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Sulfuric Acid Essay Research Paper Sulfuric Acid

Sulfuric Acid Essay, Research Paper

Sulfuric Acid Industry in Ontario

Among the many plants in Ontario where sulfuric acid is

produced, there are three major plant locations that should

be noted on account of their greater size. These are: (1)

Inco. – Sudbury, (2) Noranda Mines Ltd. – Welland, and (3) Sulfide – Ontario

There are a number of factors which govern the location

of each manufacturing plant. Some of these factors that have

to be considered when deciding the location of a Sulfuric Acid plant are:

a. Whether there is ready access to raw materials;

b. Whether the location is close to major transportation routes;

c. Whether there is a suitable work force in the area for

plant construction and operation;

d. Whether there is sufficient energy resources readily available;

e. Whether or not the chemical plant can carry out its

operation without any unacceptable damage to the environment.

Listed above are the basic deciding factors that govern

the location of a plant. The following will explain in

greater detail why these factors should be considered.1) Raw Materials

The plant needs to be close to the raw materials that

are involved in the production of sulfuric acid such as

sulfur, lead, copper, zinc sulfides, etc..2) Transportation

A manufacturer must consider proximity to transpor-

tation routes and the location of both the source of raw

materials and the market for the product. The raw

materials have to be transported to the plant, and the

final product must be transported to the customer or

distributor. Economic pros and cons must also be thought

about. For example, must sulfuric plants are located

near the market because it costs more to transport

sulfuric acid than the main raw materials, sulfur.

Elaborate commission proof container are required for the

transportation of sulfuric acid while sulfur can be much

more easily transported by truck or railway car.

3) Human Resources For a sulfuric acid plant to operate, a

large work force will obviously be required. The plant must

employ chemists, technicians, administrators, computer

operators, and people in sales and marketing. A large number

of workers will also be required for the daily operation of

the plant. A work force of this diversity is therefore likely

to be found only near major centres of population.4) Energy Demands

Large amounts of energy will also be required for the

production of many industrial chemicals. Thus, proximity

to a plentiful supply of energy is often a determining

factor in deciding the plant’s location. 5) Environmental Concerns

Most importantly, however, concerns about the

environment must be carefully taken into consideration.

The chemical reaction of changing sulfur and other

substances to sulfuric acid results in the formation of

other substances like sulfur dioxide. This causes acid

rain. Therefore, there is a big problem about sulfuric

plants causing damage to our environment as the plant is

a source of sulfur emission leading to that of acid rain.6) Water Supplies

Still another factor is the closeness of the location

of the plants to water supplies as many manufacturing

plants use water for cooling purposes.

In addition to these factors, these questions must also

be answered: Is land available near the proposed site at a

reasonable cost? Is the climate of the area suitable? Are

the general living conditions in the area suitable for the

people involved who will be relocating in the area? Is there

any suggestions offered by governments to locate in a particular region?

The final decision on where the sulfuric acid plant

really involves a careful examination and a compromise among

all of the factors that have been discussed above.Producing Sulfuric Acid

Sulfuric acid is produced by two principal processes–

the chamber process and the contact process.

The contact process is the current process being used to

produce sulfuric acid. In the contact process, a purified

dry gas mixture containing 7-10% sulfur dioxide and 11-14%

oxygen is passed through a preheater to a steel reactor

containing a platinum or vanadium peroxide catalyst. The

catalyst promotes the oxidation of sulfur dioxide to

trioxide. This then reacts with water to produce sulfuric

acid. In practice, sulfur trioxide reacts not with pure

water but with recycled sulfuric acid.The reactions are: 2SO2 + O2 –* 2SO3

SO3 + H2O –* H2SO4 The product of the contact plants is 98-100% acid. This

can either be diluted to lower concentrations or made

stronger with sulfur trioxide to yield oleums. For the

process, the sources of sulfur dioxide may be produced from

pure sulfur, from pyrite, recovered from smelter operations

or by oxidation of hydrogen sulfide recovered from the

purification of water gas, refinery gas, natural gas and other fuels.

Battery Acid Industry Many industries depend on sulfuric acid. Among these

industries is the battery acid industry.

The electric battery or cell produces power by means of

a chemical reaction. A battery can be primary or secondary.

All batteries, primary or secondary, work as a result of a

chemical reaction. This reaction produces an electric

current because the atoms of which chemical elements are

made, are held together by electrical forces when they react to form compounds.

A battery cell consists of three basic parts; a

positively charged electrode, called the cathode, a

negatively charged electrode, called the anode, and a

chemical substance, called an electrolyte, in which the

electrodes are immersed. In either a wet or dry cell,

sufficient liquid must be present to allow the chemical reactions to take place.

Electricity is generated in cells because when any of

these chemical substances is dissolved in water , its

molecules break up and become electrically charged ions.

Sulfuric acid is a good example. Sulfuric acid, H2SO4, has

molecules of which consist of two atoms of hydrogen, one of

sulfur and four oxygen. When dissolved in water, the

molecules split into three parts, the two atoms of hydrogen

separate and in the process each loses an electron, becoming

a positively charged ion (H+). The sulfur atom and the four

atoms of oxygen remain together as a sulfate group (SO4), and

acquire the two electrons lost by the hydrogen atoms, thus

becoming negatively charged (SO4–). These groups can

combine with others of opposite charge to form other compounds.

The lead-acid cell uses sulfuric acid as the

electrolyte. The lead-acid storage battery is the most

common secondary battery used today, and is typical of those

used in automobiles. The following will describe both the

charging and discharging phase of the lead-storage battery

and how sulfuric acid, as the electrolyte, is used in the

process. The lead storage battery consists of two electrodes

or plates, which are made of lead and lead peroxide and are

immersed in an electrolytic solution of sulfuric acid. The

lead is the anode and the lead peroxide is the cathode. When

the battery is used, both electrodes are converted to lead

sulfate by the following process. At the sulfate ion that is

present in the solution from the sulfuric acid. At the

cathode, meanwhile, the lead peroxide accepts two electrons

and releases the oxygen; lead oxide is formed first, and then

lead joins the sulfate ion to form lead sulfate. At the same

time, four hydrogen ions released from the acid join the

oxygen released from the lead peroxide to form water. When

all the sulfuric acid is used up, the battery is “discharged”

produces no current. The battery can be recharged by passing

the current through it in the opposite direction. This

process reverses all the previous reactions and forms lead at

the anode and lead peroxide at the cathode.Proposed Problem

i) The concentration of sulfuric acid is 0.0443 mol/L.

The pH is: No. mol of hydrogen ions = 0.0443 mol/L x 2

= 0.0886 mol/L hydrogen ions pH = – log [H]

= – log (0.0886) = – (-1.0525) = 1.05 Therefore, pH is 1.05.

ii) The amount of base needed to neutralize the lake water is:

volume of lake = 2000m x 800m x 50m

= 800,000,000 m3 or 8Ч108 m3

since 1m3=1000L, therefore 8Ч1011 L

0.0443 mol/L x 8Ч1011 = 3.54 x 1010 mol of H2SO4 in water

# mol NaOH = 3.54 x 1010 mol H2SO4 x 2 mol NaOH

1 mol H2SO4

= 7.08 x 1010 mol of NaOH needed

Mass of NaOH = 7.08 x 1010 mol NaOH x 40 g NaOH

1 mol NaOH

= 2.83 x 1012 g NaOH or 2.83 x 109 kg NaOH

Therefore a total of 2.83 x 1012 g of NaOH is needed to

neutralize the lake water.iii) The use of sodium hydroxide versus limestone to

neutralize the lake water:

Sodium hydroxide: Sodium hydroxide produces water when

reacting with an acid, it also dissolves in water quite

readily. When using sodium hydroxide to neutralize a lake,

there may be several problems. One problem is that when

sodium hydroxide dissolves in water, it gives off heat and

this may harm aquatic living organisms. Besides this, vast

amounts of sodium hydroxide is required to neutralize a lake

therefore large amounts of this substance which is corrosive

will have to be transported. This is a great risk to the

environment if a spill was to occur.

The following equation shows that water is produced when

using sodium hydroxide.2NaOH + H2SO4 –* Na2 SO4 + 2H2O

Limestone: Another way to neutralize a lake is by

liming. Liming of lakes must be done with considerable

caution and with an awareness that the aquatic ecosystem

will not be restored to its original pre-acidic state even

though the pH of water may have returned to more normal

levels. When limestone dissolves in water it produces carbon

dioxide. This could be a problem since a higher content of

carbon dioxide would mean a lowered oxygen content especially

when much algae growth is present. As a result, fish and

other organisms may suffer. Limestone also does not dissolve

as readily as sodium hydroxide thus taking a longer period of

time to react with sulfuric acid to neutralize the lake. The

equation for the neutralization using limestone is as follows:

Ca CO3 + H2SO4 –* CaSO4 + H2O.

iv) The effect of the Acid or excessive Base on the plant and animal life:

You will probably find that there aren’t many aquatic

living organisms in waters that are excessively basic or

acidic. A high acidic or basic content in lakes kill fishes

and other aquatic species. Prolonged exposure to acidic or

excessively basic conditions can lead to reproductive failure

and morphological aberration of fish. A lowered pH tends to

neutralize toxic metals. The accumulation of such metals in

fish contaminates food chains of which we are a part as these

metals can make fish unfit for human consumption.

Acidification of a lake causes a reduction of the production

of phytoplankton (which is a primary producer) as well as in

the productivity of the growth of many other aquatic plants.

In acidic conditions, zooplankton species will probably

becompletely eliminated. In addition, bacterial

decomposition of dead matter is seriously retarded in

acidified lake waters. Other effects of acidic conditions

arean overfertilization of algae and other microscopic plant

lifecausing algae blooms. Overgrowth of these consumes

quickly most of the oxygen in water thus causing other life

forms to die from oxygen starvation.

When there are excessive base or acid in waters, not

only do aquatic organisms get affected but animals who depend

on aquatic plants to survive will starve too, since few

aquatic plants survive in such conditions. Therefore each

organism in the aquatic ecosystem is effected by excessive

basic or acidic conditions because anything affecting one

organism will affect the food chain, sending repercussions

throughout the entire ecosystem.

v) The factors that govern this plant’s location, if this

plant employs 40% of the towns people:

The major factors that would govern this plant’s

location would be whether there is ready access to raw

materials; whether the location is close to major

transportation routes; whether energy resources are readily

available and if there is an adequate water supply in the

area. Since this plant would employ 40% of the towns people,

the plant should be close to the town while still far enough

so that in case of any leakage of the plant, the town will be

within a safe distance of being severely affected. The

factor of whether the general living conditions in the area

are suitable for the workers should also be considered as well.




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