Production
The complete process of coal tar production is shown in Figure 1. The coal tar is produced by carbonization of coal. In this process, the coal is heated at 900-1100 ºC and the evolved vapors are condensed to form liquid, from which ammonia is removed to obtain a black viscous crude coal tar. The composition of tar so obtained depends upon the origin and composition of starting material used viz. bituminous (soft) coal, anthracite (hard) (Arnold 1997, Thami 2002).
Crude coal tar can be further purified using various techniques viz. solvent extraction, fractional distillation or coloum chromatography. The extraction of crude coal tar with alcohol containing 5% w/w Tween 80 produces Liquor carbonis detergens (LCD). Similarly, the distillate and residue obtained after fractional distillation of CCT are known as coal tar creosotes and coal tar pitch respectively. The creosotes consist of light oils (2-8%), middle oils (8-10%), heavy oils (8-10%) and anthracene oils (16-20%) (Gosselin et al. 1984). Pitch is mostly made up of highly condensed aromatic hydrocarbons (Kershaw 1993). Medical pix lithantracis is a mixture of pitch (66.67%) and tar oils (33.33%) (Roelofzen 2007).
Physical and chemical characteristics
Crude coal tar is a black and viscous liquid. It has obnoxious naphthalene like odor and a prickly burning taste (Gennaro1990). It is heavier than water. It is “practically insoluble” in water, whereas “all or almost all” dissolves in benzene or nitrobenzene (Budavari 1989).
According to EPA 1994 & IARC 1985, CCT contains approximately 10,000 compounds which consist of 48% hydrocarbons, 42% carbon and 10% water. The chemical composition of coal tar depends upon the temperature of distillation (IARC Monogr Eval C...
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...rmulation in mice (Bhatia 2009, 2011).
The therapeutic benefits of coal tar are the results of synergistic or additive effects of its more than thousand chemical constituents whose concentrations vary depending upon the source and distillation conditions. There is also not any compendial requirement which any coal tar sample must meet. There is not any specific analytical technique which can detect these variations in constituents. The disadvantages which are associated with currently used techniques viz. HPLC, GC aggregate the problem. Hence, the development of low cost, highly sensitive analytical method which can detect the minute alterations in the composition of coal tar will be helpful in product control, ensuring uniform safety and efficacy of drug product.
Conclusion
The safety and efficacy of coal tar in mild to moderate psoriasis is well documented.
The reason for this report is to increase the reader’s knowledge on the Alberta Tar Sands, which will allow them to create their own opinions on the situation. It is a very pertinent issue in politics and will have a very large effect on the carbon emissions of Canada. Also, I wanted to further my understanding of the Alberta tar sands and learn the side effects of the tar sands. How the tar sands are different from other oil and energy procurement methods and which method is more energy efficient? Would the construction of the Keystone XL pipeline in the United States be an intelligent way for the US to involve itself in the tar sands? I wanted to answer these questions by knowing the real facts about the tar sands versus what the oil companies are telling the consumers. The ability to assess the entire situation will allow both the reader and I to formulate our own opinions about the tar sands and whether the extraction of oil at the tar sands should continue.
Storm water runoff is the biggest polluter of streams, creeks, rivers and ocean water systems. “Nationwide, storm water is a leading source of water pollution. About thirteen percent of U.S. rivers, eighteen percent of lakes and thirty-two percent of estuaries are classified as impaired by storm water, which means they are rendered unsafe for swimming or fishing. It also contributes to the degradation of many other waterways” (Coefield, 2010, p.1). The improperly disposed coal waste from Duke Energy easily percolates through t...
"The Toll from Coal." Catf.us. Clean Air Task Force, Sept. 2010. Web. 25 Nov. 2013.
Coal is one of the world’s most abundant fossil fuels. Coal was formed during the Carboniferous Period when dead plant material was buried and subjected to high pressure and heat. Coal is classified by moisture content and composition. There are four d...
Coal Combustion Residue, or coal sludge, is the byproduct of burning coal in order to make energy. It is a combination of fly ash, bottom ash, coal slag, and flue gas. According to the watchdog group “sourcewatch.org” the ...
The history of tar sands began with one person; Robert C. Fitzsimmons. Fitzsimmons was born in 1881 on Prince Edward Island. He traveled North America completing real estate deals. While in Alberta, Canada, Fitzsimmons noticed that the ground was secreting an oily matter. After his discovery, Fitzsimmons “met with representatives of the Alcan Oil Company of New York, which had recently acquired a number of leases. Robert bought about 600 acres of adjacent leases and went to work for Alcan”(Robert C. Fitzsimmons, 2010). In 1925, Fitzsimmons received approval for creating his own oil drilling company. This is where the “hot water-extraction method” was created (Robert C. Fitzsimmons, 2010). This method uses two L-shaped wells that are parallel to each other in the ground. Hot steam is injected into
Clean Coal Technologies (CCTs) are defined by the WCI as 'technologies designed to enhance both the efficiency and the environmental acceptability of coal extraction, preparation and use' . These technologies reduce emissions, reduce waste, and increase the amount of energy gained from each ton of coal. There are a wide variety of technologies that are available to improve our coal performance. This can be done by: Enhancing of existing options, Deploying of Advanced Technologies, Exploiting Synergies with Renewables, and Development and Commercialization of Next Generation Technologies (“Coal”). Some environmental problems that they will be trying to address are: Particulate matter, trace elements and SOX and NOX, and mercury.
It is made up of sedimentary and organic rock which is composed mainly of carbon, hydrogen and oxygen. Coal is straight from the ground, which also gives many men and women jobs as well as risking their lives working on the unknown underground. There are multiple ways to convert coal into energy we use in an everyday basis. The first step is the first stage of turning coal into electricity, grinding the coal into fine powder and so forth. There are pros that come from the underground such as creating over four hundred thousand volts. As of today they are growing in large economies. They say, "the cheaper the better". In this case, using coal, "the cheaper it is, the less your guaranteed". More than 1.1 billion tons are being made as of 2007. An estimated five billion people work in China 's coal mining industry. As many as 20,000 miners die in accidents each year. Yes, they do give plenty of people the opportunity of some sort of work with good pay, but it has its downfall as well such as deaths, that are pretty unexplainable. The number one con that coal causes, has to be pollution. Pollution can start from anything like throwing a water bottle after a long practice, or chemically, like a cigarette you throw out of your car. Pollution is already exposed by the refineries, factories and diesel vehicles. Pollution is the start of what changes the color and texture of our land and ocean. The coal companies use water to create the steam in the boiler taking out water from a lake, after they are finished with the water from the boiler some toxins get in the water and released into our oceans and seas. Plus, the burning of coal which is called ash, that we humans inhale even though we might not see it. Think of it as a dark, smoky layer in the bubble called an atmosphere, and we are stuck standing in the middle. Some coal mining companies are getting a bargain on federal land and skirting export royalties,
...d of in liquid form at large surface impoundments and in solid form at landfills. When burned it releases toxins into the air causing air pollution. When spilled it can release arsenic, lead and mercury into local drinking water systems contaminating water and causing deformities in water life. On the other hand, some see it as a valuable resource for constructing buildings and saving taxpayer’s money. However way coal ash may be viewed, there is evidence that serious health and environmental effects are a result of leac. There have been Overall, coal ash can present major health and environmental problems for the present and future if regulation is not established. Coal ash contains many harmful toxins that can negatively affect residents that live near coal ash disposal sites. These effects can result in cancer, cardiovascular disease, diabetes, and respiratory.
There are three main types of coal. These types are: bituminous, lignite, and anthracite. Anthracite coal is considered to be the most valuable, as it contains the most carbon. More carbon within the coal means that it contains a higher energy content. (Energy Quest) Coal is mostly used to provide energy to plant that manufacture electricity, steel, and cement.
converted into ethanol biochemically, but is easy to do thermochemically. The optimal biomasses for thermochemical conversions are trees and mill products. These have a high lignin concentration, so these biomass products respond better to the thermochemical method of ethanol production (Theis, 2007). Figure 3 shows the thermochemical process. The first step is drying the plants. Next the plants are burned into synthesis gas, or syngas. The syngas is made of carbon monoxide (CO) and hydrogen (H2). This is called gasification. The gasification produces tar and sulfur, which is not clean and interferes with the making of ethanol. As a result, the syngas is sent to a tar reformer (Nasr, n.d., Theis, 2007). The tar reformer uses enzymes to convert about 97% of the tar into syngas (Theis, 2007). Then, the syngas is cleaned to get purer CO and H2 gasses. Next, the gas is compressed and mixed with a metal catalyst. The catalyst builds the gas back up into ethanol (Nasr, n.d.). There are some drawbacks to the thermochemical process, however. The catalysts used in the tar reformer are very expensive and the tar remains accumulate. Biorefineries could utilize
Coal is formed from remains of vegetation that grew hundreds of millions of years ago. A majority of our coal was formed about 300 million years ago. During this time, most of the earth was covered with steamy swamps. As time passed, the remains of dead plants and trees sank to the bottom of these swamps. These layers of dead plant remains eventually become a dense and soggy substance known as peat. Throughout time, seas and rivers allowed sand, clay, and other mineral deposits to layer upon the peat. The increase of this process eventually caused the substance to form into coal.
Coal has a very negative impact on the environment, one of the main impacts on the environment is the actual process of extracting the coal from the ground. The two ways that coal is mined, underground and surface, both have different effects on the environment. The first way that coal is mined is by digging tunnels and creating mineshafts underground and then removing the coal from th...
All different kinds of secondary products are discussed in these section such as particulate matter (section 2.3.1), Tar compound (section 2.3.2), Sulphur compound (2.2.4). Although not much literature is available, section 2.3.3 briefly introduces the importance of Alkaline, heavy metals and halides compounds as secondary products. It is worth mentioning that secondary products come out from the gasification process concentrations of which in the gas depend on the biomass composition and the technology used.
The sample was subjected to steam distillation as illustrated in Figure 1. A total of 50ml of distillate was collected while recording the temperature for every 5.0 ml of distillate. The distillate was transferred into a 250ml Erlenmeyer flask and 3.0 g of NaCl was added. The flask was cooled and the content was transferred into a 250-ml separatory funnel. Then 25.0ml of hexane was added and the mixture was shaken for 5 minutes with occasional venting. The aqueous layer was discarded and the organic layer was left inside. About 25.0ml of 10% NaOH was then added and the mixture was shaken as before. The aqueous layer was collected and then cooled in an ice bath. It was then acidified with enough 6.00 M HCl while the pH is being monitored with red litmus paper. Another 25.0 ml of hexane was added and the mixture was shaken as before. The hexane extract was saved and a small amount of anhydrous sodium sulfate was added. The mixture was then swirled for a couple of minutes then filtered. A small amount of the final extracted was tested separately with 1% FeCl3 and Bayer’s reagent.