VOC exempt solvents are organic compounds that are exempt from restrictions placed on most volatile organic compounds (VOCs) in the United States. [1] [2] [3] [4] [5] This class of solvent currently includes acetone, dimethyl carbonate, methyl acetate, parachlorobenzotrifluoride (Oxsol 100), tert-Butyl acetate, [6] and propylene carbonate. [7] The definition is often that they do not contribute to ozone or ozone depletion. [8]
In the US, dimethyl carbonate was exempted under the definition of volatile organic compounds (VOCs) by the U.S. EPA in 2009. [9] Due to its classification as VOC exempt, dimethyl carbonate has grown in popularity and applications as a replacement for methyl ethyl ketone (MEK) and other solvents. tert-Butyl acetate is used as a solvent in the production of lacquers, enamels, inks, adhesives, thinners and industrial cleaners. [10] [11] It also gained EPA VOC exempt status.
VOC exempt solvents are used in applications where traditional solvents are used. These include Coatings, Adhesives, Sealants and Elastomers.
VOC exempt status does not mean that the solvent is non-flammable and thus safety must be carefully considered. For example, Acetone has an extremely low flash point and care is needed when handling.
In chemistry, an ester is a functional group derived from an acid in which the hydrogen atom (H) of at least one acidic hydroxyl group of that acid is replaced by an organyl group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well, but not according to the IUPAC.
Butanone, also known as methyl ethyl ketone (MEK) or ethyl methyl ketone, is an organic compound with the formula CH3C(O)CH2CH3. This colorless liquid ketone has a sharp, sweet odor reminiscent of acetone. It is produced industrially on a large scale, but occurs in nature only in trace amounts. It is partially soluble in water, and is commonly used as an industrial solvent. It is an isomer of another solvent, tetrahydrofuran.
Dichloromethane is an organochlorine compound with the formula CH2Cl2. This colorless, volatile liquid with a chloroform-like, sweet odor is widely used as a solvent. Although it is not miscible with water, it is slightly polar, and miscible with many organic solvents.
Methyl tert-butyl ether (MTBE), also known as tert-butyl methyl ether, is an organic compound with a structural formula (CH3)3COCH3. MTBE is a volatile, flammable, and colorless liquid that is sparingly soluble in water. Primarily used as a fuel additive, MTBE is blended into gasoline to increase its octane rating and knock resistance, and reduce unwanted emissions.
Volatile organic compounds (VOCs) are organic compounds that have a high vapor pressure at room temperature. High vapor pressure correlates with a low boiling point, which relates to the number of the sample's molecules in the surrounding air, a trait known as volatility.
Paint thinners are diluents and usually refers to a solvent that is used to dilute or "thin" oil-based paints — and similar things, such as varnish, which in essence are a colloidal suspension of a solid dispersed in a liquid medium — to reduce the viscosity and so making them 'more liquid'. Typically, this happens after the paint has lost some of the solvent while in storage, so have become too thick and dried-out for use.
Methyl acetate, also known as MeOAc, acetic acid methyl ester or methyl ethanoate, is a carboxylate ester with the formula CH3COOCH3. It is a flammable liquid with a characteristically pleasant smell reminiscent of some glues and nail polish removers. Methyl acetate is occasionally used as a solvent, being weakly polar and lipophilic, but its close relative ethyl acetate is a more common solvent being less toxic and less soluble in water. Methyl acetate has a solubility of 25% in water at room temperature. At elevated temperature its solubility in water is much higher. Methyl acetate is not stable in the presence of strong aqueous bases or aqueous acids. Methyl acetate is not considered a VOC in the USA.
Acetylacetone is an organic compound with the chemical formula CH3−C(=O)−CH2−C(=O)−CH3. It is classified as a 1,3-diketone. It exists in equilibrium with a tautomer CH3−C(=O)−CH=C(−OH)−CH3. The mixture is a colorless liquid. These tautomers interconvert so rapidly under most conditions that they are treated as a single compound in most applications. Acetylacetone is a building block for the synthesis of many coordination complexes as well as heterocyclic compounds.
Acetone is an organic compound with the formula (CH3)2CO. It is the simplest and smallest ketone. It is a colorless, highly volatile, and flammable liquid with a characteristic pungent odour, very reminiscent of the smell of pear drops.
tert-Butyl alcohol is the simplest tertiary alcohol, with a formula of (CH3)3COH (sometimes represented as t-BuOH). Its isomers are 1-butanol, isobutanol, and butan-2-ol. tert-Butyl alcohol is a colorless solid, which melts near room temperature and has a camphor-like odor. It is miscible with water, ethanol and diethyl ether.
n-Butyl acetate is an organic compound with the formula CH3CO2(CH2)3CH3. A colorless, flammable liquid, it is the ester derived from n-butanol and acetic acid. It is found in many types of fruit, where it imparts characteristic flavors and has a sweet smell of banana or apple. It is used as an industrial solvent.
tert-Butyl acetate, t-butyl acetate or TBAc is a colorless flammable liquid with a camphor- or blueberry-like smell. It is used as a solvent in the production of lacquers, enamels, inks, adhesives, thinners and industrial cleaners. It has recently gained EPA volatile organic compound (VOC) exempt status.
Propylene carbonate (often abbreviated PC) is an organic compound with the formula C4H6O3. It is a cyclic carbonate ester derived from propylene glycol. This colorless and odorless liquid is useful as a polar, aprotic solvent. Propylene carbonate is chiral, but is used as the racemic mixture in most contexts.
Dimethyl carbonate (DMC) is an organic compound with the formula OC(OCH3)2. It is a colourless, flammable liquid. It is classified as a carbonate ester. This compound has found use as a methylating agent and as a co-solvent in lithium-ion batteries. Notably, dimethyl carbonate is a weak methylating agent, and is not considered as a carcinogen. Instead, dimethyl carbonate is often considered to be a green reagent, and it is exempt from the restrictions placed on most volatile organic compounds (VOCs) in the United States.
Solution polymerization is a method of industrial polymerization. In this procedure, a monomer is dissolved in a non-reactive solvent that contains a catalyst or initiator.
Parachlorobenzotrifluoride is a synthetic halogenated organic chemical compound with the molecular formula C7H4ClF3. It is frequently abbreviated PCBTF. Parachlorobenzotrifluoride is a colorless liquid with a distinct aromatic odor. PCBTF has been commercially-produced since the 1960s, initially as an intermediate in the production of other petrochemicals. But since the 1990s, it has been primarily used as a solvent.
Isopropyl alcohol is a colorless, flammable organic compound with a pungent alcoholic odor.
The environmental impact of paint can vary depending on the type of paint used and mitigation measures. Traditional painting materials and processes can have harmful effects on the environment, including those from the use of lead and other additives. Measures can be taken to reduce its environmental effects, including accurately estimating paint quantities so waste is minimized, and use of environmentally preferred paints, coating, painting accessories, and techniques.
In an oil and gas production, flash-gas is a spontaneous vapor that is produced from the heating or depressurization of the extracted oil mixture during different phases of production. Flash evaporation, or flashing, is the process of volatile components suddenly vaporizing from their liquid state. This often happens during the transportation of petroleum products through pipelines and into vessels, such as when the stream from a common separation unit flows into an on-site atmospheric storage tank. Vessels that are used to intentionally “flash” a mixture of gas and saturated liquids are aptly named "flash drums." A type of vapor-liquid separator. A venting apparatus is used in these vessels to prevent damage due to increasing pressure, extreme cases of this are referred to as boiling liquid expanding vapor explosion (BLEVE).