What do VOC, VOCs, TVOC mean? Distinguis
Voc usually refers to an organic compound that is easily volatilized at normal temperature. More common are benzene, toluene, xylene, ethylbenzene, styrene, formaldehyde, tvoc (6-16 carbon alkanes), ketones and the like. These compounds are highly volatile and lipophilic and are widely used in industries such as footwear, toys, paints and inks, adhesives, cosmetics, interior and automotive decorative materials.
For the concept of volatile organic compounds (voc), different standards in different countries have different definitions:
1 World Health Organization (Who) defines voc as a general term for volatile organic compounds having a melting point below room temperature and a boiling point between 50 and 260 °C;
2 The US astm d3960-98 standard defines voc as any organic compound that can participate in atmospheric photochemical reactions;
3 The US Federal Environmental Protection Agency (epa) defines voc as any carbon compound that participates in atmospheric photochemical reactions except co, co2, h2co3, metal carbides, metal carbonates, and ammonium carbonate;
4 EU Directive 2002/231/ce defines volatile organic compounds as organic chemicals with high vapor pressure and easy evaporation at normal temperature and pressure;
5 EU Directive 2004/42/ce defines volatile organic compounds (voc) as any organic compound with an initial boiling point lower than or equal to 250 ° C at a standard pressure of 101.3 kPa;
6gb50325-2001 Indoor Environmental Pollution Control Code for Civil Buildings Definitions Volatile organic compounds are organic compounds that can participate in gas phase photochemical reactions.
7 Australia's National Contaminant List defines all organics with a vapor pressure greater than 0.27 kpa at 25 °C.
Vocs is the abbreviation of volatile organic compounds, which refers to organic compounds with a saturated vapor pressure greater than 70.91pa at room temperature and a boiling point of less than 260 °C at atmospheric pressure. Voc and vocs are actually the same kind of substance, that is, the English abbreviation of volatile organic compounds. Because volatile organic compounds generally have more than one kind of ingredients, vocs are more precise. Moreover, in the daily communication process, people habitually save s, causing some friends to confuse voc and vocs?
From the perspective of environmental monitoring, it refers to the total name of non-methane total hydrocarbons detected by hydrogen flame ion detector, mainly including alkanes, aromatics, olefins, halocarbons, esters, aldehydes, Ketones and other organic compounds.
Tvoc is an abbreviation for total volatile organic compounds, ie total volatile organic compounds. The World Health Organization (Who, 1989) defines tvoc as a general term for volatile organic compounds with melting points below room temperature and boiling points ranging from 50 to 260 °C.
The three main sources of vocs: coal, oil, natural gas:
The sources of vocs are classified into fixed sources and mobile sources. Coal, oil and natural gas or industries that use coal, oil and natural gas as fuel or feedstocks are the three most important sources of volatile organic compounds.
Classification vocs component
Alkanes, ethane, propane, butane, pentane, hexane, cyclohexane
Olefins, ethylene, propylene, butene, butadiene, isoprene, cyclopentene
Aromatic hydrocarbons and their derivatives benzene, toluene, xylene, ethylbenzene, cumene, styrene, phenol
Aldehydes and ketones Formaldehyde, acetaldehyde, propionaldehyde, methyl ethyl ketone, methyl acetone, ethyl acetone
Aliphatic hydrocarbon methyl acrylate, dibutyl phthalate, vinyl acetate
Alcohol methanol, ethanol, isoprene, butanol, pentanol
Ethylene glycol derivative methyl cellosolve, ethyl cellosolve, butyl cellosolve, methoxypropanol
Acids and anhydrides acetic acid, propionic acid, butyric acid, oxalic acid, phthalic anhydride
Amines and amides Aniline, dimethylformamide
Types of emission vocs in industrial production