converted into ethanol by microorganisms.
4. Purification - In distillation, the ethanol-water mixture is heated in a distillation column, where ethanol,
having a lower boiling point (78.37°C) than water (100°C), preferentially vaporizes.
26
Methods of Bioethanol Pretreatment
(1) Physical pretreatment involves mechanical processes such as milling or grinding to
reduce particle size and increase the surface area of the biomass.
(2) Chemical pretreatment, on the other hand, employs acid or alkaline solutions to break
down hemicellulose and partially solubilize lignin.
(3) Biological pretreatment is another promising approach that uses lignin-degrading
microorganisms to break down lignin and
hemicellulose in a mild and environmentally friendly manner.
27
the most widely used microorganism for ethanol fermentation
Saccharomyces cerevisiae
28
S. cerevisiae primarily ferments _____ sugars such as ____ and ____ through the
_____, followed by alcoholic fermentation.
hexose (1), glucose and fructose (2), glycolytic pathway (3).
29
A major limitation of S. cerevisiae is its inability to
efficiently ferment _____ sugars such as _____ and _____, which are abundant in lignocellulosic hydrolysates.
pentose (1), xylose and arabinose (2)
30
Following fermentation, the ethanol concentration in the fermentation broth is typically
low, ranging between _____ by volume.
8–15%
31
Conventional distillation alone cannot yield ethanol concentrations beyond _____ due to the formation of an _____.
95.6 %, azeotrope
32
Dehydration methods
(1) Azeotropic distillation involves adding a third component, such as benzene or
cyclohexane, which alters the volatility of the mixture and facilitates water removal by forming a
separate azeotrope.
(2) Molecular sieves, composed of microporous aluminosilicate materials (zeolites),
selectively adsorb water molecules while allowing ethanol to pass through.
(3) Extractive distillation, utilizes a high-boiling-point solvent, such as
ethylene glycol, to alter the relative volatility of ethanol and water, enabling separation.
33
Biodiesel Production
1. Transesterification is a three-step reaction in which triglycerides are converted into
diglycerides, then into monoglycerides, and finally into glycerol, with each step producing a
corresponding amount of biodiesel (FAME). The reaction is typically catalyzed by homogeneous
base catalysts (e.g., sodium hydroxide NaOH or potassium hydroxide KOH) due to their high
reaction rates and efficiency at ambient conditions. The catalyst facilitates the deprotonation of alcohol, forming a methoxide ion, which then
attacks the carbonyl carbon of the triglyceride, breaking the ester bond and forming FAME and
glycerol.
2. In post-reaction, the mixture contains biodiesel, unreacted alcohol, glycerol, catalyst
residues, and soap (if FFAs were present). The system undergoes phase separation, where biodiesel
(nonpolar and less dense) naturally separates from glycerol (more polar and denser). The crude
biodiesel is then subjected to washing with warm water or acid solutions to remove residual
catalyst and soap. Refining processes, such as vacuum distillation, ion exchange, or membrane
filtration, are employed to meet fuel standards.
34
Most commonly used transesterification.
base-catalyzed transesterification
35
This transesterification is preferred for feedstocks with high free fatty acid
(FFA) content since base catalysts can form soap when reacting with FFAs, reducing biodiesel
yield
acid-catalyzed transesterification
36
a biochemical process that involves the anaerobic digestion (AD) of
organic matter, such as fruit waste, in the absence of oxygen
Biogas production
37
Four Key Biochemical Stages in Anaerobic Digestion
(1) Hydrolysis: Complex macromolecules such as carbohydrates, proteins, and lipids are
broken down by extracellular enzymes into simpler monomers (e.g., sugars, amino acids, and fatty
acids). This step is rate-limiting, especially for lignocellulosic materials with a high fiber content.
(2) Acidogenesis: The hydrolyzed products are further metabolized by acidogenic bacteria
into volatile fatty acids (VFAs), alcohols, hydrogen (H₂), and carbon dioxide (CO₂). This stage is
essential for maintaining the energy supply of subsequent microbial communities.
(3) Acetogenesis: Intermediate products from acidogenesis are converted into acetic acid,
hydrogen, and CO₂ by acetogenic bacteria. Hydrogenotrophic methanogens regulate the hydrogen
concentration in the system to prevent process inhibition.
(4) Methanogenesis: Finally, methanogenic archaea convert acetic acid and hydrogen into
methane (CH₄) and CO₂, which are the primary components of biogas. Acetoclastic methanogens
utilize acetate, while hydrogenotrophic methanogens reduce CO₂ using hydrogen to form CH₄.
38
Transesterification is a _____ reaction
reversible
39
Molar ratio of methanol to triglyceride
6:1
40
Optimal C/N ratio to prevent excess ammonia production
between 20:1 and 30:1
41
Mesophilic
conditions are commonly maintained.
30–40°C
42
Reaction Pathways for Syngas Production
1. Steam Reforming In this process, methane reacts with steam
(H₂O) in the presence of a nickel-based catalyst at high temperatures (700–1,100°C) and moderate
pressures (3–25 bar) to produce hydrogen and carbon monoxide. This reaction is highly
endothermic (ΔH > 0), meaning it requires continuous heat input.
2. Dry reforming involves the reaction of methane with carbon dioxide (CO₂), rather than
steam, to produce syngas with a H₂:CO ratio close to 1:1.
3. Partial oxidation is an exothermic process (ΔH < 0) in which methane reacts with a
controlled amount of oxygen (O₂) to produce syngas. Unlike steam and dry reforming, which
require external heat input, partial oxidation generates intrinsic heat due to combustion, making it
a self-sustaining process.
43
Hydrogen-to-Carbon Monoxide Ratio for Steam Reforming
3:1
44
Hydrogen-to-Carbon Monoxide Ratio for Dry Reforming
1:1
45
Hydrogen-to-Carbon Monoxide Ratio for Partial Oxidation
2:1
46
H₂ from syngas reacts with nitrogen to form NH₃ in ______.
Haber-Bosch Process
47
The elimination of ______ as a gasoline additive has been
mandated due to its harmful effects on the environment and human health.
Methyl Tertiary Butyl Ether (MTBE)
48
To encourage investments in production, distribution, and use of locally produced biofuels,
biofuel producers and investors are exempted from income taxes on revenues generated from
biofuel production and sale for _____ years from the effectivity of the Act.
Seven (7)
49
Biodiesel blend by October 2024
3%
50
Biodiesel blend by October 2025
4%
51
Biodiesel blend by October 2025
6%
52
In the Philippine Energy Plan Report of DOE on both 2020 and 2021, biodiesel and bioethanol each contributed ___ to the Philippines' total energy supply.
0.3%
53
Biodiesel Production Capacity in the Philippines
614.9 Million Liters
54
Located in Quezon City, this biodiesel refinery has a capacity of 90 Million Liters per Year
Chemrez Technologies, Inc.
55
What is the Production Capacity of Tantuco Enterprises Inc?
90 Million Liters Per Year
56
One of the early biodiesel producers started in 2005 in the Philippines
Phil. Biochem Products, Inc.
57
Located in Pasig City, this biodiesel refinery has a capacity of 72 Million Liters Per Year
Pure Essence International, Inc.
58
While the country has a significant biodiesel production capacity,
actual production remains well below its full potential, with capacity utilization ranging between
_____ and ______.
26.6% and 39.9%
59
Currently, the local production cost of ethanol stands at ____
per liter, while imported ethanol costs only _____ per liter
₱79.70, ₱40
60
Main feedstock of Green Future Innovations, Inc.
Sugarcane
61
Main feedstock of Roxol Bioenergy Corp.
Molasses
62
A 40-MLY bioethanol refinery located in San Carlos City, Negos Occidental
San Carlos Bioenergy Corp.
63
the world's largest producer of biofuels, primarily ethanol and
biodiesel
United States
64
This country mandates an E27 blend (27% ethanol in gasoline) under the National Biofuels
Policy (RenovaBio)
Brazil
65
The world's largest bioethanol producer with a capacity of 3 billion liters per year, using corn.
POET (USA)
66
POET (USA) has how many operating plants?
33
67
The world's largest biodiesel supplier producing 2.4
billion liters per year
Wilmar International (Singapore)
68
Primary Feedstock of Wilmar International
Palm Oil
69
Syngas Downstream and Applications
1. Electricity Generation: Syngas can be directly combusted in gas turbines or used in solid
oxide fuel cells (SOFCs) to generate electricity.
2. Fuel Synthesis (Fischer-Tropsch Process): Syngas is converted into liquid hydrocarbons
(synthetic diesel, gasoline, and jet fuel) via Fischer-Tropsch catalysis over iron (Fe) or
cobalt (Co) catalysts at 200–350°C and 20–40 bar.
3. Methanol and Ammonia Synthesis: In the presence of copper-based catalysts, syngas
undergoes methanol synthesis (CO + 2H₂ → CH₃OH) or ammonia production (H₂ from
syngas reacts with nitrogen to form NH₃ in the Haber-Bosch process).
