Chemicals Glossary

Benzene: A simple aromatic hydrocarbon, primarily derived from crude oil via catalytic reforming. It has a large number of industrial applications: used to produce intermediary petrochemicals (styrene, cumene, aniline, cyclohexane) and is used as a solvent. Its other uses are the synthesis of drugs in the pharmaceutical industry, the manufacture of synthetic rubber, the production of lubricants and explosives, polymers and plastic manufacturing, and the production of synthetic dyes and pigments.

Styrene: A derivative of benzene, produced from the dehydrogenation of ethylbenzene. It is a versatile chemical used in polymer production such as polystyrene (also commonly known as Styrofoam), unsaturated polyester resins (important for manufacturing composite materials used in industries such as construction and automotive), formulation of paints, varnishes, and coatings, and the production of adhesives.

Paraxylene: Is one of the three isomers of xylene, primarily derived from crude oil via catalytic reforming. It is a key intermediate in the production of various chemicals, especially in the textile and plastic industries. It is primarily used in the manufacture of purified terephthalic acid (PTA), which is a precursor for polyester production for apparel. It is also crucial in the production of polyethylene terephthalate (PET), commonly used for making water bottles. Paraxylene is also used to produce phthalic anhydride, an ingredient to manufacture plasticizers, reins, and dyes. It is often a solvent in various industrial applications, but has been explored as an additive in fuels.

Toluene: It is a clear, colourless aromatic hydrocarbon with a distinctive sweet odour, derived primarily from petroleum refining and crude oil processing. Its largest use is as a solvent in paints, varnishes, inks, and adhesives, where it dissolves resins and pigments, ensuring smooth application and fast drying. It is also added to gasoline to improve octane ratings, enhancing engine performance and reducing knocking, and is a key precursor in producing benzene, toluene diisocyanate (TDI) for polyurethane foams, trinitrotoluene (TNT), and benzoic acid. In pharmaceuticals, it serves as a solvent for synthesising active ingredients, while in aerospace, automotive, and electronics manufacturing it is widely used for degreasing metal parts and circuit boards. (Also known as Methylbenzene, Toluol, C₇H₈)

Mixed Xylenes: They are a colourless, flammable aromatic hydrocarbon consisting of three distinct isomers — ortho-xylene (o-xylene), meta-xylene (m-xylene), and para-xylene (p-xylene). They are derived primarily from petroleum refining and catalytic reforming of crude oil, and are also blended into gasoline to improve octane ratings. Each isomer has specific industrial value: p-xylene is the most commercially important, used to produce purified terephthalic acid (PTA), a key building block for PET plastics and polyester fibres; o-xylene is used to produce phthalic anhydride, an essential intermediate for plasticizers and flexible PVC; while m-xylene finds use in resins and coatings. As a mixed solvent, they are widely used in paints, inks, adhesives, rubber, and leather industries. They are also used in the manufacture of perfumes, insecticides, and pharmaceuticals.

Methanol: It is one of the world's most widely produced industrial chemicals, with annual global production exceeding 100 million metric tonnes. It is produced by combining carbon monoxide and hydrogen gas in the presence of a catalyst, increasingly using syngas derived from biomass to reduce its carbon footprint. Its largest single use — approximately 30% of global production — is conversion into formaldehyde, a core input for resins, adhesives, plywood, and construction materials. Beyond formaldehyde, it is a key feedstock for acetic acid, MTBE (a gasoline octane booster), and biodiesel, and is widely used as a solvent in pharmaceutical manufacturing. It also serves as a clean-burning fuel and energy carrier, and in wastewater treatment to convert harmful nitrates into harmless nitrogen. (Also known as Methyl Alcohol, Wood Alcohol, CH₃OH)

Phosphoric Acid: It is a strong inorganic acid, derived from phosphate rocks, commonly used in a wide range of industrial applications. It is a vital chemical in many sectors, including agriculture, food production, and manufacturing, with its most significant use being in the production of fertilizers. It is also used for metal & surface treatment, water treatment, in pharmaceutical/cosmetic products, in detergents and cleaners, and in the production of other specialty chemicals.

Sulphuric Acid: It is a highly corrosive, dense, and strong mineral acid, produced primarily from sulphur dioxide, widely used in a variety of industrial processes. It is one of the most important chemicals produced globally and has numerous applications in industries such as chemical manufacturing, petroleum refining, fertilizer production, and metal processing. It is also used to manufacture detergents & surfactants, in water treatment, in the food & beverage industry, in the textile industry, and in the pharmaceuticals industry.

Nitric Acid: It is a highly corrosive and powerful mineral acid. It is produced via the Ostwald process, in which ammonia is oxidized over a platinum or rhodium catalyst at high temperature and pressure. Its largest global use — approximately 80% — is in the production of nitrogen-based fertilizers, most notably ammonium nitrate, which has dramatically increased crop yields worldwide. Beyond fertilizers, it is widely used in the manufacture of explosives like TNT and nitroglycerin, polymers such as nylon, and as a rocket propellant. Its ability to dissolve metals also makes it essential in precious metal refining and metallurgy, as well as in the pharmaceutical, dye, and metal surface treatment industries. (Also known as Aqua Fortis, HNO₃)

Caustic Soda: It is a highly alkaline compound, and the most common method of production is the chlor-alkali process, which involves the electrolysis of saltwater. It is widely used in the chemical manufacturing and cleaning industries for its ability to break down fats, oils, and other organic substances, as well as in the production of various chemicals and materials. It’s also used in the paper, textile, food & beverage, and pharmaceutical industries. It is also used widely in the fertilizer and water treatment industries for pH adjustment, as well as other reasons.(Also known as Sodium Hydroxide, NaOH)

Caustic Potash: It is a highly alkaline compound and a close chemical cousin of Caustic Soda. It is produced through the electrolysis of potassium chloride solution, generating chlorine and hydrogen as by-products. It is widely used in the manufacture of soaps, biodiesel, textiles, batteries, fuel cells, paints, and cleaners, and is the preferred electrolyte in alkaline batteries due to its superior electrical conductivity. It also finds application in petroleum refining, agriculture as a potassium-based fertilizer, and food processing for pH regulation. Compared to Caustic Soda, it costs more to produce and is only chosen when its unique properties justify the premium. (Also known as Potassium Hydroxide, KOH).

Molten Sulphur: It is elemental sulphur in liquid form, heated above 115°C. It is primarily recovered as a by-product of petroleum refining and natural gas processing, where sulphur-containing gases are captured through sulphur recovery units. Its largest use is as a feedstock for producing sulphuric acid via the Contact Process, which is essential for manufacturing fertilizers, detergents, and other chemicals. Beyond sulphuric acid, it is used in the manufacture of pesticides, fungicides, and certain pharmaceuticals. In agriculture, it serves as a soil amendment and natural pesticide. Another industrial use of Molten Sulphur is the vulcanization of rubber. Its transportation and storage require continued heating to prevent solidification. (Also known as Liquid Sulphur, Elemental Sulphur, S)

Urea Ammonium Nitrate (UAN): It is a widely used liquid nitrogen fertilizer that combines urea (a nitrogen-rich compound), ammonium nitrate (a highly soluble nitrogen fertilizer), and water. It is one of the most commonly used fertilizers in agriculture due to its high nitrogen content, which is essential for plant growth. It is highly valued for its ease of application, versatility, and efficiency in delivering nutrients to crops. Its use has revolutionized modern agricultural practices, providing farmers with a versatile and effective means of fertilization.

Calcium Nitrate (CN) solution: It is a highly water-soluble inorganic compound, and it is produced through a neutralization reaction between calcium carbonate and nitric acid, requiring less energy compared to other chemical manufacturing methods. Its primary use is in agriculture, where it is widely favoured in modern farming systems like fertigation and hydroponics, delivering nutrients precisely to the root zone. In construction, it accelerates the setting and hardening of concrete — particularly useful in cold weather — and helps protect steel reinforcement bars from corrosion. It is also used in wastewater treatment to prevent odour formation in sewer networks, and in the pyrotechnics and explosives industries. (Also known as Calcium Dinitrate, Lime Nitrate, Ca(NO₃)₂)

Base Oils: They are the primary building blocks of all lubricants, typically making up 70–90%, with the remainder being performance-enhancing additives. Produced by refining crude oil through heating and distillation, they are used to manufacture lubricating greases, motor oils, and metal processing fluids. Their largest applications are in automotive products — engine oils, transmission and gear lubricants — as well as general industrial lubricants and process oils. Base oils are classified into five groups. Groups I, II, and III are refined from petroleum crude oil, progressing from simpler solvent refining (Group I) through hydrocracking (Group II and III), yielding progressively purer oils with better performance. Group IV base oils are fully synthetic polyalphaolefins (PAOs), offering superior performance across a wider temperature range. Group V covers all remaining base oils not in Groups I–IV, such as silicones, phosphate esters, and bio-lubes.