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Friday 31 January 2014

Toluene as Octane Boaster, Fuel Additives

Sulfuric acid industrial applications

10 major industrial applications of sulfuric acid - king of chemicals

Industrial Applications of Sulfuric Acid


Sulfuric acid referred as universal chemical, king of chemicals due to the numerous applications for sulfuric acid as a raw material or processing agent. Sulfuric acid is the most commonly used chemical in the world and used in almost all industries like

  • Fertilizers
  • Pharmaceuticals
  • Gasoline
  • Automobile batteries
  • Paper bleaching
  • Sugar bleaching
  • Water treatment
  • Sulfonation agents
  • Cellulose fibers
  • Steel manufacturing
  • Coloring agents
  • Amino acid intermediates
  • Regeneration of ion exchange resins

Sulphuric acid is an important industrial chemical which is used in the manufacturing processes of many goods over a wide range of applications. Sulfuric acid used in pulp and paper industry for chlorine dioxide generation, tall oil splitting and pH-adjustments. Over one million tons of sulphuric acid is made each year in the UK alone, with an additional 40 million tones being produced in the USA. Annual worldwide production of sulphuric acid is stands at around 180 million tones.

Sulfuric acid is a strongly acidic, oily liquid that may be clear to cloudy in appearance. Concentrated sulfuric acid acts as both an oxidizing and dehydrating agent. Sulfuric acid is available in many grades ranging from electrolyte grade (33 weight percent) for batteries, to 93 weight percent (66 deg Baume), 98 weight percent, and 20-22 weight percent fuming oleum containing excess dissolved sulfur trioxide. The grade most often shipped is 93 weight percent.

In the environment, sulfuric acid is a constituent of acid rain, since it is formed by atmospheric oxidation of sulfur dioxide in the presence of water. Atmospheric sulfur dioxide is generated by combustion of sulfur-containing fossil fuels such as coal and oil.

Sulfuric acid was once known as oil of vitriol, coined by the 8 th century Arabian alchemist Jabir ibn Hayyan.It was prepared by Johann Van Helmont in the 1600s by destructive distillation of green vitriol (ferrous sulfate) and by burning sulfur. Burning sulfur with saltpeter (potassium nitrate) was first used to prepare sulfuric acid in the 17th century.

By the mid-17th century, John Roebuck had invented the lead chamber process which used nitrogen oxides as oxidant. The contact process, wherein the oxidation of sulfur dioxide to sulfur trioxide is performed by oxygen (air) over a catalyst, was originally developed about 1830 by Peregrine Phillips in England.

In discretionary production, the mining of sulfur or sulfur-bearing minerals (pyrites) is the sole objective, based on the voluntary mining of discrete deposits to obtain maximum economic recovery. In non-discretionary production, sulfur or sulfuric acid is recovered as an involuntary by-product, the quantity of which is subject to demand for the primary product alone.

The lead chamber process has now been almost completely superseded by the contact process in the industrial production of sulfuric acid. Much of the sulfuric acid produced by the lead chamber process is utilized in the making of fertilizers, since the acid is relatively dilute. In contrast, the contact process can make acid of any desired concentration.

Sulfuric acid is a very important commodity chemical, and indeed, a nation's sulfuric acid production has been a reasonably good indicator of its industrial strength for the last century or so.

Here are some of the growing number of end-uses and applications using sulfuric acid


Chemical Manufacturing

As a highly important chemical compound, sulphuric acid is used in the manufacturing process of a number of well-known chemicals including hydrochloric acid, nitric acid, phosphoric acid and many other industrial chemicals.

Oil Refining

The process of refining crude oil requires the use of an acid as a catalyst and Sulphuric acid is often used for this purpose. It is used in a SAAU or sulphuric acid Alkylation Unit.


‘Pickling’ is a term used to describe the treatment of metals to remove impurities, rust or scale from the surface, such as in steel making. Today, the use of sulphuric acid for this purpose has decreased a little as the industry now favours the use of hydrochloric acid. Although hydrochloric acid is more expensive than sulphuric acid, it produces results more quickly and minimizes the loss of base metal during the pickling process.

The Manufacture of Rayon

The textile Rayon is made from cellulose fibres derived from wood. These are dissolved in a solution of Tetra Amine Copper (II) to produce a thick blue liquid which is then injected into sulphuric acid to form Rayon fibres. Rayon is considered to be a good semi-synthetic textile and can rival silk for drape and lustre. Indeed, it is sometimes referred to as ‘art silk’. It is easily dyed and the fabric is soft, cool and smooth. However, unlike silk, Rayon does not insulate body heat so is perfect for use in humid and hot countries.

The Manufacture of Lead-Acid Type Batteries

Sealed-unit lead-acid type batteries are used in the automotive industry for cars and trucks. Sealed-unit lead-acid type batteries were invented in 1859 by Frenchman Gaston Plants. Sulphuric acid is used in a dilute form to act as an electrolye to allow the flow of electrons between the plates in the battery. Sulphuric acid used in this way is commonly called Battery Acid. It can vary in strength according to the battery manufacturer but is generally between 28 to 32 per cent or between 4.2 to 5 Molar.

Potato Harvesting

Potato farmers employ specialist contractors to spray their fields of potatoes before harvesting so that the green tops die back and blacken within a day or two. This helps to dry out the stem and prevents them from becoming tangled in the harvesting equipment. The usual method of spraying potato tops is with a solution of sulphuric acid.

The Manufacture of Medicines

Chemotherapy drugs are used to treat various types of cancer. Cancer cells are more sensitive to DNA damage than normal cells so in chemotherapy treatment cancer cells are destroyed by damaging their DNA. This process is known as alkylation of DNA and a type of drug known as alkylating antineoplastic agents are used. Sulphuric acid is used in the manufacturing process of such drugs

Industrial applications of Toluene - Toluene as fuel octane booster, racing cars fuel additive

Toluene - additive for racing fuels, fuel octane booster

Toluene is an aromatic hydrocarbon solvent often referred as methylbenzene. Toluene is widely used in industry, often served as a substitute for benzene. Methyl side groups present in toluene makes toluene metabolized differently than benzene.

Toluene is well absorbed through the lung, with an alveolar retention of 40 to 80 per cent of an inhaled dose. Air-borne exposure to toluene vapor represents a significant concern to both industrial workers and consumers. Current standards for a permissible exposure limit for toluene at 100 ppm.

Toluene is produced during the process of making gasoline and other fuels from crude oil, in making coke from coal, and as a by-product in the manufacture of styrene. Toluene has numerous commercial and industrial applications and is a solvent in paints, lacquers, thinners, glues, correction fluid and nail polish remover, and is used in the printing and leather tanning processes. Due to its easy accessibility, low cost and ease of concealment, some U.S. states have placed restrictions on the sale of these products to minors.

Toluene is used as a solvent, especially for paints, coatings, gums, oils and resins, and as raw material in the production of benzene, phenol and other organic solvents and in the production of polymers and rubbers. Most amounts of toluene (in the form of benzene-toluene-xylene mixtures) are used in the blending of petrol and it also occurs as a by-product of styrene manufacture.

Toluene is a pure hydrocarbon (C7H8) contains only hydrogen and carbon atoms. It belongs to a particular category of hydrocarbons called aromatic hydrocarbons. Complete combustion of toluene yields two different types of products like carbon dioxide (CO2) and water (H2O). There are no metallic compounds (lead, magnesium etc), no nitro compounds and no oxygen atoms in toluene. Toluene is made up of exactly the same ingredients as ordinary gasoline.

Octane rating/octane number

Octane rating or octane number is a standard measure of the performance of a motor fuel or aviation fuel. The higher the octane number, the more compression the fuel can withstand before detonating. In broad terms, fuels with a higher octane rating are used in high-compression engines that generally have higher performance. In contrast, fuels with lower octane numbers are ideal for diesel engines.
The octane number in vehicles mentioned as Anti-Knock Index (AKI). It’s an average of two octane ratings using the same test equipment but using different operating conditions. The methods produce a Research Octane number (RON) and a Motor Octane Number (MON). With modern engines and fuels systems, recent studies have shown that RON is more important than MON. So in these cars, the higher the RON the better these cars perform. This difference is called sensitivity.

Toluene applications in vehicle additives

Toluene has a RON octane rating of 121 and a MON rating of 107, leading to a (R+M)/2 rating of 114. (R+M)/2 are how ordinary fuels are rated in the US. Toluene has a sensitivity rating of 14 (RON: 121-107 MON). This compares favorably with alcohols, which have sensitivities in the 20 to 30 range. The more sensitive a fuel is the more its performance degrades under load. Toluene's low sensitivity means that it is an excellent fuel for a heavily loaded engine.

Toluene is denser than ordinary gasoline and contains more energy per unit volume. Thus combustion of toluene leads to more energy being liberated and thus more power generated. This is in contrast to oxygenated octane boosters like ethanol or Methyl Tertiary Butyl Ether (MTBE), which contain less energy per unit volume compared to gasoline. The higher heating value of toluene also means that the exhaust gases contain more kinetic energy, which in turn means that there is more energy to drive turbocharger vanes.

Toluene is such an effective anti knock fuel that it takes a smaller quantity to achieve the same octane boost compared to 100 octane racing gas.

Toluene is such an effective anti knock fuel it also means that it is more difficult to ignite at low temperatures. The Formula 1 cars that ran on 84 per cent toluene needed to have hot radiator air diverted to heat its fuel tank to 70oC to assist its vaporization. Thus too strong a concentration of toluene will lead to poor cold start and running characteristics. It’s recommended that the concentration of toluene used not to exceed 30 per cent or what the engine is capable of utilizing.

Reference

Friday 24 January 2014

Sulfuric acid industrial production using contact process




Sulfuric acid chemical formula, Sulfuric acid molar mass, Sulfuric acid molecular weight, Sulfuric acid density
Chemical Properties of sulfuric acid Buy Sulfuric acid, Sulfuric acid manufacturers, Sulfuric acid suppliers
Sulfuric acid manufacturers, Sulfuric acid suppliers

Bio Degradation of Toluene and other volatile organic compounds using jet loop reactor



Read Article on toluene and its industrial applications at world of chemicals
toluene and its industrial applications

Toluene chemical formula, Toluene density, Toluene molecular weight, Toluene boiling point
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Toluene manufacturers and Suppliers

Friday 10 January 2014

Industrial applications Xylene aromatic hydrocarbon mixture three isomers

World of Chemicals Interview with Dr Kongkrapan Intarajang, CEO, Emery Oleochemicals


In an interview with World Of Chemicals News, Dr Kongkrapan Intarajang, CEO, Emery Oleochemicals, gives an update of the current oleochemicals market. He also gives a comparison between the Oleochemical market of Malaysia & China and India.

South East Asia has become the centre of oleochemicals industry, with investment from major companies of the world. What are the factors that make South East Asia a major oleochemicals hub?
The region has successfully developed its feedstock production as well as its chemical transformation industry, offering customers vertical integration and a more reliable and efficient supply chain with many plantations located here.
The existing strong base market in this region, shaped by an increasingly affluent population, drives both demand and innovations in oleochemicals. Its close proximity to other high growth markets such as China and India are additional catalysts as demand continues from the automotive, packaging, building and construction, home and personal care, and agriculture industries.
Emery Oleochemicals uniquely illustrates this dynamism with our global operations headquartered in Malaysia. Benefitting from our access to sustainable feedstock, we continue to expand our manufacturing facility and solutions offering through significant investments in South East Asia (Malaysia). Asia by and large, represents a key geographic market for us.
Major use of oleochemicals is the production of biodiesel. What are the other sources for biodiesel production and what effect it has on the current oleochemicals industry?
Both bio-diesel and oleochemicals are derived from renewable-based feedstock. Where they differ is in its value-adding capabilities and/or supply chain.
The journey of renewable resources in bio-diesel ends at the production of fuel while in oleochemicals, be it basic chemicals (fatty acid, fatty alcohol, glycerine, etc) or specialty chemicals (plastic additives, pelargonic acid, drilling muds, etc) support a myriad of industries ranging from home and personal care, food and beverages, pharmaceuticals, packaging, electronics, automotive, construction, paper, paints and coatings, and many more. 
Oleochemicals production is expanding in India and China, when will India and China be seen in par with the Malaysian oleochemical industry?
China and India oleochemicals business model differs from that of Malaysia with industry players of the former two countries serving mainly in-market demands.
Manufacturers in South East Asia however, have the advantage of more sustainable feedstock supply and are able to support both local needs and that of nearby countries like China and India. With supply chain being one of the key competitive advantages, feedstock proximity plays a big role.
What are the major challenges faced by global oleochemicals industry?
With many new investments from Indonesia-based producers on building new oleobasics capacity, the Oleochemicals industry will eventually face an overcapacity and oversupply issue. This reinforces our strategy in growing the downstream business, where we utilise our own oleobasics products for captive use.
The European oleochemicals industry is increasingly concerned that Commission proposals to reduce the environmental impact of biofuels may well lead to higher greenhouse gas emissions and job losses in Europe. Share your views on the same.
In our opinion, renewable resources have various value-added and economic benefits in many products and/or industries but in bio-diesel the value chain ends at the fuel production. Job creation is certainly a plus point in the making of value-add solutions with industries mentioned earlier (Question 2) being just some of the beneficiaries.
The shale gas discovery has revolutionized the trends in energy sector, how will this affect the biodiesel production from oleochemicals?
The only similarity between oleochemicals and bio-diesel is that they are derived from the same feedstock. How they are being produced, marketed, consumed, are independent from each other. 
The shale gas has revolutionized many industries, including Oleochemicals. Given where the shale gas deposits are largely found, US-based oleochemicals manufacturers/operations will benefit from a cheaper energy source, making products more competitive. In contrary, other industries, including petrochem-based solutions is also enjoying the benefit as well.  
Oleochemicals are derived from plant and animal fats. Does this have any effect on the food sector?
The food industry will take a natural precedence over oleochemicals.  Feedstocks for Oleochemicals  are  either derived from non-edible feedstock (animal fat) or unutilised portion of veg-based feedstock (CPO,CPKO).  Oleochemicals products offer various environmental benefits; as renewable resources that are biodegradable, have low ecotoxicity, and emit no net CO2 to the atmosphere.  These benefits, compared with other products derived from natural-based feedstock (bio-diesel), create benefits to the customers and the environment multiple folds.

sodium hydroxide industrial applications, uses, as cleaning, sanitization agent, chromatography methods

Chemistry of Inks, Dyes and Pigments

Thursday 9 January 2014

Hydrochloric acid, muriatic acid used in carbonate minerals testing | Hydrochloric acid uses

Hydrochloric acid is known as spirits of salt or acidum salis and its formula is HCl. Other name forHCl is muriatic acid. In muriatic acid Muriatic means pertaining to brine or salt. HCl is a strong acid, highly corrosive with many industrial applications.Hydrochloric acid is found naturally in gastric acid.

Hydrochloric acid used in the manufacture of other industrial chemicals like phosphoric acid, chlorine dioxide, ammonium chloride, fertilisers, dyes. HCl is used as a refining ore in the production of tin and tantalum, as a lab reagent, and as a metal treating agent. Muriatic acid is used to remove scale and dust from boilers and heat exchange equipment, to clean membranes in desalination plants, to increase oil well output, to prepare synthetic rubber products by treating isoprene, and to clean and prepare other metals for coatings.

HCl is used in the neutralization of waste streams, the recovery of zinc from galvanized iron scrap, the production of chloride chemicals, the production of vinyl chloride fromacetylene and alkyl chlorides from olefins, the manufacture of sodium glutamate andgelatine, the conversion of cornstarch to syrup, sugar refining, electroplating, soap refining, leather tanning, and the photographic, textile, brewing, and rubber industries. It is used to maintain pH balance in swimming pools, spas, etc.

Hydrochloric acid is also used as a bactericide, a fungicide, and a virucide to disinfect restroom, kitchens and food preparation areas, and in commercial buildings, industrial buildings, in hospitals, in nursing homes, around household dwellings. Hydrochloric acidis used in food processing as a starch modifier.

Worldwide hydrochloric acid production is 20 million tones annually. Hydrochloric acid’s major manufacturers include Dow chemicals, Georgia Gulf Corporation, Tosoh Corporation, Akzo Nobel, and Tessenderlo.

Physical properties

Hydrochloric acid is a solution of hydrogen chloride in water. Hydrogen chloride exists as either a colorless liquid with an irritating, pungent odour or a colorless to slightly yellow gas which can be shipped as a liquefied compressed gas.

Chemical properties

HCl is one of the most corrosive of the non-oxidizing acids in contact with copper alloys, and is handled in dilute solutions. If hydrochloric acid reacted with metals it produces hydrogen gas, which in turn creates the chance of an explosion. It produces poisonous gas, including chlorine, in a fire.

Aqueous hydrochloric acid attack and corrode nearly all metals, except mercury, silver, gold, platinum, tantalum, and certain alloys. It may be colored yellow by traces of iron, chlorine, and organic matter.

Muriatic Acid test for carbonate minerals and carbonated rocks

Carbonate minerals are the major constituents of sedimentary rocks; however, they are also found in igneous and metamorphic rocks, either as primary or as secondary minerals. In carbonate rocks formed either by chemical or mechanical deposition; these minerals constitute the main rock-forming components. Sometimes they are also found in great abundance in pelitic, psammitic and psephitic rocks.

According to most geologists "acid test" means placing a drop of dilute (5 per cent to 10 per cent) hydrochloric acid on a rock or mineral and watching for bubbles of carbon dioxide gas to be released. The bubbles signal the presence of carbonate minerals such as calcite, dolomite or one of the minerals. These minerals are aragonite (CaCO3) witherite (BaCO3), strontianite (SrCO3), cerussite (PbCO3) and alstonite [(Ba,Ca)CO3].

The identification and discrimination of carbonate minerals in hand specimens or thin sections, are made easier by the use of simple chemical staining methods.

It is recommended that the thin section or the cut and polished surface of the hand specimen be etched with diluted HCl acid before staining. Diluted acetic acid or formic acid may also be used in place of HCl acid. Different carbonate minerals in a rock specimen, immersed in an appropriate HCl solution for an appropriate period of time, will show-different reactions. Minerals that show a weak reaction should be treated with warmHCl acid for about 30 seconds to 1 minute.

The bubbling release of carbon dioxide gas can be so weak that you need a hand lens to observe single bubbles slowly growing in the drop of hydrochloric acid or so vigorous that a flash of effervescence is produced. Carbonate minerals are unstable in contact with hydrochloric acid. When acid begins to effervesce (fizz/bubbles) on a specimen a reaction similar to the one shown below is taking place.

Many other carbonate minerals react with hydrochloric acid. Each of these minerals consists of one or more metal ions combined with a carbonate ion (CO3--). The chemistry of these reactions is similar to the calcite reaction above. The mineral reacts with hydrochloric acid to produce carbon dioxide gas, water, a dissolved metal ion and dissolved chlorine.

If you place a drop of hydrochloric acid on powdered dolomite a visible reaction will occur. This is because the surface area has been increased, making more dolomite available to the acid. (You can easily make dolomite powder by scratching a specimen of dolomite across a streak plate.

Some rocks contain carbonate minerals and the acid test can be used to help identify them. Limestone is composed almost entirely of calcite and will produce a vigorous fizz with a drop of hydrochloric acid. Dolostone is a rock composed of almost entirely of dolomite. It will produce a very weak fizz when a drop of cold hydrochloric acid is placed upon it, a more obvious fizz when powdered dolostone is tested and a stronger fizz when hot hydrochloric acid is used.

A few rocks can produce an extreme reaction with hydrochloric acid. These are usually rocks composed of calcite or aragonite with abundant pore space or extremely high surface areas. When a drop of dilute hydrochloric acid is placed on these specimens an eruption of acid foam can rise up off of the rock and spread to an unexpected diameter.

10 major industrial applications, uses Toluene

Toluene is an aromatic hydrocarbon solvent and natural sources of toluene include crude oil and small quantities it is found in tolu tree.Toluene alternative names include methylbenzene, toluol, anisen, phenyl methane.Toluene is produced during the process of making gasoline and other fuels from crude oil, in making coke from coal, and as a by-product in the manufacture of styrene.

Toluene has numerous commercial and industrial applications and is a solvent in paints, lacquers, thinners, glues, correction fluid and nail polish remover, and is used in the printing and leather tanning processes. Methylbenzene can also be used as a fullerene indicator, and is a raw material for toluene diisocyanate.

Toluene as a solvent used in carbon nanotubes like fullerenes. It is also used as cement for fine polystyrene kits as. Biological usage of toluene includes breaking or disrupting red blood cells in order to extract hemoglobin in biochemistry experiments.

Toluene can be used as an octane booster in gasoline fuels used in internal combustion engines. Absolute toluene can be used as a fuel for both two-stroke and four-stroke engines.

One of the cosmetic and personal care products like nail products containing toluene are applied to the hard, largely impenetrable surface of the nail where a smooth and glossy film is quickly formed upon evaporation of the solvents.

Methylbenzene is used to manufacture benzene, urethane raw materials, and other organic chemicals. It is used in the production of pharmaceuticals, dyes, and cosmetic nail products. It is used in agricultural sector against roundworms and hookworms.

Toluene occurs naturally at low levels from crude oil and is usually produced in the processes of gasoline via a catalytic reformer, in an ethylene cracker or making coke from coal. It is widely used in industry, often as a substitute for benzene.

The methyl group which is present in methylbenzene makes it around 25 times more reactive than benzene in such reactions. Methylbenzene undergoes smooth sulfonation to give p-toluenesulfonic acid, and chlorination by Cl2 in the presence of FeCl3 to give ortho and para isomers of chlorotoluene.

Toluene may have local as well as systemic harmful effects. It may cause irritation of the eyes, respiratory tract, and skin. Repeated or prolonged contact with the liquid may cause removal of natural lipids from the skin resulting in dry, fissured dermatitis. Low-level, chronic exposure as well as acute exposure to toluene may result in central nervous system depression and decreased memory. Other symptoms include headache, dizziness, fatigue, muscular weakness, drowsiness, and incoordination with staggering gait, skin paresthesia, collapse, and coma.

The rate of polluted gases in the atmosphere comprises of dissolved organic compounds which affects the environment apparently. One of the best methods to reduce harmful gases in environment is bioreactors.The bioreactors are abundantly used to degrade those substances depending upon various parameters and suitable materials like packing material, microbes, etc. One such dissolved organic compound which is highly toxic to human beings and also present in the gaseous state is Toluene.

A bioreactor is a vessel in which a chemical process is carried out. This process can conducted either be aerobically or anaerobically. These bioreactors are commonly cylindrical, capacity ranging in size from litres to cubic metres, and are made of stainless steel material.

Bioreactor comprises of an

  • Air compressor
  • Oxygen tank
  • Dehumidifier
  • Activated carbon beds
  • Dynamic system for the generation of BTX vapours
  • Foam columns
  • Cell reservoir
  • Deformer
  • Controlling devices

In the field of biochemical engineering, using various types of reactors, including an airlift loop reactor, a bubble column reactor, a stirred tank reactor, and a jet loop reactor etc.

Various techniques have been used for treating toluene

  • Physiochemical treatment methods
  • Bio filtration
  • Bio degradation
  • Thermal oxidation
  • Catalytic oxidation

All these biological treatment methods can convert toluene into

  • Carbon dioxide
  • Water
  • Salt
  • Biomass

Jet loop reactor widely used bioreactor for Volatile organic compounds (VOCs) degradation.

Jet loop reactor

A jet loop reactor (JLR) contains a central draft tube inside the reactor. A bi fluid (liquid and gas) nozzle is located at the top or bottom of the reactor in a structure of two concentric cylinders. The gas delivered through one cylinder is dispersed by the liquid jet stream, delivered through the other cylinder.

The liquid or gas can be circulated back to the reactor to increase the concentration of the gas species in the liquid phase. In JLR toluene is absorbed by circulating nonionic surfactants which is of polyoxyethylene based (LA5 and LA7) Polyol- based and Surfactants.

The toluene removal efficiency was 70 per cent in Tween 81. The removal efficiency of toluene was not affected by Tween 81 which concentration is observed by effects of liquid flow rate. Dissolving oxygen in the water is found to be superior to other reactors interms of oxygen transfer rate per unit power input.

10 Industrial applications Xylene aromatic hydrocarbon mixture three isomers

Xylene characteristics can be described as aromatic hydrocarbon solvent, mixture of three different isomers i.e., meta-xylene, ortho-xylene, para-xylene. Xylol is the other widely used common name for xylene.Xylene appearance described as colorless, sweet-smelling liquid that catches on fire easily.

It is usually refined through an alkylation process from crude oil, also produced as by-product from coal carbonization and can extracted from benzole. Xylene is flammable but of modest acute toxicity, with LD50 ranges from 200 to 5000 mg/kg for animals. Oral xylene LD50 for rats is 4300 mg/kg.

Xylene evaporates quickly from the soil and surface water into the air. In the air, it is broken down by sunlight into other less harmful chemicals. Great variety of consumer products including gasoline, paint, varnish, shellac, rust preventives, and cigarette smoke xylene can be absorbed through the respiratory tract and through the skin.

High levels of exposure for short or long periods can cause headaches, lack of muscle coordination, dizziness, and confusion.

Xylene is origin include both naturally and manmade or synthetic method. It is widely used as a solvent in the leather, rubber, and printing industries. Other various applications of xylene include chemical intermediates, and high-motor and aviation gasoline blending agents, breathing devices (inhalers).

Xylene is used in production of terephthalic acid monomer. It is a good cleaning agent for silicon wafers, steel and to sterilize many substances. Xylene is used as a feedstock in the production of petrol. It is also found in small proportions in gasoline and jet fuel.

Xylene applications in concrete sealer

Acrylic concrete sealer is a decorative concrete material widely used for concrete surfaces. In this type of sealers xylene is used as sealer/carrier solvent.

Xylene can be applied in three ways, all of which depend on the antiquing and/or cleaning method used when the concrete was stamped

In solvent based acrylic sealers, the carrier can be xylene. By applying a coat of xylene, one breaks down or re-melts the coat of sealer that is already on the surface.  When the xylene evaporates from the reconstituted sealer, it leaves the acrylic solids crystal clear and shiny like new.

If the excess antiquing release was not thoroughly removed and is not actually embedded in the cement paste, then scrubbing with xylene will spread the antiquing color around with the melted sealer and will probably create streaking and brush marks when the sealer re-dries. If xylene applied heavily enough, the xylene should melt the sealer all the way to the surface of the concrete before it evaporates.

The third method involves applying straight xylene heavily with a paint roller. This can accomplish the same thing as brushing, but without creating potential brush marks. Applying xylene is a great, inexpensive way to rejuvenate dull or whitened sealer.

Xylene applications

P-Xylene is the principal precursor to terephthalic acid and dimethyl terephthalate, both monomers used in the production of polyethylene terephthalate (PET) plastic bottles and polyester clothing.

O-Xylene is an important precursor to phthalic anhydride.

Xylene is substituted for toluene where slower drying is desired, and thus is used by conservators of art objects in solubility testing.

It is used in the laboratory to make baths with dry ice to cool reaction vessels, and as a solvent to remove synthetic immersion oil from the microscope objective in light microscopy.

In histology, xylene is the most widely used clearing agent.

Xylene is used to remove paraffin from dried microscope slides prior to staining.