A Comprehensive Review on the Industries and Applications Derived From
Petroleum and Coal, And Their Future
Edward Yang
Summer 2011
Section 1: Fuel
A. Alkane
I. Distillation and combustion
CnH2n+2 + (3n+1)/2 O2 → (n+1) H2O + n CO2 + energy
no. of C
1
2
ΔfH (kJ/mol)
-74.9
83.7
ΔcH (kJ/mol)
-802.2
-1596.1
3
-104.6
-2043.1
4
5
-125.5
-146.9
-2657.5
-3271.4
6
-167.4
-3886.2
7
-187.9
-4501
8
-208.4
-5115.8
-91 ~ 98
-51 ~ 126
9
10
-229.3
-249.4
-5730.2
-6345.4
-54 ~ 151
-30 ~ 174
m.p ~ b.p
Uses
-183 ~ -162
-172 ~ -89
Natural gas
Ethylene production
-188 ~ -42
-138 ~ 0
-130 ~ 36
-95 ~ 69
Liquefied petroleum gas
Lab solvents
Gasoline and nonpolar
solvent
Gasoline
The larger the alkane, the higher its melting point and boiling point. In an oil refinery,
different alkanes are distilled and extracted from different sections due to this
difference in boiling point and melting point (fractional distillation). Gaseous methane
will be on the very top, followed by ethane, and so on. The larger the alkane, the more
heat it emits after combustion. The average difference of heat of combustion is about
616 kJ/mol for each additional CH2 group, or each additional carbon atom.
II. Octane rating
Octane rating indicates how much gasoline can be compressed before it
spontaneously ignites. This premature ignition is called engine knock, and it damages
the engine. Isooctane (2,2,4-trimethylpentane) is defined to have a value of 100 on
octane rating, and n-heptane is defined to have a value of 0. The percentage
composition by volume of isooctane and heptane is the octane rating. Gasoline with
an octane rating 90 means it contains 90% isooctane and 10% heptane.
III. Additives
Lead in the form of tetra-ethyl lead (TEL) was once a common additive to boost the
octane rating, that is, to lower the effect of heptane in knocking the engine, but due to
harm lead brings to the environment and its deleterious effect on catalytic converters
(catalytic converters catalyze the reaction that convert carbon monoxide to carbon
dioxide, NOx to nitrogen and oxygen, and hydrocarbon that was not combusted to
carbon dioxide and water), isooctane, MTBE, ETBE, and toluene replaced TEL.
IV. Fischer–Tropsch Process
This is a process that converts a mixture of carbon monoxide to hydrogen (syngas) to
alkanes and water, by the equation (2n+1) H2 + n CO → CnH(2n+2) + n H2O.
Catalysts
In high temperature, iron-based catalysts are more suitable for the production of
methane and alkanes with low molecular-weight, and they can incorporate carbon
dioxide through water-gas shift reaction. In low temperatures, they have a longer
catalyst lifetime. Cobalt-based catalysts can only be useful at lower temperatures, and
it doesn’t utilize water-gas shift reaction. Cobalt catalysts are more active in
synthesizing larger alkanes with the feedstock methane. Alkaline metal oxides act as
promoters to iron catalysts, enhancing activity and selectivity of methane and low
MW alkanes. However, alkaline metal oxides are a poison to cobalt catalysts, causing:
 The activity drop severely
 Selectivity of alkanes with more than 5 carbon atoms and carbon dioxide ↑
 Selectivity of methane, ethane, propane, and butane ↓
 More alkene/olefin form
B. Coal
I. Disadvantages
Ideally, n C + n O2 n CO2 + energy
However:
1. Coal is not entirely carbon; it also contains sulfur:
S + O2 → SO2
2 SO2 + O2 → 2 SO3
SO3 + H2O → H2SO4
The result is the formation of sulfuric acid, a strong and corrosive acid.
2. Air is not entirely oxygen; it also contains nitrogen:
Nitrogen reacts with oxygen to from NOx, either NO or NO2.
2 NO2 + H2O → HNO2 + HNO3
3 HNO2 → HNO3 + 2 NO + H2O
4 NO + 3 O2 + 2 H2O → 4 HNO3
The result is the formation of nitric acid, a strong and corrosive acid.
Under sunlight, NOx also acts as a catalyst to the decomposition of ozone.
2 NO + 2 O3 → 2 NO2 + 2 O2
2 NO2 → 2 NO + O2
Overall reaction: 2 O3 → 3 O2
3. Coal also contains mercury. Overexposure to mercury vapor or its compounds can
occur by absorption through skin, respiratory tract, or digestive tract. Mercury
damages kidneys, heart, and brain. The action of mercury on the brain affects the
nervous system.
II. Clean Coal Technologies
1. Coal washing
The process begins with the grinding of coal into small pieces fed to a barrel
containing fluid. Since different impurities have different density, they float in the
different section of the fluid. Then each layer, containing different substances, is
removed. Coal is purified to be only carbon.
2. Wet scrubbers
The flue gas after combustion contains sulfur dioxide, NOx, and other particulates.
Wet scrubbers remove sulfur dioxide by spraying the flue gas with limestone (CaCO3)
and water to form gypsum, or hydrated calcium sulfate (CaSO4·2H2O).
3. Electrostatic precipitators
Electrostatic precipitators remove small solid particles from flue gas by the force of
an electrostatic charge. These particles could cause respiratory diseases.
4. Gasification
With integrated gasification combined cycle (IGCC), coal is turned into synthesis gas
(syngas), a mixture of carbon monoxide and hydrogen. Hydrogen is a better fuel than
hydrocarbon as discussed later in the paper. The heat generated can be turned into
electricity by a steam turbine. IGCC creates two forms of energy, chemical and
thermal.
C. Hydrogen
I. Why do we need hydrogen?
Today’s energy supply relies heavily on hydrocarbon fuel such as diesel, gasoline, and
natural gas, which are all distilled from crude oil. However, hydrogen fuel has
gradually replaced hydrocarbon fuel in demand of a more sustainable supply.
Hydrogen can be produced from a variety of hydrocarbon feedstocks.
II. From Coal
Coal is first pyrolyzed (broken apart by heat) to remove the impurities. Then pure
carbon is directly treated with steam as such:
C + H2O → CO + H2
This reaction is extremely endothermic, so as heat is absorbed, the original high
temperature will be lowered.
When the temperature is cooled to such that there is not enough activation energy to
start the reaction, air replaces the steam.
Air has to be purified to contain only oxygen.
2 C + O2 → 2 CO
This reaction is exothermic, so as heat is emitted, the temperature will increase. When
temperature is desirable enough for the first reaction to occur, steam is re-injected to
replace air. The cycle goes on until carbon is consumed.
III. Steam Reforming From Methane
Steam reforming is a method of producing hydrogen and carbon monoxide from
methane and steam, or water. The reaction takes place at temperatures as high as 750
to 800°C over a nickel catalyst.
CH4 + H2O → CO + 3 H2 strongly endothermic
More steam is added to carbon monoxide to reduce CO and produce more H2
CO + H2O → CO2 + H2
mildly exothermic, this reaction is called water gas shift
In order to provide such a great amount of heat, the power of sun can also be used.
IV. Steam Reforming From Methanol
Methanol is advantageous over methane for producing hydrogen gas because it is in
liquid form. So it doesn’t need a pressurized gas tank, and there is always more liquid
than gas when they are in equal volume. Water and methanol make contact with the
catalyst and the reaction goes as such:
CH3OH → CO + 2H2
CO + H2O → CO2 + H2 (water gas shift)
V. Separating hydrogen from carbon dioxide
Note that the second reaction is the same for both methanol and methane reforming,
and the products formed are the same, hydrogen and carbon dioxide. There are several
methods to separate these two gases:
 Pressure swing absorption relies on a solid surface. The mixture of gaseous
A and B (generically) goes into a tank. The pressure is increased, and one of
the two gases, A, will try to bind to the solid surface (dependent on which
solid is in application and which gas is desired). So the tank will now be in
lack of A and full of the B. The highly pure gas A comes out of the tank and
stored into a separate tank. When pressure is lowered, gas B will now be
desorbed, coming out of the solid surface. The tank is evacuated, and B is
stored in another tank. A and B are separated.
 A semipermeable membrane such as that used in proton exchange
membrane fuel cell can be used, which only allows hydrogen to pass through
and not any other molecules. Another membrane can also work by having
lots of small pores that are big enough for hydrogen molecules to pass
through but too small for carbon dioxide molecules.
VI. Why carbon monoxide is undesired—carbon monoxide poisoning
CO binds more strongly to hemoglobin than carbon dioxide and oxygen gas. Carbon
monoxide reacts with hemoglobin to form carboxyhemoglobin (HbCO). HbCO is 200
times more stable than HbO2, oxyhemoglobin. So as blood circulates, more and more
HbCO forms, reducing the amount of HbO2. Eventually, cells die from lack of
oxygen.
Section 2: Petrochemicals
A. Ethylene
I. Polymerization
Ethylene polymerizes to form polyethylene (PE). n C2H4 → (C2H4) n
PE is a widely used plastic. It is a thermoplastic, so it can be heated and reshaped.
Annual production exceeds 80 million tons. A variety of different forms of PE have
different properties and thus different applications.
 Ultra high molecular weight polyethylene (MW between 3.1 and 5.67 million)
 used for artificial joints, bulletproof vests, implants, etc
 High density polyethylene (density >= 0.941 g/cm3)
 used in products and packaging such as jugs, bottles, tubs, and pipes
 Cross-linked polyethylene
 used in some potable-water plumbing systems
 Medium density polyethylene (density between 0.926–0.940 g/cm3)
 used in gas pipes and fittings, sacks, shrink film, packaging film, carrier bags
and screw closures
 Linear low density polyethylene (density between 0.915–0.925 g/cm3)
 copolymerized with alpha-alkenes, used in packaging film for bags
 Low density polyethylene (density between 0.910–0.940 g/cm3)
 used for both rigid containers and plastic film applications
 Very Low density polyethylene (density between 0.880–0.915 g/cm3)
 used for hose and tubing, frozen food bags, food packaging and stretch wrap
II. Production of ethanol
Ethanol is produced by the hydration of gaseous ethylene
C2H4(g) + H2O(g) → CH3CH2OH (l) This reaction is catalyzed by phosphoric acid.
Ethanol is a common solvent and a fuel. CH3CH2OH + 3 O2 → 2 CO2 + 3 H2O
Ethanol can also be used as the fuel of direct ethanol fuel cell. At the anode, a
molecule of ethanol meets three molecules of water to give two molecules of carbon
dioxide, twelve protons, and twelve electrons. Protons travel across a semipermeable
membrane Nafion. Electrons travel across the energy output to give power. They then
meet at the cathode with three molecules of oxygen to give six molecules of water.
III. Ethylene oxide
Ethylene oxide is produced by the oxidation of ethylene over a silver catalyst.
2 C2H4 + O2 → 2 C2H4O
Ethylene oxide can be hydrated to form ethylene glycol under 200 °C and 1.5–2 MPa):
(CH2CH2)O + H2O → HOCH2CH2OH.
Or it can react with carbon dioxide first to form ethylene carbonate, and then go
through hydration and decarboxylation, also under 100 °C and 5.2 MPa:
Ethylene glycol is primarily used in engine coolant with water. Since ethylene glycol
is a polyol, it can form polyesters with organic acids.
IV. Vinyl acetate
Ethylene + acetic acid + 1/2 O2 → Vinyl acetate + H2O
Vinyl acetate can be polymerized to form polyvinyl acetate, a major component of
wood glue. Or it can be copolymerized with ethylene to form polyethylene-vinyl
acetate, used as an adhesive and resin. Or it can be copolymerized with vinyl chloride
to form polyvinyl chloride acetate, used in the manufacture of electrical insulation, of
protective coverings, and of credit cards.
V. Vinyl chloride
Vinyl chloride is just like ethylene, but with one of its hydrogen atom substituted by a
chlorine atom. To produce vinyl chloride, ethylene is first chlorinated to
1,2-dichloroethane, catalyzed by iron (III) chloride (FeCl3). Then, hydrogen chloride
is reduced from 1,2-dichloroethane, forming vinyl chloride.
H2C=CH2 + Cl2 → ClCH2-CH2Cl → H2C=CH-Cl + HCl
Vinyl chloride is polymerized to form polyvinyl chloride, or copolymerized with vinyl
acetate as mentioned before. Polyvinyl chloride (PVC) is a commonly used plastic
used for piping, tubing, and many other things.
VI. Ripening of fruit
Ethylene is also responsible for the ripening of fruit because it serves as a hormone in
plants. Plants synthesize ethylene biologically.
B. Propylene
I. Isopropyl alcohol
Isopropyl alcohol is produced by the hydration of propylene.
Indirect hydration, which can use low-quality propylene, involves the catalysis from
sulfuric acid:
C3H6 + H2SO4 → CH3CH2CH2SO4H
CH3CH2CH2SO4H + H2O → CH3CHOHCH3 + H2SO4
Direct hydration requires high-quality propylene: C3H6 + H2O → CH3CHOHCH3
Isopropyl alcohol evaporates quickly and is relatively nontoxic. It is used as an
organic solvent to dissolve oil, clean electronic and optical devices, contact lenses,
and glasses and screens.
II. Acrylonitrile
Acrylonitrile is produced by the ammoxidation of propylene:
2CH3-CH=CH2 + 2NH3 + 3O2 → 2CH2=CH-C≡N + 6H2O
Acrylonitrile polymerizes to form acrylic fibers. End uses include sweaters, hats,
hand-knitting yarns, rugs, awnings, boat covers, and upholstery. It is also used as a
precursor for carbon fiber.
Acrylonitrile also copolymerizes with butadiene and styrene to form ABS
thermoplastic. The chemical formula is (C8H8)x· (C4H6)y·(C3H3N)z. ABS is strong,
rigid, and tough, combining the properties of its three monomers. It is also resistant to
strong acids and bases. ABS is used to manufacture pipe systems, musical instruments,
golf club heads, and automotive bumper bars, and toys, all of each need to be strong.
III. Polypropylene
Polypropylene (PP) is polymerized by propylene over a Ziegler-Natta catalyst. It is
used to make many plastic products that are heat-resistant and rigid. Biaxially
oriented PP sheets can be used as packaging material for retail products.
IV. Propylene oxide
Propylene oxide is produced by oxidation of propylene with hydrogen peroxide, a
process developed by BASF and Dow Chemical in 2009.
CH3CH=CH2 + H2O2 → CH3CHCH2O + H2O
It can undergo hydration catalyzed by sulfuric acid to produce propylene glycol,
which is also used in engine coolant with water and organic solvent.
V. Acrylic acid
Acrylic acid is produced by the oxidation of propylene.
CH2=CHCH3 + 1.5 O2 → CH2=CHCO2H + H2O
Acrylic acid, like all carboxylic acid, reacts with alcohol to form an ester. The most
common esters of acrylic acid are methyl-, butyl-, ethyl-, and 2-ethylhexyl-acrylate.
Acrylic acid polymerizes to form polyacrylic acid. It is capable of adsorbing many
times its weight in water, so it is used in disposable diapers. Acrylic acid also
copolymerizes to form products used in the manufacture of various plastics, coatings,
adhesives, elastomers, as well as floor polishes, and paints.
VI. Allyl chloride
Allyl chloride is produced by the chlorination of propylene. Allyl chloride itself has
little use, so it is converted to other epichlorohydrin in two steps.
Allyl chloride is hydrochlorinated using hypochlorous acid to form two alcohols.
The two alcohols produced are treated with a strong base to form epichlorohydrin.
Epichlorohydrin, with Bisphenol A, is converted to Bisphenol A diglycidyl ether,
which is a precursor to epoxy. Epoxy resins provide a protective layer inside food and
drink cans. Epichlorohydrin is also used to synthesize glycol with simply water.
CH2CHOCH2Cl + 2 H2O → HOCH2CH(OH)CH2(OH) + HCl
However, this process is uneconomical and unnecessary because the glycol produced
from biomass and organic wastes are enough for the world’s supply of glycol.
C. Isobutylene
Isobutylene is produced by the dehydrogenation of isobutane over chromium catalysts:
C4H10 →C4H8 + H2
It reacts with methanol to produce methyl tert-butyl ether (MTBE):
C4H8 + CH3OH → C4H9OCH3
It reacts with ethanol to produce ethyl tert-butyl ether (ETBE):
C4H8 + C2H5OH → C4H9OC2H5
These two chemicals, as mentioned before, are added to gasoline to raise the octane
rating and to reduce carbon monoxide, as they are called oxygenates.
Isobutylene polymerizes to form polyisobutylene (PIB), a component of butyl rubber;
the other component is isoprene. Butyl rubber is added to lubricant to reduce the oil
mist, and fuel to reduce particulate emissions.
D. 1,3-butadiene
1,3-butadiene can be obtained from the hydrocarbons that have 4 carbon atoms by
steam cracking. Butane gives up 4 hydrogen atoms to form 1,3-butadiene.
Over a metal oxide catalyst at 400-450°C
Over a porous silicon dioxide catalyst with tantalum as a promoter at 325-350°C
The function of butadiene is similar to that of isobutylene. It is polymerized and
copolymerized to form a wide range of elastomers such as polybutadiene,
styrene-butadiene rubber, and the plastic ABS as mentioned before. Synthetic rubbers
are made from butadiene and other monomers such as chloroprene, isoprene, styrene,
and isobutylene.
Butadiene goes through Diels-Alder dimerization to form 4-vinylcyclohexene. Two
molecules of butadiene react under a temperature of 110-425°C at pressure of 1.3 100 MPa over silicon carbide and salts of copper or chromium, forming a
cyclohexene with one double bond and a vinyl group (-C2H2) on the fourth carbon
atom from the double bond.
E. Benzene
I. Ethylbenzene
Ethylbenzene is made from reaction between benzene and ethylene in an acid catalyst.
It is mostly converted to styrene through catalytic dehydrogenation.
C6H5CH2CH3 → C6H5CH=CH2 + H2
Styrene is the monomer of polystyrene. In the polymerization process, the double
bonds on the vinyl groups are placed by single bonds, thus making it difficult to
depolymerize. Polystyrene is a thermoplastic and somewhat flexible. It is also
resistant to acids and bases and a good thermal insulator. It can be used in casing and
foam for covering. Polystyrene presents a lot of environmental problems;
hydrochlorofluorocarbons (HCFC) are used as blowing agents to make polystyrene
foams, but HCFC contributes to ozone depletion.
II. Cumene
Cumene is the first intermediate in the cumene process which produces phenol and
acetone from benzene, propylene, and oxygen.
Phenol can be classified as an alcohol because it has a hydroxyl group, but it also
displays weak acidity, as it loses the H+ proton to form C6H5O− phenolate anion.
Phenol tautomerizes itself to form cyclohexadienone, but this reaction is extremely
unfavorable, so phenol rarely exists in cyclohexadienone.
Hydrogenation of phenol produces cyclohexanone, a precursor to nylon.
Phenol and acetone, catalyzed by a strong acid, condense to form Bisphenol-A (BPA).
BPA is a precursor to epoxy resins, as mentioned before.
BPA has another important industrial application; its polymerization with phosgene
(COCl2) produces polycarbonate. It is a thermoplastic and used as water bottles, discs,
cases.
Polycarbonate hydrolyzes to form carbon dioxide and BPA. Biologically, BPA
simulates the activity of the primary female sex hormones. However, it does have
certain negative health effects. It is related to obesity, diabetes, attention deficit
hyperactivity disorder, reproductive health problems, heart disease, and breast and
prostate cancer.
III. Cyclohexane
Cyclohexane is made from hydrogenation of benzene over titanium- and
zirconium-based catalysts. C6H6 + 3 H2 → C6H12
Cyclohexane is converted to a mixture of cyclohexanone and cyclohexanol (KA oil).
Cyclohexanone: C6H12 + O2 → (CH2)5CO + H2O
Cyclohexanol: C6H12 + 1/2 O2 → C6H11OH
Cyclohexanone reacts with hydroxylamine to form cyclohexanoxime and water.
Under acidic conditions, cyclohexanoxime rearranges itself to form
heptagonal-structured caprolactam. This is known as Beckmann rearrangement.
Caprolactam goes through ring-open polymerization to give nylon-6.
The KA oil also goes through a multistep pathway to produce adipic acid, a
dicarboxylic acid with six carbon atoms. It copolymerizes with
hexamethylenediamine, a diamine to give a polyamide, nylon 6-6.
Nylon is the first synthetic fiber; it changes the textile and clothing industry. It is used
as carpet fiber, threads, nets, airbags, tires, ropes, conveyor belts, hoses, clothing,
thread in bristles for toothbrushes, surgical sutures, and strings for acoustic and
classical musical instruments.
IV. Nitrobenzene
Nitrobenzene can be directly produced by the nitration of benzene in an acidic
solution. It has an almond-like odor, so it can be used to mask other unpleasant odors,
such as in shoe and floor polishes, leather dressings, and paint solvents. It is also a
precursor to the production of paracetamol, a medicine for relieving pain and reducing
fever. The larger market of nitrobenzene is the production of aniline. Nitrobenzene
goes through catalytic hydrogenation at 200-300°C to yield aniline and water.
C6H5NO2 + 3 H2 → C6H5NH2 + 2 H2O
Aniline reacts with formaldehyde to form a diamine; this diamine reacts with
phosgene to yield methylene diphenyl diisocyanate (MDI).
MDI copolymerizes with a diol to give polyurethane. Polyurethanes with different
density and stiffness have different uses.
V. Chlorobenzene
It is synthesized by chlorination of benzene, catalyzed by ferric or aluminum chloride.
Chlorobenzene was once used to manufacture dichlorodiphenyltrichloroethane (DDT).
Nowadays it is nitrated to produce various nitrochlorobenzene, then chloroaniline,
nitrophenol, nitroanisole, nitroaniline, dichloronitrobenzene, and
dinitrochlorobenzene, which are all for the production of bactericides, herbicides and
pesticides, and medicine.
F. Toluene
I. Toluene
Toluene is a common solvent used in paints, silicone sealants, rubber, ink, adhesive,
and disinfectants. It can also be used to raise the octane rating. Since it has good heat
transfer capabilities, it acts as a coolant in nuclear reactors.
II. TNT
TNT, trinitrotoluene, is produced by the nitration of one toluene molecule with three
nitric acid molecules. TNT is a well known explosive. It decomposes upon detonation.
2 C7H5N3O6 → 3 N2 + 5 H2O + 7 CO + 7 C or
2 C7H5N3O6 → 3 N2 + 5 H2 + 12 CO + 2 C
Just two moles of TNT can yield up to 20 moles of gas. The pressure and temperature
these gases carry are deadly and destructive.
III. Toluene diisocyanate
Toluene diisocyanate (TDI) is similar to MDI mentioned before. Toluene is nitrated,
then converted to a diamine, and reacted with phosgene to form the diisocyanate
group. TDI copolymerizes with polyols to give polyurethanes, just like MDI, and it
copolymerizes with polyamines to give polyureas.
IV. Benzoic acid
Benzoic acid is produced by the oxidation of toluene, also giving off water. Benzoic
acid is chemical standard to determine the heat capacity of a bomb calorimeter in
measuring the heat of combustion of a reaction. Benzoic acid reacts with sodium
hydroxide to form sodium benzoate. Sodium benzoate is used as a food preservative
to prevent bacterial fermentation of glucose under acidic conditions. The basic
mechanism works like this: when bacterial cell absorbs benzoic acid, the intracellular
pH (pH in the cell) decreases. When the pH is at a value of lower than 5, the
anaerobic fermentation of glucose decreases drastically (by 95%). Therefore, sodium
benzoate can slow down the rate of the ingestion of glucose by bacteria and the
growth of bacteria.
G. Xylene
Xylene is dimethylbenzene, a benzene group connected to two methyl groups. There
are three types of xylene: ortho-, meta-, and para-xylene.
Oxidation using cobalt and manganese catalysts
phthalic acid
(ortho-phthalic acid)
isophthalic acid
(meta-phthalic acid)
terephthalic acid
(para-phthalic acid)
I. Ortho-xylene and phthalic acid
Ortho-xylene undergoes catalytic oxidation to produce phthalic anhydride.
C6H4(CH3)2 + 3 O2 → C6H4(CO)2O + 3 H2O
It undergoes alcoholysis to become a phthalate ester. Most plasticizers are made of
diesters, most notably di-2-ethylhexyl phthalate (DEHP), used in the manufacture of
PVC and other plastics.
C6H4(CO)2O + ROH → C6H4(CO2H)CO2R
C6H4(CO2H)CO2R + ROH → C6H4(CO2R)2 + H2O
II. Meta-xylene and isophthalic acid
Isophthalic acid is a precursor to the fire-resistant polymer Nomex, used as hoods and
masks for firefighters and astronauts. The other component of Nomex is
m-phenylenediamine, and as its name suggests, it is a diamine. When isophthalic acid
copolymerizes with a 3,3',4,4'-tetraaminobipheny, a tetramine, the product is
polybenzimidazole fiber. Its applications include plain bearings, semiconductors,
adhesives, composites, fuel cell membranes, printed circuit boards, and seals.
III. Para-xylene and terephthalic acid
Terephthalic acid esterifies with ethylene glycol form the copolymer polyethylene
terephthalate (PET). PET is used as beverage and food containers, packaging, and
tapes. Biaxially-oriented PET (BoPET) is more flexible and can be metalized to be
used for electronic and acoustic devices.
Section 3: Future
A. Recycling
When petroleum is all consumed, we cannot rely on the crude oil and the hundreds of
different substances it contains. Plastics have to be recycled. Most plastics discussed
are thermoplastic, so they can be reshaped. Directly burning them produces soot, and
they are hard to separate. Ideally though, their combustion produces only water and
carbon dioxide, so technically they can be used as a fuel for generators to generate
electricity.
B. Biodegradable plastics
As the world supply of petroleum decreases, biodegradable plastics deserve more
attention. There are three types of biodegradable plastics, naturally produced,
produced from renewable resources, and synthetic. The benefits of biodegradable
plastics are that not only can they be degraded by microorganisms in the soil, but they
can also be produced by microorganisms without any industrial processes.
I. Polyhydroxyalkanoates (PHA)
Bacillus subtilis produces PHA from malt waste. Ralstonia eutropha produces it from
short-chained hydroxy fatty acids. Pseudomonas putida produces it from long-chained
hydroxy fatty acids. The feedstock can simply be vegetable oil and carbohydrates, and
Micromidas Inc. is working on a method of producing PHA from municipal waste
water. PHA can substitute some plastics in many applications. A new material itself, it
also offers new applications, such as in tissue engineering. PHA has been utilized to
develop devices like sutures, suture fasteners, meniscus repair devices, rivets, tacks,
staples, screws, bone plates and bone plating systems, surgical mesh, repair patches,
slings, cardiovascular patches, orthopedic pins, adhesion barriers, stents, guided tissue
repair/regeneration devices, articular cartilage repair devices, nerve guides, tendon
repair devices, atrial septal defect repair devices, pericardial patches, vein valves,
bone marrow scaffolds, meniscus regeneration devices, ligament and tendon grafts,
ocular cell implants, spinal fusion cages, skin substitutes, dural substitutes, bone graft
substitutes, bone dowels, wound dressings, and hemostats
II. Polylactic acid (PLA)
Bacterial fermentation produces lactic acid from carbohydrates. Two molecules of
lactic acid dimerize to form lactide, a diester. Lactide then goes through ring-open
polymerization to give PLA. PLA can substitute plastics used for food packaging. It is
also used as a material for tissue engineering.
III. Polyvinyl alcohol
Polyvinyl alcohol is produced by the hydrolysis of polyvinyl acetate as mentioned
before. It can be converted to polyvinyl nitrate via nitration, polyvinyl acetals from
aldehydes. It has good emulsifying and adhesive properties, so it can aid emulsion
polymerization, incorporating the monomers, water, and surfactant.
C. Biodegradable plasticizer
Most biodegradable plasticizers are made of glycerides and citrates. They are made
also so that they have little biochemical effects on human body. For example,
acetylated monoglycerides, made of glycerol and fatty acids, can be used as a food
additive, and it is easily digested once it enters the body.
Almost all citrate-based plasticizers are compatible with PVC, thus they can substitute
phthalates. Hydrogenation of diisononyl phthalate produces 1,2-Cyclohexane
dicarboxylic acid diisononyl ester (Hexamoll DINCH), a much more biodegradable
plasticizer.
D. Alternative ways of production
I. Hydrogen
The production of hydrogen cannot solely rely on the supply of hydrocarbon. It can
also be produced by the electrolysis of water: 2 H2O → 2 H2 + O2. This reaction
requires a great deal of energy. Sulfur-iodine cycle is instead applied.
Iodine gas is first reacted with sulfur dioxide and water to form hydrogen iodide and
sulfuric acid, with a temperature of 120°C:
I2 + SO2 + 2 H2O → 2 HI + H2SO4
Sulfuric acid then breaks down into sulfur dioxide, water and oxygen gas, with a
temperature of 830°C:
2 H2SO4 → 2 SO2 + 2 H2O + O2
At last, hydrogen iodide breaks down into hydrogen gas and iodine gas, with a
temperature of 450°C:
2 HI → I2 + H2
Overall reaction: 2 H2O → 2 H2 + O2
Sulfuric acid is massively produced every year, and it is only used as a catalyst in this
reaction. So it can be recycled and reused.
II. Ethanol
A species of yeast, Saccharomyces cerevisiae, is responsible for the fermentation of
sugar in the production of ethanol in alcoholic beverages. Two general reactions are:
C6H12O6 → 2 CH3CH2OH + 2 CO2
C12H22O11 + H2O → 4 CH3CH2OH + 4 CO2
As shown in the reaction, it requires pure glucose or sucrose. The polymer form of
glucose, amylum (commonly known as starch), has the general formula (C6H10O5)n. It
is a polysaccharide. Two neighboring glucose units are bonded by an oxygen atom,
called a glycosidic bond. So the fermentation first has to start with the hydrolysis of
amylum, or the breaking apart of the glycosidic bond. An enzyme called amylase,
found in yeast and also human saliva, is responsible for this process. Industrially, this
process can be accelerated by treating it with dilute sulfuric acid.
To obtain glucose, cellulose can also be hydrolyzed, either by enzymes or acids.
Cellulose is the main constituent of woods, grass, and plants. But they are not solely
cellulose. They are also made of hemicellulose and lignin. Hemicellulose consists of
some pentoses, sugar with five carbon atoms only, and yeasts cannot ferment them to
make ethanol. Lignin is strongly resistant to chemical and enzymatic degradation. The
removal of lignin, called delignification, had traditionally involved chlorine and
produced chlorinated pollutants. Professor Terry Collins at Carnegie Mellon
University discovered that the tetraamido-macrocyclic ligand (TAML) activators with
hydrogen peroxide in water can substitute chlorinated delignification process. While
TAML technology benefits the paper industry, it also pushes forward the transition of
wasted paper, woods, grass, and other cellulosic biomass into glucose and its
fermentation to ethanol.
III. Ethylene
As mentioned before, ethylene helps the ripening of fruits as it serves as a plant
hormone. Thus, plants biosynthesize ethylene. The synthesis starts with methionine,
an amino acid, and the process is called Methionine Cycle or Yang Cycle. Methionine
is converted S-adenosyl-L-methionine (SAM) through the enzyme SAM synthetase.
SAM is converted to 1-aminocyclopropane-1-carboxylic-acid (ACC) with the help of
ACC synthase. Oxygen reacts with ACC, catalyzed by ACC-oxidase to produce
ethylene. The other byproducts are carbon dioxide, hydrogen cyanide, and water.
IV. Adipic acid
The current production of adipic acid is complex and involves a multistep pathway
involving benzene, cyclohexane, cyclohexanone, and cyclohexanol, or KA oil, as
mentioned before. As the supply of petroleum goes down, this key component of
nylon also faces difficulty. Professor Karen M. Draths and Professor John W. Frost at
Michigan State University discovered a way of making adipic acid using microbes. It
applies the genes of three different species of microbes, Klebsiella pneumoniae,
Acinetobacter calcoaceticus, and Escherichia coli. The raw material, muconic acid, is
hydrogenated to adipic acid.
Bibliography
http://science.howstuffworks.com/environmental/green-science/clean-coal.htm
http://www.getenergysmart.org/files/hydrogeneducation/6hydrogenproductionsteamm
ethanereforming.pdf
http://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/fuel-processor.htm
http://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/fuel-processor2.htm
http://www.greenfacts.org/en/nitrogen-dioxide-no2/index.htm
http://news.bbc.co.uk/2/hi/sci/tech/4468076.stm
http://www.neundorfer.com/knowledge_base/electrostatic_precipitators.aspx
http://en.wikipedia.org/wiki/Standard_enthalpy_change_of_formation_(data_table)
http://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/question90.htm
http://pubs.acs.org/doi/abs/10.1021/om030621b
http://www.ipa-news.com/en/89-0-Catalytic+Converters.html
http://www.anl.gov/PCS/acsfuel/preprint%20archive/Files/45_1_SAN%20FRANCIS
CO_03-00_0129.pdf
http://stoltz.caltech.edu/litmtg/2002/may-lit-9_26_02.pdf
http://www1.umn.edu/news/features/2011/UR_CONTENT_290042.html
http://www.ceresana.com/en/market-studies/plastics/polyethylene-hdpe/
http://www.ceresana.com/en/market-studies/plastics/polyethylene-lldpe/
http://www.ceresana.com/en/market-studies/plastics/polyethylene-ldpe/
http://en.wikipedia.org/wiki/Ethanol
http://www.psrc.usm.edu/mauritz/nafion.html
http://www.che.lsu.edu/COURSES/4205/2000/Farritor/IndustrialPractices.html
http://en.wikipedia.org/wiki/Petrochemical
http://www.basf.com/group/pressrelease/P-09-154
http://www.inchem.org/documents/sids/sids/74851.pdf
http://pslc.ws/macrog/acrylate.htm
http://www.dow.com/glycerine/advantage/index.htm
http://www.epa.gov/oppt/greenengineering/pubs/case_studies.html
http://monographs.iarc.fr/ENG/Monographs/vol60/mono60-13.pdf
http://www.epa.gov/ttn/atw/hlthef/ethylben.html
http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info:doi/10.1289/eh
p.5993
http://www.iupac.org/publications/pac/2003/pdf/7511x2099.pdf
http://www.freepatentsonline.com/4731496.pdf
http://en.wikipedia.org/wiki/Beckmann_rearrangement
http://www.ides.com/articles/design/2008/sepe-part-98.asp
http://www.mcdonough.com/writings/promise_nylon.htm
http://www.the-innovation-group.com/ChemProfiles/Aniline.htm
http://en.wikipedia.org/wiki/List_of_polyurethane_applications
http://en.wikipedia.org/wiki/Polyurethane
http://www.uwlax.edu/faculty/loh/pdf_files/chm313_pdf/Manual_current/chm313_Ex
pt2_bomb.pdf
http://apps.kemi.se/flodessok/floden/kemamne_eng/xylen_eng.htm
http://www.hallstar.com/techdocs/The_Function-Selection_Ester_Plasticizers.pdf
http://en.wikipedia.org/wiki/Phthalic_acid
http://www.hos-tec.com/cms/index.php?option=com_content&task=view&id=13&Ite
mid=16
http://www2.dupont.com/Nomex/en_US/index.html
http://www.epa.gov/gcc/pubs/pgcc/winners/grca02.html
http://tissue.medicalengineer.co.uk/Polyhydroxyalkanoates+for+tissue+engineering.p
hp
http://www.epa.gov/gcc/pubs/pgcc/winners/sba05.html
http://www.micromidas.com/about/tech/
http://whatisthatingredient.com/ingredient.php?id=21
http://www.hexamoll.com/portal/streamer?fid=217037
http://www.hort.purdue.edu/newcrop/ncnu02/v5-017.html
http://pubs.acs.org/email/cen/html/060804150713.html
http://www.ncsu.edu/bioresources/BioRes_02/BioRes_02_3_472_499_Taherzadeh_K
_BioEthanol_Review.pdf
http://www.ncsu.edu/bioresources/BioRes_02/BioRes_02_4_707_738_Taherzadeh_K
_EnzymeBased_Ethanol_Review.pdf
http://www.epa.gov/gcc/pubs/pgcc/winners/aa99.html
http://www.epa.gov/gcc/pubs/pgcc/winners/aa98b.html