Polycyclic aromatic hydrocarbons (PAHs), benzene and toluene (BT) are ubiquitous toxic pollutants in the environment.
Is BTEX a type of PAH?
Polycyclic Aromatic Hydrocarbons (PAHs) and Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) Contamination of Soils in Automobile Mechanic Workshops in Port-Harcourt Metropolis, Rivers State, Nigeria. had the highest concentration of PAHs (3.678 ± 0.036 mg/kg) and BTEX (0.013 ± 0.003 mg/kg).
What is polycyclic aromatic hydrocarbons made of?
A polycyclic aromatic hydrocarbon (PAH) is a hydrocarbon—a chemical compound containing only carbon and hydrogen—that is composed of multiple aromatic rings. The group is a major subset of the aromatic hydrocarbons.
What are aromatic amines found in?
Aromatic amines are chemicals found in industrial and manufacturing plants, tobacco smoke, commercial hair dyes, and diesel exhaust.
How many polycyclic aromatic hydrocarbons are there?
Over 100 PAHs have been identified in atmospheric particulate matter and about 200 in tobacco smoke. PAHs have very low water solubility, and are soluble in many organic solvents and highly lipophilic.
Is benzene a VOC?
Common examples of VOCs that may be present in our daily lives are: benzene, ethylene glycol, formaldehyde, methylene chloride, tetrachloroethylene, toluene, xylene, and 1,3-butadiene.
Are BTEX hydrocarbons?
In the petroleum refining and petrochemical industries, the initialism BTX refers to mixtures of benzene, toluene, and the three xylene isomers, all of which are aromatic hydrocarbons. … If ethylbenzene is included, the mixture is sometimes referred to as BTEX.
What does BTEX stand for?
BTEX refers to the chemicals benzene, toluene, ethylbenzene and xylene. These compounds occur naturally in crude oil and can be found in sea water in the vicinity of natural gas and petroleum deposits.
What does PAH stand for in terms of organic chemistry?
Polycyclic aromatic hydrocarbons (PAHs) are a large group of organic compounds with two or more fused aromatic rings. They have a relatively low solubility in water, but are highly lipophilic.
Is indole a PAH?
PANHs are polycyclic aromatic nitrogen heterocycles (e.g., indole, acridine; note that the H stands for “heterocycle” and not “hydrocarbon”);
Is Indene a PAH?
Indene, the simplest PAH with single five- and six-membered rings, was predicted theor. to be formed through the reaction of benzyl radicals with acetylene.
What does the word polycyclic mean?
: having more than one cyclic component especially : having two or more rings in the molecule.
What is xylene in chemistry?
Xylene is an organic chemical compound which is also called dimethyl benzene or xylol. It is one of the three isomers of the compound dimethylbenzene. It consists of a central benzene ring which is attached with two methyl groups as substituents.
What is benzene toluene and xylene?
Benzene/Toluene/Xylene Mixture (BTX), also known as Hydrogenated Pyrolysis Gasoline (HPG), is a clear liquid with an aromatic odor. BTX/HPG is a co-product of ethylene production and is produced in closed systems that are monitored and controlled.
Is xylene biodegradable?
Xylene is stable to hydrolysis and oxidation in the aquatic environment, but is expected to undergo biodegradation.
Why benzene is volatile?
Benzene belongs to a class of chemicals called volatile organic compounds, so called because they evaporate in the air.
How are VOCs made?
VOCs typically are industrial solvents, such as trichloroethylene; fuel oxygenates, such as methyl tert-butyl ether (MTBE); or by-products produced by chlorination in water treatment, such as chloroform. VOCs are often components of petroleum fuels, hydraulic fluids, paint thinners, and dry cleaning agents.
Why is PAH bad?
Why are PAHs bad actors? PAHs are a concern because they are persistent. Because they do not burn very easily, they can stay in the environment for long periods of time.
What is the difference between polynuclear and polycyclic aromatic hydrocarbons?
The key difference between polycyclic and polynuclear aromatic hydrocarbons is that the term polycyclic aromatic hydrocarbon describes the presence of two or more cyclic structures fused to each other whereas the term polynuclear aromatic hydrocarbon describes the presence of more than one atom.
What is a polycyclic molecule?
A polycyclic compound is one whose molecules contain two or more rings joined to each other. Environmentally, the most important polycyclic organic compounds are the polycyclic aromatic hydrocarbons , also known as polynuclear aromatic hydrocarbons (PAHs).
What are the types of aromatic compounds?
Aromatic compounds are broadly divided into two categories: benzenoids (one containing benzene ring) and non-benzenoids (those not containing a benzene ring) for example, furan. Any hydrocarbon can be classified as an aromatic compound provided they follow the Huckel rule.
How do you identify aromatic amines?
An aromatic amine is an organic compound consisting of an aromatic ring attached to an amine. It is a broad class of compounds that encompasses anilines, but also many more complex aromatic rings and many amine substituents beyond NH2.