This document provides information about an assignment submitted by Nimra Nisa for her Inorganic Chemistry course. The assignment topic is the application of zeolites. The document defines zeolites and discusses their chemical composition and properties. It describes natural and synthetic zeolites and their various applications, such as in radioactive waste treatment, water treatment, adsorption, catalysis, agriculture, and medicine. Synthetic zeolites applications include uses as desiccants, ion exchangers, in households, and for hydrocarbon sieving. The document provides examples and details for many of the applications discussed.

1. ASSIGNMENT NO 1
TOPIC:
APPLICATION OF ZEOLITES
SUBJECT:
INORGANIC CHEMISTRY ||
COURSE CODE:
CHEM-402
SUBMITTED TO:
MADAM IQRA
SUBMITTED BY:
NIMRA NISA
ROLL NUMBER:
0053-BS-CHEM-2019
SESSION:
2019-2023
SEMESTER:
7th
SUBMITTED DATE: 12-12-2022

2. Table of content
Zeolites………………………………………………………………………….2
Definition……………………………………………………………………..2
Chemical composition…………………………………………...…………....2
Properties of zeolites …………………………………………………………3
Types of zeolites………………………………………………………………..3
Natural zeolites………………………………………………………………3
Synthetic zeolites…………………………………………………………….3
Applications of Natural zeolites……………………………………………….3
Radioactive waste treatment …………………………………………………4
Waste water treatment/ cation exchanger ……………………………………4
Adsorption …………………………………………………………………...4
Dehydration and rehydration ……….………………………………………..5
Biological activities ………………………………………………………….5
Surface modification ………………………………………………………...5
As a solar energy storage…………………………………………………….5
As a building material ……………………………………………………….5
Applications of Synthetic zeolites…………………………………………….6
Desiccation ………………………………………………………………….6
Ion exchanger………………………………………………………………...6
Agriculture…………………………………………………………………...6
Catalytic property …………………………………………………………...7
Household …………………………………………………………………...7
Molecular and hydrocarbon sieving …………………………………………7
In medicine …………………………………………………………………..8
In environmental decontamination …………………………………………..8
References ……………………………………………………………………...9

3. Zeolite
Definition
Zeolite are frequently referred to as the molecular sieves of hydrated crystalline
aluminosilicates minerals are made from interlinked tetrahedral of alumina and silica and
belonging to the group of tectosilicates. The name of these aluminosilicates is called zeolites.
Permutit is another name for zeolites.
Zeolites are the porous materials with microporous channels because they have tiny pores with
set sizes and large surface area that allow small molecules to pass through them with ease as
compared to large molecules. That’s why zeolites foam many different crystalline structures.
These channels are connected, organized and have dimension range between 0.2 to 2nm.
Zeolites are three-dimension framework is made of Al-O-Si, microporous solid, having
different crystalline structure which built up of different elements include aluminum, silicon,
oxygen, hydrogen with alkali or alkaline earth metals and gap between these elements trapped
by some water molecules.
Chemical composition
The general composition of zeolites is:
Mn
x/n Si1-xAlxO2. yH2O or Mb/a [(AlO2)b (SiO2)c]. yH2O
Where, M is the alkali or alkaline earth metals like Na, K, Ca etc
Si1-xAlxO2 is the silicates and aluminum oxides so this mean that Si/Al ratio is greater than 1
and x is the lesser than 0.5. It is not hard and fast rule that zeolites contain always high
concentration of aluminum because most of zeolites are synthesized in which contain high
concentration of silicates.
Table 1.1 Chemical composition of zeolite and structure
Properties of zeolites
➢ The melting point of zeolites is very high 1000℃ due to its extremely stable solid structure
that can stand under different environmental conditions.
➢ They can withstand with high temperature and pressure, are inert to air oxidation and don’t
dissolve in polar or other non-polar solution.

4. ➢ The most important and unique property of zeolite is their open cage like framework that
helps the zeolites to trap other molecules inside it. This may include the water molecules,
alkali and alkaline earth metals.
➢ In some zeolites contain more alumina while some contain less alumina, so rich- alumina
zeolites attract the polar molecules like water while less- alumina zeolites contain more
silica attract the non-polar molecules.
➢ Some other unique properties of zeolites are high surface area, uniform microporous size,
high hydro thermal stability, environment harmless, shape selectivity, non-corrosive.
Types of zeolites
➢ Natural zeolites
These zeolites have also existed in nature in the foam of minerals but mostly found in rocks
and sedimentary rocks. So, they mainly possessed by natural ores bodies in which silica to
alumina ratio range is 5 to 1. These zeolites are non-porous because the cavity filled by some
molecules of water, alkali or alkaline earth metals.
➢ Synthesis zeolites
These zeolites are mostly synthesized in the laboratories by modifying the naturally occurring
zeolites or new foam of zeolites. They are mainly prepared by heating together China clay.
Feldspar and soda ash. These zeolites are porous and posses get structure. They are high
exchange capacity due to high charge and weight as compared to natural zeolites.
Table 1.2: Examples of natural and synthetic zeolites
Application of Zeolites
Natural zeolites
➢ Radioactive waste treatment
Natural zeolites such as clinoptilolite, chabazite have been study for removal of radionuclides
Cs (137), Co (60), Sr (90) form liquid radioactive waste. It absorbs radioisotopes such as Sr
and Cs. It is used to clean up Sr/Cs in Chernobyl disaster at Soret Union on 28th
April 1986 and
their Mila Island at Pennsylvania on 28th
March 1979.

5. It is also used to decontaminate Cs 137 at Fukushima, Japan on 11 March 2011 due to
earthquake.
➢ Waste water treatment/ cation exchange
Dur to good adsorption capacity, clinoptilolite was used to remove ammonia and hydrogen
sulphide from waste water. Therefore, it is used as tertiary waste water treatment system.
Zeolites are the materials that can swap out naturally occurring cations for other cations based
on ion selectivity. This technology has been used by large industrial companies like IBM to
cleanse wastewater that contains heavy metals. Natural zeolites reduced the quantity of
ammonium in wastewater and sewage to non-toxic, acceptable levels.
➢ Adsorption
Adsorption in zeolites is significantly different from that in like silica gel or active coal, which
have a broad size distribution of pore sizes. In zeolite the pores are arranged in a regular fashion
with only one discrete pore size and also molecular dimensions.
The adsorption process is fully reversible and of purely physical nature. The structure of the
zeolite is unchanged during the adsorption process and its later regeneration. The adsorption
on molecular sieves is therefore dependent on the following physical molecular properties:
• The first is the size and shape of molecules or ions larger than the pore opening of the
zeolite can’t be adsorbed, smaller molecules or ions can.
• The second one is the molecular polarity due the charge on outer and inner zeolitic
surface particle, molecules with large polarity or polarizability can be adsorbed
preferentially under identical conditions.
Example: adsorption process on zeolite is used to remove polar H2O, H2S, and CO2 from
natural gas and developed a zeolite-adsorption process for purifying methane produced in a
landfill.
➢ Dehydration and rehydration
Natural zeolites may hold water up to 60% of their weight due to a high porosity of the
crystalline structure. Water molecules in the pores could be easily evaporated or reabsorbed
without damage to such structures.
Zeolites assure a permanent water reservoir, providing prolonged moisture during dry periods;
they also promote a rapid rewetting and improve the lateral spread of water into the root zone
during irrigation. This results in a saving in the quantity of water needed for irrigation.
➢ Biological activities
Natural zeolite has been used successfully in medical therapy and has been shown to exhibit a
variety of biological activities. It helps prevent plant burning, which can be brought on by using
too much fertilizer, by trapping and gradually releasing valuable nutrients. It also improves
feed conversion in concentrated animal growing facilities. It can also reduce airborne ammonia
by up to 80%.
➢ Surface modification of natural zeolites
Surface-modified of natural zeolites remove toxic substances from animal food. Natural zeolite
can be further treated with additional amine to produce anion exchangers capable of taking up
chromate, arsenate, selenate, and other metal oxyanions from aqueous solutions. Clinoptilolite

6. can be surface-modified with long-chain quaternary amines to allow it to adsorb benzene,
toluene, and xylene.
➢ As a solar energy storage
Solar heat collected by solar thermal collectors has been thermochemically stored in zeolites.
Additionally, adsorption refrigeration uses it. Zeolites' high heat of adsorption and capacity to
hydrate and dehydrate while maintaining structural stability are heavily utilized in such
applications. Natural zeolites are excellent for capturing solar heat and waste heat energy
because of their inherent exothermic reaction during the transition from a dehydrated to a
hydrated state.
➢ As a building material
Numerous research has looked into the use of natural zeolite as an additional cementitious
material in the creation of cement, mortar, and concrete. In general, it has been demonstrated
that adding natural zeolite to cement and concrete composites improves their mechanical
strength and durability features. Of the four million tonnes of natural zeolites mined each year,
2.5 million tonnes are sent to China to be used in the production of lightweight concrete. In
areas where it is abundant, such as Republic Square in Yerevan, Armenia, with its stunning
architectural design, volcanic tuff may be cut with handsaws and utilized directly to create
homes and other types of buildings.

7. Synthetic zeolites
➢ Desiccation (dehydration and rehydration)
Zeolites can be used as desiccation drying agent, due to its high porosity they can hold water
and water present in the pores can be evaporated without damaging its structure.
Zeolite A is used as water softener in the detergent.
Hydrated zeolite A ⇋ anhydrous zeolite A + 27 H2O
Zeolite A is also used as drying agent for air, natural gas and organic solvent.
➢ Ion exchanger
The cations present in the cavities can be exchanged with other cations. When in aqueous
conditions, hydrated cations within the zeolite pores are easily exchangeable with other cations
because they are weakly attached to the zeolite framework.
Applications of this include the use of zeolites in detergents and soaps as well as water
softening equipment. Zeolites can be used as detergents. Zeolites are used extensively in
detergent formulations as water softening agents in place of phosphates. They achieve this by
trading the calcium and magnesium in the water for the sodium in the zeolite. Even radioactive
ions in tainted water can be eliminated.
Zeolites are extremely effective for the exchange of ions due to their cage-like structure. As an
illustration, hard water is run through a column of sodium-containing zeolites. Zeolites are used
in this technique to retain calcium and magnesium while releasing sodium ions, softening the
water and making it sodium-rich. Today, zeolites are also utilized in detergent to remove
calcium and magnesium, softening the water and enhancing the detergent's efficacy. Act as
cation exchangers. Cation exchanger capacity in the hard water can be exchanged by Na+ of
sodium.
Order of strength of adsorption of cations is
Al3+ > Ca2+ > Mg2+ > K+ > NH4
+ > Na+ > H+
Ion exchange zeolite helpful in hard water softening. Calcium and magnesium present in the
hard water can be exchanged by Na+ of sodium zeolites.
2NaZ + Ca2+ ⇋ CaZ2 + 2Na+
CaZ2 + 2NaCl ⇋ 2NaZ + CaCl2
➢ Agriculture
The synthetic zeolites control the release of fertilizers in agriculture lands. The loss of nitrogen
can be reduced by zeolites. Release of phosphorus from phosphatic fertilizers can be controlled
by adding ammonium zeolites to the phosphatic fertilizers such as apatite, calcium phosphate
etc. Zeolites from Cuba and Japan have a long history of application in agriculture in Eastern
Europe. When added to cattle rations, ammonia and odor emissions are reduced, feed
utilization is increased, mycotoxin absorption is aided, and trace elements may be added at a
rate of about 5%. NASA used nutrient-loaded zeolites as slow-release fertilizers a number of
years ago.
Zeolites are also used in crop production, environmental protection, waste water treatment,
resource conservation and soil structural benefits.

8. ➢ Catalytic property
Zeolite is a very powerful catalyst due to its porous structure. Zeolite is frequently referred to
as shape-selective catalysis because it selectively reacts with specific chemicals and has pores
that are set in size and shape.
• To compensate the charge (negative) on the zeolites, some hydrogen ions are also present,
resulting acidic property of zeolites and responsible for catalytic activity of zeolites.
• Catalytic cracking due to the various reactions like isomerization, dehydrogenation,
hydrogen transfer, cyclization, condensation, alkylation and dealkylation occur in the
channels of zeolites.
So, Zeolites are effective catalysts for a wide range of important organic molecule reactions. A
wide variety of catalytic reactions, such as acid-base and metal-induced reactions, can be
facilitated by zeolites. Zeolites can be employed as supports for active metals or reagents as
well as acid catalysts. Zeolites have the potential to be shape-selective catalysts through either
transition state selectivity or the exclusion of rival reactants based on molecular size. They have
also been employed as catalysts for oxidation. The zeolite's pores, where the reactions can take
place, provide for greater product control.
Example: The application of catalytic zeolites in industrial fields are petrochemical production,
synfuel production, and petroleum refining. The most significant petrochemical catalysts are
synthetic zeolites.
The petrochemical sector uses H-exchanged zeolites, such as ultra-stable zeolite Y (USY), as
solid acid catalysts. Every year, about 300,000 tonnes of synthetic zeolites are produced for
this use.
➢ Household
Domestic usage mostly involves zeolite's capacity to absorb liquids and absorb odors. Zeolite
has been proven to adsorb a variety of gases, including formaldehyde and hydrogen sulphide.

9. Zeolite is frequently added to small air filters in the USA in order to absorb such gases and
lessen allergy issues. It can be used to absorb cigarette odors, dry out athletic shoes, and lessen
dampness in clothing. Zeolite served as the basis material of a very practical carpet cleaner.
Synthetic zeolite is most frequently used in homes as kitty litter and a barbeque grease
absorbent. It is also used to absorb ammonia in fish tanks. The used product, when fully
utilized, is a perfect addition to composts, where it will help.
➢ Molecular and hydrocarbon sieving
Tiny pore zeolites, like zeolite-A, selectively absorb small polar molecules, like water, making
them extremely effective drying agents for getting rid of water vapour from other solvents.
Linear n-alkanes, which are required to manufacture detergents, can be distinguished from
branched alkanes in hydrocarbon sieving because the former move more slowly down a column
of zeolite 5A because they preferentially penetrate its pores, creating a longer path through the
substance. This process generates millions of tonnes of n-alkanes per year.
➢ In medicine
For use in hospitals or by patients, such as those with emphysema and other types of obstructive
pulmonary disease (OPD), there are commercial machines that can give oxygen that is 95%
pure by isolating it from air. Because of a zeolite's substantially greater molecular electric
quadrupole moment, nitrogen (which makes up 80% of air) is preferentially absorbed over
oxygen, allowing oxygen to separate from air almost in a condition of purity. In renal dialysis
equipment, zeolites are also used to absorb ammonia from blood and stop it from accumulating
in the body.
➢ In environmental decontamination
Zeolites are also useful in environmental decontamination techniques. For instance, nearly all
of the zeolite production facilities in the former of USA were monopolized during the cleanup
efforts following the Chernobyl nuclear power plant disaster. In an effort to minimize
radioactive contamination in people, zeolites were baked into bread and biscuits (cookies) for
children as well as fed to cattle to keep radioactive ions out of the milk.

10. References:
Moshoeshoe, M., Nadiye-Tabbiruka, M. S., & Obuseng, V. (2017). A review of the chemistry,
structure, properties and applications of zeolites. Am. J. Mater. Sci, 7(5), 196-221.
Zaarour, Moussa, et al. "Progress in zeolite synthesis promotes advanced applications."
Microporous and Mesoporous Materials 189 (2014): 11-21.
Hardi, Gilar Wisnu, et al. "A Review of Natural Zeolites and Their Applications:
Environmental and Industrial Perspectives." International Journal of Applied Engineering
Research 15.7 (2020): 730-734.
Tao, Yousheng, et al. "Mesopore-modified zeolites: preparation, characterization, and
applications." Chemical reviews 106.3 (2006): 896-910.
Jiří Čejka, Russell E. Morris · Zeolites in catalysis, properties and application 2017
Rhodes, Christopher J. "Properties and applications of zeolites." Science progress 93.3 (2010):
223-284.
https://sctms.ru/docs/presentation/2019/properties-and-applications-of-zeolites.pdf