1ST LONG QUIZ Flashcards
(191 cards)
1
Q
Differentiate hard water with soft water.
A
Hard water contain objectionable amounts of dissolved salts of calcium and magnesium while soft water is free from dissolved salts such as calcium and magnesium.
2
Q
How does ion exchange utilized in water softeners?
A
Ion exchange consists of removing hardness ions calcium and magnesium and substituting them with non-hardness ions such as sodium to be supplied by dissolving sodium chloride salt or brine.
3
Q
Explain how sodium-cation-exchange process works in water conditioning.
A
Large calcium and magnesium ions displace smaller sodium (Na+) ions. The smaller sodium ions are employed to coat an exchange medium (natural “zeolites” or synthetic resin beads resembling wet sand) in the softener during the ion exchange process. When hard water flows through a water softener, calcium and magnesium ions are exchanged for sodium ions. Sodium ions are held loosely and are readily replaced by calcium and magnesium ions, which are bigger. This process results in the release of “free” sodium ions into the water. After the resins are exhausted, they can be returned to their original state and the process can be repeated.
4
Q
Explain how hydrogen-cation-exchange process works in water conditioning.
A
The hydrogen-cation exchange process is quite similar to the sodium cation removal process, with the exception that all cations can be removed using exchange resins because they contain an exchangeable hydrogen ion.
5
Q
What process in ion exchange in water conditioning serves as the most extensively utilized and cost-effective approach?
A
Regeneration with sulfuric acid
6
Q
Explain how anion exchangers works in water conditioning.
A
Anion exchangers are made of two resin kinds, either highly basic or weakly basic, that remove strongly ionized acids, such as sulfuric, hydrochloric, or nitric, and weakly ionized acid types, such as silicic and carbonic.
7
Q
Explain how lime-soda process works in water conditioning.
A
It is quite useful for treating large quantities of hard water. When lime (CaO) and sodium carbonate (Na2CO3) are added to hard water, calcium carbonate, and magnesium hydroxide are precipitated. The required quantities of the two compounds can be simply estimated based on the water analysis and stoichiometry of the reactions. The lime soda method precipitates hardness from solution using lime, Ca(OH)2, and soda ash, Na2CO3.
8
Q
Explain how cold lime process works in water conditioning.
A
It is treated with lime or a mixture of lime and soda ash, which interacts with the hardness and alkalinity of the water to generate insoluble compounds. After the chemicals precipitate in water, sedimentation/clarification eliminates them. It is used when the mineral level of the source water
ranges between 150 ppm and 500 ppm .
9
Q
Explain how hot-lime soda process works in water conditioning.
A
It is similar to the cold lime process, with the addition of steam to the mixed tank. Precipitation is more rapid and utilized exclusively for boilers. Magnesium water hardness can be eliminated entirely, while calcium water hardness may remain at a very low level.
10
Q
Explain how phosphate conditioning works in water conditioning.
A
Scale formation can be avoided in high-pressure boilers by adding sodium phosphate, which interacts with hardness-causing substances in the water to generate a soft, non-adherent sludge of calcium and magnesium phosphates that can be removed via blow down.
11
Q
How phosphate conditioning differs from lime process?
A
Phosphate conditioning involves an internal treatment method while lime process involves an external treatment method.
12
Q
Explain how to remove colloidal and ionic silica in water conditioning.
A
A strong base anion exchange resin is created to reduce ionic silica to parts per billion (ppb) levels. Ionic Silica is a weak acid, which can be removed entirely by a cycle based on hydroxide. The colloidal silica can be removed by a fine mechanical method such as ultrafiltration.
13
Q
It is the removal of dissolved gases from boiler feedwater by mechanical means, to avoid corrosion.
A
Deaeration
14
Q
Chemical process equation for rusting.
A
O2 + Fe + H2O -> Fe2O3H2O
15
Q
How deaeration works in water conditioning.
A
Dissolved oxygen in boiler feedwater causes severe corrosion damage. It adheres to metal piping and other equipment, and it creates oxides (rust). When dissolved carbon dioxide mixes
with water, carbonic acid is produced, which worsens corrosion.
16
Q
It refers to any treatment method that removes minerals from water. However, it is mainly reserved for ion exchange (IX) processes designed to remove ionic mineral pollutants to an almost complete degree.
A
Demineralization or deionization.
17
Q
It is the process of removing soluble salts from water in order to make it appropriate for drinking, irrigation, and industrial applications.
A
Desalination
18
Q
Give two types of desalination techniques.
A
- Membrane
▪ reverse osmosis
▪ nanofiltration
▪ electro-deionization
▪ electrodialysis - Thermal Processes
▪ multiple-effect distillation (MED)
▪ multi-stage flash evaporation (MSF)
▪ vapor compression
19
Q
It is the process of removing undesired chemicals, biological contaminants, suspended particles, and gases from water. The purpose is to create water appropriate for a variety of applications.
A
Water purification
20
Q
Explain how purification works in water conditioning.
A
Physical techniques such as filtering, sedimentation, and distillation are employed, as well as biological processes such as slow sand filters or biologically active carbon, chemical processes such as flocculation and chlorination, and electromagnetic radiation such as ultraviolet light.
21
Q
Enumerate 6 environmental protection throughout the year.
A
(1) London Convention of 1900
- Safeguard African wildlife
(2) 1933 London Convention
- Creating nature parks and protecting species in Africa.
(3) Stockholm Declaration (1972)
- Recognize the right to a healthy environment through 26 principles, many of which had a significant influence in the subsequent development of IEL.
(4) Rio Declaration (1992)
- The Precautionary Principle and Principle 10, which emphasizes the right to information, involvement, and justice in environmental problems.
(5) Kyoto Protocol (1997)
- The first international agreement to impose legally binding responsibilities for industrialized countries
(6) Paris Agreement (2016)
- Agreement that aims to prevent the average global temperature from increasing by more than 2°C relative to pre-industrial levels.
22
Q
In 2020, about how many percent of wastewater in the Philippines is treated?
A
10%
23
Q
How many percent of the total population in the Philippines is connected to a sewer network?
A
5%
24
Q
About how many percent of families in the Philippines have sanitary toilet facilities?
A
76.8%
25
How many percent in the Philippines have access to piped sewerage systems?
10%
26
What are the methods for deactivating dangerous contaminants?
1. Neutralization of acids or bases
2. Oxidation of many chemicals
3. Binding into an impermeable chemical matrix
4. Incineration
5. Pyrolysis
27
What are the common types of equipment for collecting tiny particulates?
1. Baghouse filters
2. Cyclones
3. Scrubbers
4. Electrostatic precipitators
28
How does sludge, one of the industrial solid waste, is treated in industries?
Sludge is dehydrated using centrifugation, filtering, and/or heating.
29
Incineration is banned in the Philippines because of R.A. 8749 or known as?
Clean Air Act
30
It is most widely used solid fuel, the world's largest greatest deposit, low-cost source of heat and power, and can make specific aromatic and aliphatic chemicals.
Coal
31
What are the 5 common procedures for generating chemicals from coal?
1. Gasification
- turns coal into a very hot synthesis gas
2. Liquefaction
- turns coal into liquid products resembling crude oil
3. Direct Conversion
- involves contacting coal directly with a catalyst
4. Co-production of Chemicals
- consists of pyridine, naphthalene, creosote oil, etc.
5. Co-production of Fuels
- burns coal to generate electricity, gasoline, etc.
32
Enumerate 6 types of coal.
1. Peat
2. Lignite
3. Sub-bituminous
4. Bituminous: (1) Smithing coal (2) Cannel coal (3) Coking coal
5. Anthracite
6. Graphite
33
It is not coal, but can eventually transform into coal under the right circumstances. It is an accumulation of partly decayed vegetation that has gone through a small amount of carbonization.
Peat
34
It is the lowest rank of coal. It has carbonized past the point of being peat, but contains low amounts of energy—its carbon content is about 25-35 percent. It comes from relatively young coal deposits, about 250 million years old.
Lignite
35
It is about 100 million years old. It contains more carbon than lignite, about 35-45%. It is also considered "brown coal" along with lignite.
Sub-bituminous
36
It is formed under more heat and pressure, and is 100 million to 300 million years old. It contains about 45-86 percent carbon.
Bituminous
37
Give 3 types of bituminous coal.
(1) Smithing coal
- has very low ash content, and is ideal for forges, where metals are heated and shaped.
(2) Cannel coal
- was extensively used as a source of coal oil in the 19th century. Coal oil is made by heating cannel coal with a controlled amount of oxygen, a process called pyrolysis.
(3) Coking coal
- is used in large-scale industrial processes. The coal is coked, a process of heating the rock in the absence of oxygen. This reduces the moisture content and makes it a more stable product. The steel industry relies on coking coal.
38
It is the highest rank of coal. It has the most amount of carbon, up to 97%, and therefore contains the most energy. It is harder, denser, and more lustrous than other types of coal.
Anthracite
39
It is an allotrope of carbon, meaning it is a substance made up only of carbon atoms and it is the final stage of the carbonization process.raphite.
Graphite
40
How pyrolysis or carbonization works in manufacturing products using coal.
The process of heating coal in the absence of air/oxygen to obtain products (coal tar, coke, coal gas, and ammoniacal liquor) which are determined by the temperature and the type of coal used.
41
What are the two types of carbonization of coal? Differentiate the two.
(1) Low-temperature carbonization
- The yield of liquid products is larger than the yield of gaseous products. Soft coke is obtained and is used for dometic purpose. No smoke is produced.
(2) High-temperature carbonization
- The yield of gaseous products is larger than the yield of liquid products. Hard coke is obtained and is used for metallurgical purpose. Smoke is produced.
42
It is the process of converting coal into a graphitizable substance known as coke.
Coking of coal
43
What are the two main types of coking procedure? Differentiate the two.
(1) Beehive coking
- The old and primitive method of securing coke for metallurgical purposes.
(2) By-product coking
- A method where blended-coal charge is heated on both sides so that the heat travels towards the center that produces shorter and more solid pieces of coke.
44
Explain how beehive coking process works.
The coal is scattered across the floor after being inserted through a hole in the dome. The gases emitted by the coal mix with the air entering through the discharge door at the top and burn. Combustion products exit through the top of the oven.
45
Explain how by-product coke making is operated.
For bulk density control, selected coals are blended, crushed, and oiled. The blended coal is fed into a series of slot-type ovens, each of which shares a heating flue with the oven adjacent to it. The coal is carbonized in a reducing atmosphere, and the off-gas is collected and transferred to a byproduct recovery plant. The hot coke is discharged, quenched, and shipped to the blast surface.
46
Enumerate 5 by-product recovery of coal chemicals.
1. Tar. The gas from the coke oven is sprayed with liquor ammonia in a tower. Tar and dust are gathered in the tank below, which is heated by a steam coil in order to recover the ammonia that has been sprayed.
2. Ammonia. The gases are then sprayed with water as they pass through another tower. Ammonia gets converted to NH4OH.
3. Naphthalene. The gases are sent through another tower, this time with cooled water sprayed on them. The naphthalene is condensed here.
4. Benzene and other aromatic compounds. The gas is then sprayed with creosite oil as it passes through the next tower. The oil is dissolved in benzene and other aromatic chemicals, which are then recovered.
5. Hydrogen sulphide. The gas is then sent through a purification chamber.
47
It is a complex mixture of polynuclear aromatic compounds and a by-product of the coal pyrolysis.
Coal tar
48
Explain how the distillation of coal tar works.
Coal tar is distilled using the fractional distillation method. The process of fractional distillation of tar refers to the separation of components in a chemical mixture using the difference in their boiling points.
* Benzols, naphtha, creosotes, naphthalene, anthracene, carbolic and cresylic acids, pyridine, and pitch are all produced by distilling coal tar.
49
What are the three purpose of tar distillation.
1. dehydrate the tar in the dehydration column
2. remove the pitch from the dehydrated tar in pitch column
3. separate tar oils in fractionating column
50
Flammable gases that burn using air or oxygen to produce heat make up a family of gases.
Fuel gas
51
What are the three classifications of fuel gas? Define each.
(1) Naturally occurring gases
- gases that are extracted directly from natural wells or can be obtained as a product of another process like refining.
(2) Synthesized gases
- mainly manufactured from other sources such as liquids/solid, fuel or water.
(3) By-products
- gases produced mainly after combustion of gases like specific coal processing or utilization reactors.
52
It is a combustible gas consisting of non-hydrocarbons and hydrocarbons and it is a fossil fuel energy source.
Natural gas
53
What are the three classifications of natural gas location?
(1) Conventional gas
- natural gas that can be extracted as it moves into large fractures and crack between layers of overlying rock.
(2) Unconventional Gas
- ‘tight gas’ or ‘shale gas’ that is located within tight pore
spaces and on gas that is trapped on ice on the seafloor
(gas hydrates).
(3) Associated Gas
- gas dissolved in oil; natural gas pressure that is applied to the underground oil reservoir frequently acts as the force
that propels oil to the surface.
54
Where is the major producer of natural gas in the Philippines?
Malampaya gas field in Palawan
55
Explain the 4 steps how natural gas is processed and purified.
(1) Oil and Condensate Removal
- Raw natural gas are dissolve in oil when extracted. The separation of oil and natural gas can be separated on their own due to the decrease in pressure. In most cases, conventional separators use gravitational separation techniques. For some cases, when wells produce high pressure gas and light crude oil or the condensate, LTX or the low temperature separator is employed. This separator utilizes pressure differentials to cool down the wet natural gas and separate the oil and condensates.
(2) Water Removal
- This step requires "dehydrating" the natural gas, which often entails either of the next two procedures - absorption and adsorption. Absorption occurs when water vapor is taken out by a dehydrating agent. Adsorption on the other hand happens when the water vapor is condensed and is collected on the surface of a solid desiccant.
(3) Separation of natural gas liquids (NGLs)
- Natural Gas Liquids (NGLs), which are valuable as separate products, make up a significant portion of natural gas that is obtained directly from a well. When heavier hydrocarbons are present, an absorption method is employed which utilizes NGL absorption tower and solvent regenerator, while when lighter hydrocarbons are presented, cryogenic expansion is utilized which uses mechanical refrigeration and a very low
temperature of gas stream.
(4) Sulfur and carbon dioxide removal
- Removing hydrogen sulfide and other sulfides in a gas is
necessary because it might cause a corrosion problem, but since the oxides of sulfur formed during the combustion process would affect the flow of gas consumers. In addition,
the sulfur compounds, more specifically H2S and S, have an efficient commercial value since these can be employed as a source of SO2 to produce sulfuric acid.
56
Hydrogen sulfide (H2S), which exists as sulfur in natural gas, is typically regarded as sour if it reaches how much mg of H2S per cubic meter of natural gas?
5.7
57
What does "Sweetening" of the gas mean?
It is the process of eliminating carbon dioxide and
hydrogen sulfide from a stream of natural gas using amine solution.
58
Explain how solid bed process works in separating acid gases from natural gas?
This procedure separates the acid gases from the gas stream and traps them in a fixed bed of solid particles.
59
Explain how liquid bed process works in removing hydrogen sulfide from natural gas?
The procedure makes use of a continuous contactor of some kind, like a packed tower or bubble-cap tower, where the gas flows up counter-current to the flow of the solution.
60
What are the two classifications of liquid bed process? Differentiate the two.
(1) Non-Regenerative processes
- utilized when (hydrogen sulfide (H2S) quantities are small or when residual H2S are cleaned after the removal of bulk volume.
(2) Regenerative process
- the purification for this process is affected by scrubbing the gas with a diluted solution of sodium carbonate (3 to 3.5 percent). The treatment removes all H2S, together with any hydrogen cyanide and some CO2 that s present from the gas.
61
It is a synthetic gas that is a combination of combustible gases usually composed of carbon monoxide and hydrogen and methane. It is described as a fuel gas mixture and is a product of the gasification process of a carbon-containing fuel.
Coal gas
62
Enumerate 3 classifications of coal gas.
1. Low-heat-content syngas
- heating value of below 7 MJ/ m3
2. Medium-heat-content syngas
- heating value of between 7 and 15 MJ/m3
3. High-heat-content syngas
- heating value of 37 MJ/ m3
63
It is a thermochemical process of converting carbonaceous material such as a coal into a fuel - such as synthesis gas.
Gasification
64
It is often called blue gas because of the color of the flame when it is burned is used in the production of hydrogen.
Water gas
*Equation: C(amorph) + H2O(g) −−> CO(g) + H2(g)
65
What are the two main elements in producing blue gas?
The "run" and "blow" where the two main elements involved in producing water gas, and they each functioned in turn to create the gas in a cyclical pattern.
(1) During the blow period, air is employed with the use of fans into the base of the fuel bed. This provides oxygen, allowing the fuel to combust and heat the generator.
(2) During the run period, a steam was introduced into the generator to react with carbon. As the run proceeds, the fuel bed started to cool, the carbon dioxide produced and inert substances are increased, reducing the heating quality.
66
It is a type of fuel gas that is produced when air and steam is employed to a heating bed of coal. The focus is towards an incomplete combustion, to maximize the formation of carbon monoxide and minimize the formation of carbon dioxide.
Producer gas
67
is a fuel gas consisting of volatile hydrocarbons and it is a byproduct of the production of both crude oil refining and natural gas processing.
Liquified Petroleum Gas (LPG)
68
What are the 5 properties of industrial gases?
1. Gaseous at room temperature and pressure
2. Low molecular weight
3. Requires proper handling and storage
4. Element, compound or mixtures
5. Distinct chemical properties
69
A measure of how readily a substance undergoes a chemical reaction.
Reactivity
70
Quality of being unreactive with other chemical compounds.
Inertness
71
An important heat-trapping gas, or greenhouse gas, that comes from the extraction and burning of fossil fuels (such as coal, oil, and natural gas), from wildfires, and from natural processes like volcanic eruptions.
Carbon dioxide
72
Chemical reaction for concentrating CO2
Na2CO3 + CO2 + H20 = 2NaHCO3
* = means reversible rxns
73
What do you call the reaction for concentrating CO2 that involves the use of hot, concentrated potassium carbonate solution, and ethanolamine solution?
Absorption Reaction
74
A process in which sugars are transformed into a new product through chemical reactions carried out by microorganisms.
Fermentation
75
Chemical Reaction of Fermentation
glucose (with yeast) -> ethanol + carbon dioxide
76
True or False: A major source for deriving hydrogen is from carbonaceous materials.
True
77
A method that produces high-purity hydrogen (an industrial gas) and consists of passing direct current through an aqueous solution of alkali, and decomposing the water.
Electrolytic Method
78
What is brine electrolysis?
A large scale process used to manufacture chlorine from salt.
79
A process in manufacturing hydrogen, an industrial gas, that consists of catalytically reacting a mixture of steam and hydrocarbons at an elevated temperature.
Steam-Hydrocarbon Reforming
80
Define coal gasification.
A process that turns coal into a very hot synthesis gas or syngas which is composed of carbon monoxide, hydrogen, and carbon dioxide, as well as amounts of other gases and particles.
81
Reversible reaction of ammonia
2NH3 = N2 + 3H2
* = means reversible rxns
82
A method used to remove carbon dioxide from gas mixtures, also referred as "carbon scrubbing".
Hot potassium carbonate process
83
It is an industrial gas that is noncombustible but will actively support the burning of combustible materials.
Oxygen
84
An industrial gas that is a by-product in manufacturing Xenon gas.
Krypton
85
What is the chemical reaction of manufacturing acetylene gas?
CaC2 + 2H2O -> Ca(OH)2 + C2H2
86
3 main forms of carbon
1. Amorphous carbon
2. Graphite
3. Diamond
87
Differentiate fabricated and non-fabricated carbon.
Fabricated carbon represents fabricated amorphous and graphitic carbon while non-fabricated carbon represents lampblack, carbon black, activated carbon, graphite and industrial diamonds.
88
It is a soft, amorphous material formed primarily from soot, produced by incomplete combustion.
Lampblack
89
It is an amorphous noncarbon made from incomplete combustion of various organic metal, characterized by their nearly spherical shape.
Carbon black
90
Differentiate how furnace black is manufactured by oil furnace and gas furnace.
Furnace blacks made by oil furnaces mainly use feed consisting of highly aromatic hydrocarbons while gas furnace process uses natural gas.
91
4 main processes how the feed of furnace black is operated.
1. Atomization, Pyrolization
2. Nucleation
3. Agglomeration
4. Carbonization/dehydrogenation
92
3 main carbon blacks differentiated by manufacturing process
1. Furnace black
- Feed (highly aromatic carbons or natural gas) undergoes atomization/pyrolization, nucleation, agglomeration, & carbonization/dehydrogenation
2. Channel black
- Feed (natural oil) is heated and vaporized near metals to which carbon can stick, soot is removed by scrapers, fans remove excess vapors and lastly, filtration to acquire carbon black suspended in air.
3. Thermal black
- Carbon blacks are produced by thermal decay.
93
It uses natural oil as a feed and also produce carbon black through incomplete combustion.
Channel black
94
Two categories of activated carbon based on size.
1. Granular carbon
- used for vapor adsorption and liquid purification
2. Powdered activated carbon
- used primarily in liquid purification
95
Define activated carbon.
Carbon material with high affinity for adsorption.
96
Explain how activated carbon is manufactured.
1. Carbonization
- The material is heated at high temperature to eliminate oxygen, nitrogen, hydrogen as volatile compounds and increase the concentration of carbon.
2. Activation
a. Gaseous Treatment
- Steam or carbon dioxide is used to remove carbon residue blocking the pores to increase porosity and surface area of the whole carbon.
b. Chemical Treatment
- Chemical impregnating agents (phosphoric acid, zinc chloride)
97
2 Types of Graphite
(1) Natural graphite
(2) Manufactured or artificial graphite
- created by heating a carbonaceous material (petroleum, coal) in temperatures greater than 2400C.
97
2 Types of Graphite
(1) Natural graphite
(2) Manufactured or artificial graphite
- created by heating a carbonaceous material (petroleum, coal) in temperatures greater than 2400C.
98
Out of all of the carbon fiber produced are __% are made out of polyacrylonitrile (PAN), and the remaining __% are of rayon or petroleum pitch.
90%, 10%
99
3 main types of natural diamonds.
(1) Monocrystalline diamonds
- mostly consist of a singular crystal
(2) Fibrous
- consists of numerous microfibers
(3) Polycrystalline
- consists of many small crystallites of differing masses in a single structure.
100
3 Methods of Manufacturing Diamonds.
(1) HPHT Method (high pressure high temperature method)
- Pressures of 5 GPa - 5.5 GPa and temperatures ranging from 1300C-1500C is used. A tiny diamond seed will be put on a container containing molten metal with dissolved carbon to
which it is then pressurized. This environment then results in the growth of the diamond through the carbon in the solution.
(2) Chemical Vapor Deposition
- A diamond seed will be placed inside a vacuum chamber and a carbonaceous compound will be vaporized inside.
The chamber will then be heated to a temperature of about 700C-1316C to which the carbon vapor will be turned to plasma. Carbon is released and is deposited into the surface of the diamond which will result in the growth of the diamond.
(3) Detonation Method
This method uses explosives in order to create a shockwave to create pressures ranging from 20-35GPa and generate enough heat (Temperatures reach 2760-3427 C) to transform a carbon material into a diamond.
101
It is a material produced by heating a mixture of clay and limestone or other similar materials. Specifically, its manufacture is a controlled chemical combination of
substances such as calcium, silicon, aluminum, iron, and others.
Portland cement
102
4 Stages in manufacturing portland cement.
(1) Raw materials are crushed and ground
(2) Components are blended to the right proportions
(3) Production of cement clinker in a kiln
(4) Crushing of clinker and addition of gypsum
103
Explain wet and dry process in the production of portland cement.
(1) Wet Process
- Large chunks of limestone are crushed into smaller pieces. These are then washed together with clay or shale in a tube or ball mill to form a slurry with about 35-45% water content. To get the blending right, the slurry is stored in slurry tanks to homogenize and perform composition adjustments.
(2) Dry Process
- a pre-homogenized mix of raw materials is first prepared and sent for crushing and grinding. The resulting raw meal is stored in silos for homogenization and further composition adjustments. This is achieved through agitation via compressed air.
104
During the burning process, various reactions occur to form 4 clinker compounds. What are these compounds?
1. tricalcium silicate
2. dicalcium silicate
3. tricalcium aluminate
4. tetra-calcium aluminoferrite
105
Explain how clinker is formed.
The formation of clinker compounds inside the kiln proceeds with evaporation of water, the evolution of carbon dioxide, and the fusion of lime and clay.
106
It is defined in portland cement context as the reaction of a non-hydrated cement or one of its constituents with water, associated with both chemical and physicomechanical changes in the system, in particular with setting and hardening.
Hydration
107
It is an inorganic material that hardens in the presence of water when mixed with calcium hydroxide. Historically, naturally occurring materials such as volcanic ash was used by the Romans to build their infrastructure.
Pozollan cement
108
It is manufactured from limestone and bauxite. This cement was used for marine applications due to its resistance to chemical attack, rapid hardening, and strength. Another attractive property of this cement is its high refractive index.
High alumina cement or or calcium aluminate cement
109
It is produced by mixing powdered magnesium oxide with a concentrated solution of magnesium chloride. For a given porosity, this cement exceeds the mechanical strengths of ordinary Portland cement.
Magnesium oxychloride or Sorel cement
110
It is a type of concrete that utilizes polymers as binding agents instead of cement.
Polymer concrete
111
5 Types of Lime
(1) Hydraulic limes
- obtained from burning limestone containing clay, and the nature of the product after mixing with water varies from putty to set cement.
(2) High-calcium-content limes
- harden only with the absorption of CO2 from the air, which
is a slow process.
(3) Magnesian limes or dolimes
- from limestones containing magnesium or where
dolomitic stone is calcined.
(4) Hydrated lime
- produced by treating quicklime with water in a process called “slaking”
(5) Quicklime
- the most common lime product, but it is almost always slaked before use.
112
Chemical equation representing the process of slaking to produce calcium hydroxide.
CaO (s) + H2O (l) → Ca(OH)2 (aq) + Heat
113
Give the chemical reaction equations involved in lime manufacture using high calcium lime and dolomitic lime.
For high calcium lime,
CaCO3 (s) + Heat ⇌ CaO (s) + CO2 (g)
For dolomitic lime,
CaCO3 ∙ MgCO3 (s) + Heat ⇌ MgO(s) + CaO (s) + 2CO2 (g)
114
Chemcial formula of gypsum.
(CaSO4 ⋅ 2H2O)
115
Explain how calcination of gypsum works.
(1) crushing and grinding the crystal
(2) heating to around 120 to 150 °C with constant stirring and agitation. First-settle plaster, or calcined gypsum, may be collected and sold at this point.
(3) raising the temperature further to 190 °C to completely eliminate water, producing second-settle plaster, or anhydrite.
116
5 miscellaneous calcium compounds
1. Calcium carbonate
- is one of the most abundant materials found in the earth’s
crust and it is a prominent industrial chemical that has uses in a wide variety of fields.
2. Calcium sulfide
- produced by reducing calcium sulfate (CaSO4) with coke
3. Halide salts
- binary chemical compounds containing a halogen atom and a cation.
4. Calcium arsenate
- produced by the reaction of calcium chloride, calcium hydroxide, and sodium arsenate or lime and arsenic acid
5. Calcium organic compounds
- Calcium acetate (Ca(C2H3O2)2) and calcium lactate (CaC6H10O6)
117
The production of magnesium compounds by separation from aqueous solutions may be divided into four processes:
1. Manufacture from seawater without evaporation, using seawater and lime as the principal raw materials.
2. Manufacture from bitterns or mother liquors from the solar evaporation of seawater of salt.
3. Manufacture from dolomite and seawater.
4. Manufacture from deep-well brines.
118
What is milk of magnesia?
magnesium hydroxide (Mg(OH)2)
119
4 Oxides and Hydroxide of Magnesium
1. Magnesium carbonates
- the primary use of magnesium carbonate is the production of magnesium oxide by calcining.
2. Magnesium sulfate
- Magnesium sulfate (MgSO4) is prepared by mixing sulfuric acid on magnesium carbonate .
3. Magnesium chloride
- Magnesium chloride (MgCl2) is made from hydrochloric acid and magnesium hydroxide.
4. Magnesium silicates
Magnesium silicates includes two widely used naturally occurring compounds, asbestos, and talc. Asbestos is a naturally occurring fibrous silicate material, with varying quantities of calcium and iron. Talc or talcum (3MgO ∙ 4SiO2 ∙ H2O) is a pure magnesium
silicate.
120
Modified True or False: The element's most commonly found in the earth's crust are oxygen, silicon, aluminum, and gold.
False, gold replace it with iron
121
3 main raw materials of ceramics
1. Clay
2. Feldspar
3. Sand
122
Describe beneficiation process used in ceramic industries.
It is a process of removing most of the impurities from a clay material.
123
Define firing process in ceramic industries.
A process of bringing clay and glazes up to a high temperature until it become "mature"—that is they have reached their of optimal level of melting.
124
In firing process utilized by ceramic industries, there are 4 reactions may happen which serve as the bases for chemical conversions. What are those?
1. Dehydration (150-650 deg C)
2. Calcination (600-900 deg C)
3. Oxidation of ferrous iron and organic matter (350-900 deg C)
4. Silicate formation (900 deg C and higher)
125
This is a process by which ceramic bodies undergo a certain glass formation during heating, which depends on the relative amounts of refractory and fluxing oxides in the composition, temperature, and time of heating.
Vitrification
126
Difference between wet-process, dry process and cast in manufacturing porcelain.
They only vary with the drying and forming process.
Wet process- the body of the porcelain is formed either by soft plastic forming or stiff plastic forming.
Dry process- subjected to pressing
Cast- through slip-casting
127
Six main phases in manufacturing bricks
1. Mining and Storage
2. Raw material preparation
3. Brick Formation
4. Drying
5. Firing
6. De-hacking
128
4 main subdivisions of refractory ceramics.
1. Fire-clay (alumina-silica mixtures)
2. Silica
3. Basic (rich in magnesia, MgO)
4. Special
129
Define porosity and give its formula.
Porosity is the percentage of void space in a rock.
Formula: n = V(pore space)/V(total)
130
True or False: The least porous a brick, the greatest its strength, thermal conductivity, and heat capacity.
TRUE
131
It is used to describe the flaking off or fracturing of a refractory brick in ceramic industries due to uneven heat stress/compression distribution or simply when firing temperatures are not high enough .
Spalling
132
Define thermal conductivity and give its formula.
Thermal conductivity is the ability of a material to transfer heat.
Formula: q = -k(dT/dx)
133
What are the 5 main processes in manufacturing salt or sodium chloride?
1. Evaporation
2. Precipitation
3. Crystallization
4. Harvesting
5. Washing and Drying
134
2 Common Techniques used by most of the salt companies in manufacturing salt.
1. Solar salt production
2. Vacuum pan system
135
2 equations for the production of salt cake from sulfuric acid and salt.
NaCl + H2SO4 -> NaHSO4 + HCl
NaHSO4 + NaCl -> Na2SO4 + HCl
136
Chemical Reaction for manufacturing NaHSO4 or the sodium bisulfate
NaCl + H2SO4 -> HCl + NaHSO4
137
Chemical Reaction for manufacturing Na2SO3 or the sodium sulfite
Na2CO3 + SO2 -> Na2SO3 + CO2
138
Chemical Reactions for manufacturing Na2S or the sodium sulfide
Na2SO4 + 4C -> Na2S + 4C
Na2SO4 + 4CO -> Na2S + 4CO2
139
Chemical Reaction for manufacturing Na2O2 or the sodium peroxide
4Na + O2 -> 2Na2O
2Na2O + O2 -> 2Na2O2
140
Define electrolytic process.
It is used to remove components from a solution or purify commodities like metals.
141
3 essential ingredients of electrolytic process.
1. electricity
2. a material that contains free ions
3. two items that may serve as electrodes.
142
Explain how aluminum is manufactured in electrolytic industries.
Metallic aluminum is created via the electrolytic reduction of pure alumina in a bath of fused cryolite.
143
Give the two manufacturing processes of magnesium in electrolytic industries.
1. Electrolysis of Magnesium Chloride
- Magnesium chloride is obtained from salines, brine wells, and when magnesium hydroxide (from seawater or dolomite) reacts with hydrochloric acid. This solution is then evaporated to solid form in direct-fired evaporators and dried on a shelf. The magnesium chloride is delivered to the electrolytic cells for decomposition into magnesium metal and chlorine gas.
2. Silicothermic, or Ferrosilicon Process
- The procedure involves combining dead-burned, powdered dolomite with 70 to 80 percent ferrosilicon, 1 percent fluorspar, and pelletizing the mixture. The pellets are charged into the furnace subject to high temperature (1170°C) and vacuum. The liberated magnesium is then collected on the condenser lining at the condenser.
144
Explain how sodium is manufactured in electrolytic industries.
Sodium and calcium combine at the cathode, but when the
temperature drops, the solubility of calcium decreases resulting in heavier calcium crystals settle back into the bath. After being filtered, the crude sodium has a 99.9% purity.
145
It is an inorganic compound which can be described as a white crystalline substance that is water-soluble. It is noncombustible by itself, but it may combine with combustible substances to create a highly flammable combination that, if the combustible substance is separated
finely, it might be explosive.
Chlorate
146
Explain how chlorates are produced in electrolytic industries.
The production of sodium chlorate is performed by the electrolysis of saturated brine mixed with sodium dichromate. Electrolysis yields sodium hydroxide at the cathode and chlorine at the anode. Yet, because the cell lacks a diaphragm, mixing occurs and sodium hypochlorite is produced. The liquor is heated in tanks where it is pumped in order to remove any remaining hypochlorite. As sodium chloride evaporates, the sodium chlorate crystals are then
dried and spun in a centrifuge to obtain sodium chlorate.
147
Explain how perchlorates are manufactured in electrolytic industries.
Potassium perchlorate is created in order to transform sodium chlorate into sodium perchlorate in a steel electrolytic cell with platinum anodes. Afterwards, crystals of potassium perchlorate are precipitated by adding a potassium chloride solution to sodium perchlorate. The electrolysis of solutions of potassium chloride can also yield perchlorates.
148
Differentiate primary cells and secondary cells in electrolytic industries.
In primary cells, electricity is produced through a chemical reaction that is not easily reversible; hence, chemicals must be replenished after the reaction has occurred.
Secondary cells rely on chemical processes that may be stopped by electrical energy, therefore replacement of chemical components is not necessary.
149
Explain how lead storage battery generates electricity in electrolytic industries.
The reaction take place between two electrodes dipping into partly diluted sulfuric acid. The battery consists of lead peroxide at the positive plate and sponge lead at the
negative plate which are insulated from each other by a separator made of microporous material. Filled with diluted sulfuric acid, electrical energy is generated when reactions take place.
150
Physically as rigid, undercooled liquid without definite melting point, with sufficiently high viscosity; chemically as the fusion of volatile inorganic oxides.
Glass
151
Major ingredients/components in glassmaking.
1. Silica - making up the largest percentage
2. Lime - a stabilizer making the glass strong and water resistant
3. Soda - a flux lowering the melting point
152
Six Basic Categories of Glasses
1. Vitreous silica - fusing pure silica without a flux.
2. Alkali silicates - “water glass”, made of only soda ash and sand melted together.
3. Lime glass - most common
4. Lead glass- high refractive index and high dispersion
5. Borosilicates - 10% to 13% boron trioxide and 80%-83% silica
6. Special Glasses
153
Methods of glass manufacturing
1. Raw materials preparation
2. Melting
3. Shaping
4. Annealing
5. Finishing
154
A type of heat exchanger used by glass industries in which heat is transferred from the flue gases to the combustion air in co-current or in countercurrent flow.
Recuperator
155
Iron rods used in the glass industry to hold and shape softened glass. These were also used to take the shaped glass out of that globe and place it.
Punty or pontil
156
This process involves heating the glass to a specific temperature, holding it at that temperature for a period of time, and then gradually cooling it down.
Annealing
157
Give 1-2 glass manufacturers here in Philippines
Asahi Glass Company
San Miguel Yamamura Corp.
Asia Brewery Incorporated
Anglo Watsons Class
Arcya Glass
158
True or False:
The vapor pressure of the refrigerant at the evaporator temperature should be greater than atmospheric pressure to avoid air leaking.
True
159
Modified True or False: The condenser absorbs heat into the system.
False, Evaporator
160
Modified True or False: Energy systems without waste or resource consumption is an open system.
False, Closed System
161
3 Primary Energy Sources
1. Conventional Energy Sources (CES)
2. Nuclear Power
3. New and Renewable Energy Sources (NRES)
162
5 Renewable Sources
1. Solar Power
2. Hydropower
3. Geothermal
4. Wind
5. Biomass
163
3 Non-Renewable Sources
1. Fuels (Solid, Liquid, Gas)
2. Fuel Cells
3. Nuclear Power
164
What’s the common thing between all the energy sources in context of power production?
The common thing about all the energy sources is that they need to either convert other types of energy into or produce mechanical energy, which spins the turbine that’s connected to the generator, which converts the mechanical energy into electrical energy.
165
Define Refrigeration Process
It is a process of removing heat from a place where it is not wanted and transferring that heat to a place where it makes little or no difference.
166
How does refrigeration process work?
1. The evaporator absorbs heat into the system.
2. The compressor pumps the heat-laden vapor.
3. The condenser rejects heat from the system.
4. The expansion device meters the flow of refrigerant.
167
Define Cogeneration
It is a system that produces heat and electricity simultaneously in a single plant.
168
Working fluid used in the refrigeration cycle of air conditioning systems and heat pumps.
Refrigerant
169
Chlor-alkali Process Reaction
2NaCl(aq) + 2H2O(l) → 2NaOH(aq) + Cl2(g) + H2(g)
170
3 Major Products of chlor alkali industry
1. Soda Ash (Na2CO3)
- also known as sodium carbonate, is a lightweight solid that is easily soluble in water. It is an alkali chemical which is mostly produced from sodium chloride and limestone.
2. Caustic Soda (NaOH)
- chemical compound made of sodium hydroxide. It is an alkali, which means it can neutralize acids and is soluble in water.
3. Chlorine (Cl2)
- used in the synthesis of organic chemicals
171
What are the 3 different methods used in chlor-alkali. Among the 3, which is better?
1. mercury cell
2. diaphragm cell
3. membrane cell
- Membrane cell is better because it involves with ion exchange only, unlike diaphragm cell which uses asbestos and mercury cell which uses mercury metal that poses danger to health.
172
Explain how le blanc process is used in manufacturing soda ash.
1. Production of Salt Cake
- Common salt (NaCl) was first reacted with sulfuric acid (H2SO4) to produce sodium sulfate (Na2SO4) and hydrochloric acid (HCl). The sodium sulfate was then heated with limestone (CaCO3) and coal to produce salt cake (Na2SO4) and carbon dioxide .
2. Conversion of Salt Cake to Soda Ash
- The salt cake was then reacted with limestone (CaCO3) and coal in a process known as black ash fusion. This produced a mixture of soda ash (Na2CO3), calcium sulfide (CaS), and coal ash (unburned coal).
3. Recovery of Soda Ash
- The mixture of soda ash, calcium sulfide, and coal ash was
then dissolved in water and the insoluble calcium sulfide was removed by filtration. The resulting solution of soda ash was then concentrated and crystallized to produce a pure product.
173
Difference between electric furnaces and combustion furnaces.
Electric furnaces- generate heat through electricity
Combustion furnaces- use fuels such as liquid, solid and gaseous fuels as heating surface
174
Differentiate the types of electric furnaces.
1. Arc furnaces
- the heat in the arc furnace is generated by an electric arc between two or more electrodes, that are usually graphite or carbon, or between the electrodes and the furnace charge.
2. Induction furnaces
- heat is generated by electromagnetic induction of copper coil that surrounds the chamber.
3. Resistance furnace
- process of generating heat by running an electric current through a conductor's resistance.
175
The equation for manufacturing silicon carbide in electrochemical industries.
SiO2 + 3C -> SiC + 2CO
176
The chemical reaction for the production of boron carbide in electrochemical industries.
2B2O3 + 7C -> B4C + 6CO
177
An alloy of carbon and iron.
Steel
178
Modified True or False:
Steel becomes brittle if its carbon content is decreased beyond 1.5%.
False, increased beyond
179
An intermediate good used by the iron industry in the production of steel, which is developed by smelting iron ore in a blast furnace.
Pig Iron
180
What are the 2 miscellaneous electrothermal products?
1. Calcium Carbide
2. Fused Silica
181
Explain how soda ash is manufactured by solvay process.
1. Brine Purification
- Remove impurities in brine solution (saltwater) such as calcium, magnesium, and other metal ions that can interfere with the chemical reactions in the process. The brine solution is treated with lime and carbon dioxide to precipitate these impurities.
2. Sodium Hydrogen Carbonate (NaHCO3) Production
- ammonia is added to the purified brine solution, followed by carbon dioxide to produce sodium hydrogen carbonate and ammonium chloride.
3. Sodium Carbonate (Na2CO3) Formation
- The sodium hydrogen carbonate (NaHCO3) is then heated to produce sodium carbonate and water vapor.
4. Sodium Carbonate Crystallization
- The sodium carbonate is then crystallized from the solution and dried to remove any remaining moisture. The resulting product is soda ash (anhydrous sodium carbonate).
182
Chemical formula of Epsom salts
MgSO4∙ 7H2O
183
Explain how lime-soda process works in manufacturing chlorine and caustic coda .
1. Preparation of Salt Brine
- A solution of sodium chloride (salt) is prepared and purified to remove any impurities.
2. Purification of Limestone
- Limestone is first crushed and then purified to remove any
impurities.
3. Reaction with Calcium Hydroxide
- The purified limestone is then reacted with calcium hydroxide (lime) to produce calcium carbonate (limestone) and calcium chloride.
4. Carbonation of Calcium Hydroxide
- Carbon dioxide is then bubbled through the calcium hydroxide solution to produce calcium carbonate and water.
5. Reaction with Salt Brine
- The calcium chloride produced in step 3 is then reacted with
the salt brine to produce sodium chloride (salt) and calcium hydroxide.
6. Hydrolysis of Calcium Hydroxide
- The calcium hydroxide produced in step 5 is then hydrolyzed to produce calcium oxide (lime) and water.
7. Reaction with Salt Brine
- The calcium oxide is then reacted with the salt brine to produce sodium hydroxide (caustic soda) and calcium chloride.
184
Explain how chlor-alkali process works in manufacturing chlorine and caustic coda .
1. Preparation of Brine Solution
- Preparing a brine solution by dissolving common salt (sodium chloride) in water.
2. Purification of Brine Solution
- The brine solution is then purified to remove any impurities, such as calcium and magnesium ions, which can affect the efficiency of the electrolysis process.
3. Electrolysis of Brine Solution
- The purified brine solution is then fed into an electrolytic cell. When an electric current is passed through the cell, the salt in the brine solution is dissociated into sodium and chlorine ions.
4. Production of Chlorine Gas
- At the anode, chlorine gas is produced by the oxidation
of chloride ions.
5. Production of Sodium Hydroxide Solution
- At the cathode, sodium ions react with water to form sodium hydroxide solution (caustic soda) and hydrogen gas.
185
This involves the removal of pollutants such as calcium, iron, and magnesium which clog up membranes and diaphragms in cells.
Brine Purification
186
This process is an essential part of the chlor-alkali industry, it involves using an electric current to perform a large-scale
process to produce of chlorine gas, hydrogen gas, and sodium hydroxide.
Brine Electrolysis
187
This is a process that is used in the chlor-alkali industry to recover salt as a byproduct from the electrolysis process. The salt is typically recovered from the brine then is used as a feedstock for the next electrolysis process.
Salt separation
188
It is an important process in the chlor-alkali industry as it purifies and concentrates the brine prior to electrolysis, and
recovers valuable byproducts including sodium chloride and sodium sulfate.
Evaporation
189
True or False:
Le blanc process is much more efficient than solvay process in manufacturing soda ash.
False
190
True or False:
Lime-Soda is much more efficient than chlor-alkali process in manufacturing caustic soda and chlorine.
False
