Classification of Clay Minerals

Abstract

The versatility of natural clay and their ability to adsorb a variety of environmental contaminants present in the water effluents has attracted esthetic concern among environmentalist. These practical applications rely primarily on the diversity of natural clay structure to retain harmful and undesirable substances from the immediate environment. The adsorptive capability of natural clays is related to the fundamental units of the clay-sized crystalline minerals which present in different combinations.

1. Introduction

The significance of solid mineral resources has been of profound value to man since time immemorial. A mineral is (most of the time) an inorganic crystalline solid, natural, homogeneous, with a structure and a composition that give it defined macroscopic properties. Clays are minerals categorized under the clastic sedimentary rocks. Clay is a naturally occurring material composed of layered structures of fine-grained minerals which exhibit the property of plasticity at appropriate water content but becomes permanently hard when fired [1]. The clay material is formed from chemical alteration processes on the earth’s surface and accounts for approximately 40% of the first-class grained sedimentary rocks (mudrocks) which incorporates dust stones, clay stones and shales. Clayey minerals are usually composed of aluminum silicates that are made up of tetrahedral and octahedral leaves that are bound together collectively via sharing of apical oxygen atoms [2]. The formation of clayey minerals depends on the physical-chemical conditions of the environment of the immediate altering environment, the nature of the raw materials and other related external environmental factors [3]. As such resulting in different types of clay materials. Hence, the potential for application of any clay mineral type in nature will depend on its will depend on its chemistry, structure and other intrinsic properties [1]. Natural clay minerals are widely recognized and acquainted to mankind since the first days of civilization. Owing to their low cost, plenty in most continents of the world, high sorption capability for ion exchange, clay substances are solid candidates as adsorbents [4]. Clay minerals share a fundamental set of structural and chemical traits but yet has its very own precise set of properties that determine its interplay with other chemical species. The variability of chemistry and structure between clays leads to their application in a wide variety of fields.

2. Clay mineral

Clay is usually fine-grained materials, with particle size lower than 0.002 mm with majorly clay minerals. Other minerals related to clay minerals in clays might embody quartz and feldspar, along with detritic materials that have been eroded off the earth’s surface. Clay minerals do not seem to be the most precious among the minerals on the face of the earth, but they affect life on the earth to a great extent. Clay is one of the most ancient mineral substances used by mankind. Clay is a widely dispersed, plentiful mineral resource with substantial industrial significance for a wide range of applications. It is one of the most important minerals in the world, both in terms of value and annual production. The term “clay,” like many geological concepts, is vague and has numerous meanings: clay minerals are a group of fine-grained minerals with a particle size (smaller than silt) and a kind of rock—a fine-grained sedimentary deposit dominated by clay particles. Clay also includes fine-grained non-aluminosilicate deposits like shale and some argillaceous soils under the later definition. It was immensely essential in ancient civilizations, with records kept in brick structures, monuments, and pottery, as well as writings on clay tablets. Clay continues to be a fundamental raw material in today’s world. Clay and clay compounds are now used in far too many ways to mention them all. Clay has a variety of industrial applications, including the manufacture of refractories and drilling mud in the water, oil, and gas sectors. The success of these research hinges on the appropriate exploitation of local raw resources for use as drilling mud in order to achieve long-term economic growth and job creation. Regardless of how abundant clay is and how widely it is used in industry, certain property standards must be satisfied by either raw or refined clay. Clay refining improves the geotechnical qualities of natural clays, potentially increasing their industrial potential. The raw materials used to make mud are generally chosen clays with a significant quantity of montmorillonite, and their behavior in water is utilized to appraise them. Their suitability is decided through numerous criteria, among which can be the viscosity, the volumetric yield of given clay and filtration characteristics. The bentonite clay is the raw material that satisfies the majority of these drilling criteria. Drilling for oil, gas, and water resources often necessitates a large volume of drilling mud, which is frequently imported into the nation. Apart from eroding the country’s hard currency reserves, such importation is also incompatible with the country’s present local content strategy for the oil industry. As a result, the necessity for bentonitic clays or comparable alternatives to be sourced locally has become critical.

2.1 Classification of clay minerals

Clay minerals are classified into different groups as follows; Kaolinite, Smectite, Vermiculite, Illite and Chlorites.

Kaolinite is the purest of all clays, with little variation in composition. It also does not absorb water or expand when it comes into touch with it. As a result, kaolinite Al₂Si₂O₅(OH)₂ is the ceramic industry’s chosen clay. Kaolinite clays have long been used in the ceramic industry, especially in fine porcelains, because they can be easily molded, have a fine texture, and are white when fired. These clays are also used as a filler in making paper. Clay minerals such as kaolinite, hallosite, nacrite, and dickite belong to the Kaolinite group, which is a 1:1 type clay mineral. It is made up of one layer of silica and one layer of alumina, which is created by advanced weathering processes or hydrothermal modifications of feldspars and other alluminosilicates in acidic circumstances [5]. The chemical formula of kaolinite is Al₂O₃.2SiO₂.2H₂O (39% Al₂O₃, 46.5% SiO₂ and 14.0% H₂O) and its structure possesses strong binding forces between the layers which resists expansion when wetted [1]. Kaolin is mostly white in color, has a very tiny particle size, is nonabrasive (hardness 2–2.5 on the Mohs scale), and is chemically inert in most applications. The individual kaolin particle is a thin, flat, pseudohexagonal platelet, so small that if 10,000,000 of them were distributed on a postage stamp, the layer would be thinner than a human hair [1]. In many applications, the thin, flat particle form is advantageous. The particle size and color, or brightness, of commercially available kaolin is used to determine the grade. Kaolin delivers strength, dimensional stability, and smooth surfaces to completed whitewares and sanitary wares by providing a white body, easy molding qualities, and adding strength, dimensional stability, and smooth surfaces. Kaolins are ideal for particular refractories because of their refractoriness, dimensional stability, and chemical inertness. Kaolin’s outstanding dielectric qualities, in addition to the foregoing, make it ideal for porcelain electric insulators. Industrial uses of kaoline includes production of paper, paint, rubber, ceramic, plastic, and medicinal products, as well as a catalyst for petroleum cracking and vehicle exhaust emission control systems, and as a cosmetics foundation and pigment [6]. Furthermore, kaolin is also used as an anti-cracking agent in the manufacturing of fertilizer prills, as a pesticide carrier, in the production of white cement (where it supplies alumina without iron), and in the production of glass fiber as a low-iron, low-alkali alumina source. Kaopectate and Rolaids, for example, are the main ingredients in the original formulation of anti-diarrhea medication in pharmaceutical applications. Through firm and selective binding of aflatoxins, plant secondary metabolites, pathogenic microorganisms, heavy metals, and other poisons in animal diets that could be harmful to the digestive system, kaolin can be used to decontaminate aflatoxins, plant secondary metabolites, pathogenic microorganisms, heavy metals, and other poisons that could be harmful to the digestive system [7]. Naturally, kaolin may be accompanied by other mineral impurities such as feldspar and mica, quartz, titanoferous, illite, montmorillonite, ilmenite, anastase, hematite, bauxite, zircon, rutile, silliminate, graphite, attapugite, halloysite and carbonaceous materials [8] thus reducing its industrial usefulness.

Smectite, which includes montmorillonite, beidellite, nantronite, saponite and hectorite, are 2:1 layer clay minerals formed from the weathering of soils, rocks (mainly bentonite) or volcanic ash and belongs to a group of hydroxyl alumino-silicate [1]. The most common smectite is montmorillonite, with a general chemical formula: (1/2Ca,Na)(Al,Mg,Fe) 4(Si,Al)8O₂₀(OH)₄.nH₂O Smectites are a category of dioctahedral 2:1 expandable minerals having a charge of 0.2–0.6 per formula unit. The octahedral substitution of Mg²⁺ for Al³⁺ gives Montmorillonite, the most prevalent member of this group, its charge. Tetrahedral replacements provide much of the charge in beidellite and nontronite, which are less common in soils. The presence of iron in the octahedral sheet distinguishes nontronite from beidellite. Van der Waals connections and weak cation-to-oxygen links hold the 2:1 layers in smectites together. The presence of exchangeable cations in the interlayer between water molecules causes the crystal lattice to expand as the mineral hydrates. The basal spacing between layers can exceed 2 nm when the material is saturated with water, but it can be lowered to less than 1 ran when the mineral is dry. The major component of bentonite is montmorillinite, which is formed by weathering volcanic ash. When water comes into contact with montmorillinite, it expands by many times its original volume. It may be used as a drilling mud (to keep drill holes open) as well as to seal leaks in soil, rocks, and dams because of this. This expansion and contraction trait found in smectites, often referred to as shrink-swell potential, is problematic to engineers and farmers alike due to the propensity for crack formation and general instability of the soil surface. Montmorillinite, however, is a dangerous type of clay to encounter if it is found in tunnels or road cuts. Because of its expandable nature, it can lead to serious slope or wall failures. Differences in the degree of chemical substitution within the smectite structure, the nature of the exchangeable cations present, and the type and quantity of impurities present induce variation in the physical and chemical characteristics of bentonites within and across deposits [1]. Quartz, cristobalite, feldspars, zeolites, calcite, volcanic glass, and other clay minerals such as kaolinite are all minerals found in smectites [9]. Differences in chemical composition due to replacements of Al³⁺ or Fe³⁺ for Si⁴⁺ in the tetrahedral cation sites and Fe²⁺, Mg²⁺, or Mn²⁺ for Al³⁺ in the octahedral cation sites define the groups of smectite clays. Smectites contain very thin layers and microscopic particle sizes, resulting in a large surface area and hence a high degree of absorbency for a variety of compounds such as oil, water, and other chemicals [1]. Because of their high cation exchange capabilities, surface area, surface reactivity, adsorptive capacity, and catalytic activity, smectites are important minerals for industrial purposes. Bonding foundry sands, drilling fluids, iron ore pelletizing, agriculture (as a carrier material for pesticides, fertilizers, and seed coating), paper making, paints, pharmaceuticals, cosmetics, plastics, adhesives, decolorization, and ceramics are just a few of the applications for this group of clays [10]. The substance is also employed as a clarifier for oils and fats, as well as a chemical barrier, a liquid barrier, and a catalyst [11]. Purification and physicochemical changes of pure smectite are required for the preparation of several high-tech materials such as pillared clays, organoclays, and polymer/smectite-nano ccomposites [1]. Also they are used in many industries; the most important uses are as drilling muds and catalysts in the petroleum industry, as bonding clays in foundries, as bonding agents for taconite pellets, and as adsorbents in many industries. However, the commercial bentonites should contain not less than 60% smectite.

Vermiculite is a high-charge 2:1 phyllosilicate clay mineral. It is generally regarded as a weathering product of micas. Vermiculite is also hydrated and somewhat expansible though less so than smectite because of its relatively high charge. It has a layer charge of 0.9–0.6 per formula unit, and contains hydrated exchangeable cations primarily Ca, and Mg in the interlayer [12]. In soils, vermiculite exists as an Al³⁺ dominated dioctahedral and, to a lesser extent, Mg²⁺ dominated trioctahedral mineral. Water molecules and exchangeable cations—primarily Mg²⁺ and Ca²⁺—are highly adsorbed within the interlayer region of vermiculites due to the tetrahedral charge origin. In vermiculites, unlike smectites, the strong bonding of the interlayer cations binds the 2:1 layers together, restricting basal spacing expansion to 1.5 nm. Vermiculite has a high cation exchange capacity due to its high charge per formula unit, and this clay type has a strong affinity for weakly hydrated cations including K⁺, NH₄⁺, and Cs⁺. The water in raw flakes vermiculite flashes into steam and the flakes expand into accordion-like particles when heated rapidly to 900°C or higher [13], a phenomenon known as exfoliation [14]. Exfoliation, liberates bound water from between the mica-like layers of the mineral and literally expands the layers apart at right angles to the cleavage plane. The expanded or exfoliated material is low in density, chemically inert and adsorbent has excellent thermal and acoustic insulation properties, is fire resistant and odorless. Granular clay absorbents, such as vermiculite, have been used for over 75 years to clean up minor drips, spills and over sprays in factories and garages. Vermiculite is used to loosen and aerate soil mixes. Mixed with soil, it improves water retention and fertilizer release, making it ideal for starting seeds. Also used as a medium for winter storage of bulbs and flower tubers. The common applications of exfoliated vermiculite include making of friction light weight aggregates, thermal insulator, brake linings, various construction products, animal feeds and in horticulture [1]. Vermiculite in fertilizers improves the efficiency with which nutrients are released, making fertilizers more cost-effective for customers [15]. Vermiculite’s layered structure and surface qualities allow it to be employed in intumescent coatings and gaskets, as well as the treatment of hazardous waste and air freight. The internal pressure generated by the expansion of vermiculite when heated is sufficient to crush hard rock during tunneling activity [16]. Other minerals such as feldspars, pyroxenes, amphiboles, carbonates, and quartz, which develop alongside vermiculite in the rock and appear as major components, as well as minor components such as phosphates, iron oxides, titanium oxides, and zircon, can be found in vermiculite ores. Some impurities, such as asbestiform amphibole minerals present in vermiculite, have a negative impact on human health, as they can cause illnesses like malignant mesothelioma, asbestosis, or lung cancer; hence, clay characterization is necessary to detect such impurities [1].

Illite is the most frequent clay mineral, accounting for more than half of the claymineral suite in the deep sea. It is comparable to muscovite. They form in temperate climates or at high altitudes in the tropics, and they generally reach the ocean by rivers and wind transmission. Illite clays have a structure similar to muscovite, although they are generally low in alkalies and contain less Al substitution for Si. As a result, the typical formula for illites is KyAl4(Si8-y,Aly)O20(OH)4, with 1 < y < 1.5, but always with y < 2. Ca and Mg can occasionally be used in place of K due to a charge imbalance. The interlayer cations of K, Ca, or Mg prohibit H₂O from entering the structure. As a result, the illite are non expanding clays. Clay micas are another name for the illite clay mineral group. Mica is a phyllosilicate mineral that may be split or delaminated into thin sheets that are platy, flexible, clean, elastic, transparent to opaque, robust, reflecting, refractive, dielectric, chemically inert, insulating, light weight, and hydrophilic [1]. Mica minerals’ atoms are bound together into flat sheets, allowing for flawless cleavage of the minerals to generate durable sheets in a variety of colors, including brown, green, black, violet, and colorless, with a vitreous to pearly shine [17]. There are around 30 members of the mica group, but muscovite, biotite, phlogopite, lepidolite, fuchsite, and zinnwaldite are the six most frequent forms found in nature and employed in microscopy and other analytical applications [1]. Clay minerals are made up of three members (the illite group), which include illite, glauconite, and muscovite, and display clay-like characteristics, with illite being the most frequent. Illite is generated by alkaline weathering of potassium and aluminum-rich rocks such as muscovite and feldspar. Illite is a 2:1 layer silicate clay mineral that is non-expansive due to poorly hydrated potassium cations or calcium and magnesium ions filling the gap between the crystals of individual clay particles, preventing water molecules from entering the clay structure. Illite’s cation exchange capacity ranges from 20 to 40 meq per 100 g. Minerals range in color from gray white to silvery white to greenish gray. Because of their high potassium concentration, illites are used in the structural clay industry and in agro minerals [18]. Quartz, feldspar, kaolin, and pyroxene are among the impurities found in mica clay ores [19]. The presence of these minerals in mica ores will affect the industrial value of the deposits as well as the processing complexity, lowering or boosting their value depending on the uses [20].

Chlorites are hydrous aluminosilicates with an interlayer organized in a 2:1 configuration. Chlorites are fundamental minerals found in soils that weather to generate vermiculite and smectite. Interlayered hydroxy-Al vermiculites or smectites, on the other hand, are regarded secondary minerals that develop as intermediate mineral weathering products or by the deposition of hydroxy-Al polymeric components inside the interlayer space of expanding minerals. There is no water adsorption within the interlayer space; thus, chlorites are considered nonexpansive minerals. These hydroxy-Al polycations balance a portion of the charge but they are not interchangeable. The CEC of the expandable 2:1 clays is lowered as a function of the quantity and valence of the hydroxy-Al polymer dwelling within the interlayer space because the level of hydroxy-Al occupancy within the interlayer space is varied. In the octahedral sheet inside the 2:1 layer and in the interlayer hydroxide sheet, they incorporate mostly Mg, Al, and Fe cations, with lesser amounts of Cr, Ni, Mn, V, Cu, and Li cations. In the tetrahedral sheet, they also show a substantial replacement of Si by Al cations [21]. Chlorites range in color from white to practically black or brown with a green tinge, and their optical qualities are linked to their chemical makeup [22]. In the study of phase interactions in low and intermediate grade metamorphic rock, understanding the chemical composition of chlorite is crucial [23]. The first mineralogical and chemical investigation of clay ores can be used to determine the appropriateness of the material for various uses, given the diversity of clay mineral groups in nature.

2.2 Other minerals found in clay

In addition to the phyllosilicates mentioned, the soil clay fraction may also contain minor amounts of oxides, hydroxides, and hydroxy-oxides (sesquioxides) of Si, Al, and Fe, as well as some weakly crystalline aluminosilicates. Quartz (owing to its excellent resistance to weathering) and opal (a weakly crystalline variant of quartz that precipitates from Si-supersaturated fluids or is of volcanic or biogenic origin) are two common Si-oxide minerals found in the clay fraction. Gibbsite (Al(OH)₃) is the most prevalent Al-hydroxide representative in severely worn soil clay fractions, whereas goethite (FeOOH) is the most common Fe-mineral in clay fractions. Allophane and imogolite, two weakly crystalline aluminosilicate clay minerals, are commonly found in clay fractions of volcanic soils. The primary varieties of commercial clays include ball clay, common clay and shale, and fire clay, in addition to bentonite (and Fuller’s earth) and kaolin. Ball clay is mostly kaolinite, with traces of illite, chlorite, smectite minerals, quartz, and organic matter.

3. Applications of some essential clay minerals

3.1 Bentonite

The word “bentonite” is a bit of a misnomer. It is a rock consisting of extremely colloidal and plastic clays, mostly montmorillonite, a clay mineral of the smectite group, and created by in situ devitrification of volcanic ash, according to geologists [24]. Bentonite generated from ash falls is usually found in uniformly thick strata (ranging from a few millimeters to 15 meters) that cover enormous regions [24]. It is found in layers from ash falls and other sources all throughout the planet, although it is most plentiful in Cretaceous and newer rocks.

Bentonite is a rock made up of extremely colloidal and malleable clays, mostly montmorillonite, a smectite group clay mineral, that is created by devitrification of volcanic ash in situ. Bentonite may also contain feldspar, cristobalite, and crystalline quartz in addition to montmorillonite. The ability to produce thixotrophic gels with water, the ability to absorb huge amounts of water, and a high cation exchange capacity are all characteristics of bentonite.

In the foundry business, bentonites are used to bind sands into suitable forms in which metals may be cast. To hold the sand grains together, just 3–5% bentonite is required. Bentonites have a greater green, dry, and hot strength than any other form of clay due to their tiny particle size and the nature of their water adsorption. The taconite industry is quickly increasing the usage of bentonite as a bonding agent [25]. A variety of sodium bentonite’s unique features are used in hazardous waste containment. Because of its swelling capacity, bentonite is an efficient soil sealant, since it fills the gaps in the soil by expanding inside the interstices of the soil with which it is combined, forming a very low permeability barrier. The capacity of bentonite to swell is facilitated by the potential of a very tiny average particle size, which allows it to fill even the tiniest of spaces. The strong cation exchange capacity improves waste retention, particularly for heavy metals. A combination of sodium bentonite and dirt also generates a stiff, flexible mastic that is exceptionally resistant and difficult to rupture. The capacity of bentonite to bind cationic metals and some pesticides has been used in experiments to detoxify paraquat poisoning patients and to reduce radiocaesium transfer to milk and other animal-derived foods.

3.2 Kaolinite

The word “kaolin” comes from the Chinese word Kau-Ling, which means “high ridge,” and refers to a hill near Jau-chau Fu, where kaolin was first mined [26]. Kaolin, often known as china clay, is a clay that comprises 10–95% kaolinite and is generally composed primarily of kaolinite (85–95%).

Kaolin, sometimes known as china clay, is a mineral combination. Kaolinite is the primary component, however it also contains quartz, mica, feldspar, illite, and montmorillonite. Kaolinite is made up of triclinic crystal sheets with pseudohexagonal shape. Rock weathering is responsible for its formation. It has the ability to exchange cations. There are three methods for kaolinite to form:

• crumbling and transformation of rocks due to the effects of climatic factors (Zettlitz type);

• transformation of rocks due to hydrothermal effects (Cornwall type); and.

• formation by climatic and hydrothermal effects (mixed type).

The use of kaolin as a paper coating accounted for about half of total domestic consumption and roughly 80% of kaolin exports. Kaolin-coated papers are widely used in the production of cigarettes [24]. Smokers may be exposed to kaolinite particles by inhaling. Kaolin was also used as a filler in the manufacture of paint, paper, and rubber, as a component of fiber glass and mineral wool, as a landfill liner, and as a catalyst in the refinement of oil and gas. Historically, the use of kaolin in the making of porcelain and chinaware amounted for less than 1% of total domestic consumption in the United States. In 2003, ceramics accounted for 80–85% of overall manufacturing in China, with paper accounting for 5%, rubber for 3%, and paint accounting for 2%. Ceramics consumed 290,000 tonnes, paints 84,000 tonnes, paper/paperboard 68,000 tonnes, detergents 29,000 tonnes, and rubber 27,500 tonnes in India. Kaolinite has a variety of medically useful qualities. It is a good adsorbent that will adsorb not just lipids and proteins but also other substances [24] including viruses and bacteria [27]. It can be used to cause platelet aggregation and to start plasma coagulation by activating factor XII. [28] Also, non-specific haemaglutinin inhibitors should be removed from the serum. Kaolin is utilized as a local and gastrointestinal adsorbent in medicinal treatment (Kaopectate, bolus alba). Kaolin may be found in a variety of cosmetics, including eyeshadows, blushers, face powders, “powders,” mascaras, foundations, and makeup bases. Kaolin was found in 509 different cosmetics in the United States in 1998, with concentrations ranging from 5 to 30%, but exceeding 84% in certain paste masks [29]. Medical, pharmaceutical, and cosmetic applications, on the other hand, accounted for around 0.01% of total kaolin usage in the United States.

4. Clay minerals AS potential application IN water purification

The assessment of water quality using the Water Quality Index (WOI) and every available means are being developed and used by researchers [30] and [31] applied the WOI assessment to the evaluation and validity of a river region with a single number that checked the multiple drinking water criteria The findings were able to certify whether the water was safe to drink or not, based on the set of criteria. Before being deemed safe for use, drinking water and water used for other purposes must be free of these toxins in order to encourage a healthy lifestyle free of illnesses linked to waterborne diseases [32]. Filtration, which is a typical procedure used in water purification, is one approach to remove harmful toxins. It entails the use of a medium, such as a membrane or aggregates, as well as the use of a membrane or aggregates. While adsorbing and absorbing pollutants on the media, filtration employs both physical and chemical processes. Ceramic (clay) membranes for point-of-use filtration, cloth or fiber membranes, compressed granular activated carbon (GAC), polymer membranes, sand, gravel, or crushed rock, and clay aggregates are only a few examples of filtration medium. Artifacts, medications, construction materials, electrochemical research, cosmetics, pharmaceuticals, earthen products, and agriculture are just a few of the economic benefits of clay [33], clay has played a vital role in water purification technology. Clay ceramic water filters have shown capabilities in removing water contaminants such as microbes [34], chemicals [18] and heavy metals. Ceramic water filters made from clay and clay minerals are very efficient for water filtration through adsorption/absorption, molecular sieving and ion exchange mechanisms [35]. Clay is also affordable, plentiful, ubiquitous, and easily accessible. User friendliness, cultural tolerance, and cheap maintenance costs are further factors to consider. Many scientific and technological advancements have been attributed to the characterization of materials in order to establish their important features for optimal use and application. Clay and clay minerals’ suitability for use in water filtration media and other industrial applications is determined by their mineralogy, chemical composition, mechanical properties (such as plasticity), specific surface area, porosity, functionality, and structure, as well as their interactive behavior.

5. Conclusions

In this study, it has been established that clay minerals may appear not to be the most valuable among the minerals of the earth surface, yet they affect life on earth in far reaching ways. Little would be known to man in ages past that the uses of clay surpass molding bricks and all sort. Recent studies have shown that some of it classes are used for intumescent coatings and gaskets, treatment of toxic waste and air-freight. Due of its characteristic plastic property, clay has several industrial uses, which include manufacturing of refractories as well as in drilling mud in the water, oil and gas industries. Today, natural clay derivatives, a group of low-cost adsorbents, naturally with the hydrophilic characteristics have emerged to be a new solution to control the mobility and emission of water pollutants in the groundwater tables. Specifically, these unique adsorbents and its modified derivatives are found capable to remove anionic contaminants, hydrophobic or nonpolar organic pollutants through the interlayer (quaternary ammonium cations) exchange process.

Acknowledgments

My sincere gratitude goes to Almighty God for the gift of life, His grace, wisdom, knowledge and understanding, provisions, sound health and mind in the course of this write-up. Also, my profound gratitude goes to my parents; Pst. and Pst. (Mrs.) A.A. Akisanmi for their immerse support and inestimable love shown from the start of this write-up, it is unquantifiable. To my siblings; Peace and Precious, you are highly appreciated.