The solution for the resistance to oxidation of p-toluic acid was solved by the discovery of bromide-controlled air oxidation in 1955 that was led to the implementation of AMOCO process [28-31]. In AMOCO process, the oxidation of para-xylene was conducted using a combination of three ions as a homogeneous catalyst which is cobalt, manganese and bromide ions. Acetic acid and oxygen/air were used as solvent and oxidant, respectively [32]. The common bromide ion sources are hydrobromic acid (HBr) and sodium bromide (NaBr). The oxidation operated at 175-225°C and 15-30 bar of oxygen. The terephthalic acid formed mostly in the form of solid due to the low solubility of terephthalic acid in the acetic acid. AMOCO process successfully gives a promising reaction yield, since more than 98% of para-xylene reacted, while terephthalic acid selectivity yield was about 95% in the reaction time of 8-24 hours (Scheme 3).
Scheme 3. AMOCO commercial process of para-xylene oxidation to terephthalic acid [32].
As shown in Scheme 2, the consecutive oxidations of methyl group take place for p-toluic acid and 4-CBA. In order to gain terephthalic acid as the end product, the purification from impurities including 4-CBA content in crude terephthalic acid must be conducted. In purification process, the crude terephthalic acid (a solid terephthalic acid that has been undergoing centrifugation and drying) will be dissolved in hot water to reduced 4-CBA to p-toluic acid. This reduction process is through catalytic hydrogenation on palladium catalyst. Then, the purified terephthalic acid is obtained [33]. Apart AMOCO process, the other catalytic process to produce terephthalic acid by direct oxidation was widely st...
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...terephthalic acid solubility in water increased linearly proportional with temperature. This situation happens due to the low dielectric constant nature in supercritical water, making it as a good solvent for non-polar substance like para-xylene. Therefore, it can be concluded that the reaction and yield of the reaction could be adjusted by the modification of reaction temperature. As shown in Table 1, the application of sub and supercritical water, could give a greater yield in terephthalic acid, >50%. However, the industrial implementation always demanding the practical application in terms of energy, nature of chemical and operation cost. Even sub and supercrical water could produce high amount of terephthalic acid, but the temperature and pressure applied in this application was far from safe and commercially practical.
Works Cited
Universiti Malaysia PAhang
In a small reaction tube, the tetraphenylcyclopentadienone (0.110 g, 0.28 mmol) was added into the dimethyl acetylene dicarboxylate (0.1 mL) and nitrobenzene (1 mL) along with a boiling stick. The color of the mixed solution was purple. The solution was then heated to reflux until it turned into a tan color. After the color change has occurred, ethanol (3 mL) was stirred into the small reaction tube. After that, the small reaction tube was placed in an ice bath until the solid was formed at the bottom of the tube. Then, the solution with the precipitate was filtered through vacuum filtration and washed with ethanol. The precipitate then was dried and weighed. The final product was dimethyl tertraphenylpthalate (0.086 g, 0.172mmol, 61.42%).
Z Qin et al modified ammonium polyphosphate (APP) and compared the effect of modification on flame retardant properties of polypropylene along with dipentaerythritol (DPER). The incorporation of modified ammonium polyphosphate (IMAPP) with dipentaerythritol (DPER) at 25 % loading produced LOI 32% with V-0 rating while unmodified APP had LOI 26% and V-1 rating. IMAPP also significantly decreased the PHRR and THR and contributed to the formation of compact intumescent
In this experiment, four elimination reactions were compared and contrasted under acidic (H2SO4) and basic (KOC(CO3)3) conditions. The acid-catalyzed dehydration was done on 2-butanol and 1-butanol; a 2ᵒ and 1ᵒ alcohol, respectively. The base-induced dehydrobromination was performed on 2-bromobutane and 1-bromobutane; isomeric halides. The stereochemistry and regiochemistry of the four reactions were analyzed by gas chromatography (GC) to determine product distribution (assuming that the amount of each product in the gas mixture is proportional to the area under its complementary GC peak. The three butene products have been verified that they elute in the following order: 1-butene, trans-2-butene, and cis-2-butene.
As an emergency response coordinator for a refinery it is vital to understand what hazards are associated with the products found in a crude oil refinery. Routine and non-routine maintenance will need to be done in order to maintain a working and operating oil refinery. This can create complicated situations or scenarios, because numerous contractors may be brought in for different repairs. This can lead to accidents in some cases because of the wide range of things going on in the refinery. Training and communication will be vital for a safe work environment with multiple entities working. Documentation of the training will also be crucial.
Perchloroethylene (PCE), along with Trichloroethylene (TCE), are the products of the chlorination of Ethylene Dichloride (EDC). This process involves the reaction of EDC with chlorine, where its products undergo further distillation and purification to produce TCE and PCE fit for consumerism trade. The stoichiometry of the given process reaction indicates which is the greater desired product, i.e. either PCE or TCE. The reaction takes place at a temperature of 400 – 450 degrees Celsius and a pressure of 1 atmosphere.
Traditionally cyanide was used as a catalyst in this reaction since Von Liebig first discovered it in his research with almond oil. However, cyanide is very poisonous and harmful to health. More recently it was discovered that Vitamin B1, a coenzyme by the name of thiamine hydrochloride may be used to catalyze the benzoin condensation, which is preferable to using cyanide. This experiment will test whether thiamine can effectively catalyze the reaction (2).
The synthesis of .525 g of para-methoxyacetophenone and .49 g of para-chlorobenzaldehyde using 95% ethanol and catalytic aqueous sodium hydroxide yielded .587 g (61.7% yield) of chalcone 1. The product of chalcone 1 was then confirmed through several different tests. Testing with TLC showed that the product contained a pure substance with only one dot present. The melting point was tested and showed similar characteristics to that of the literature melting points2. The 1H-NMR was analyzed and the key characteristics of the integration values and chemical shifts were comparable to that of the desired chalcone 1 product. Infrared spectroscopy (IR) supported the claim due to the fact that the product’s wavelengths displayed peaks representing characteristics found in the chalcone 1 product. Mass spectrometry was used to confirm the presence of chlorine in our product and to analyze the cation fragments and compare to potential structures. Lastly, this experiment implemented the green chemistry concepts of using safer solvents and a high atom economy while aiming to achieve a high yield product.
The purpose and goal of this experiment is to use the knowledge of substitution reactions and laboratory techniques to synthesize (2-bromoethyl) benzene from 2-phenylethanol; furthermore, to determination if the synthesis is successful, the methods of thin layer chromatography (TLC), the theorized use of gas chromatography along with a mass spectrometer (GC-MS) and flame ionization detector (GC-FID), as well as infrared (IR) spectroscopy will all have their application in this experiment. The hypothesis of this experiment is that if the synthesis is done correctly and is successful, on the TLC, the expected synthesized (2-bromoethyl) benzene in lane 1 should match that of the standard (2-bromoethyl) benzene in lane 2 but may also contain some impurities, somewhat
Imagine being accused of doing something horrible, but didn’t do it. Charges could be placed that could cause money, jobs, and belongings to be lost. Recently, something like that happened. There was a crash that involved a truck from the chem supply co. Nobody was hurt, but dangerous chemicals got into Corn on the Cob farm, and Critter Craze Meadow’s creek. The chem company spent 7 hours of their time cleaning up the debris.The State claims that the CHEM company, caused this damage, but the Chem company is innocent. The CHEM company has never been accused of having harmful chemicals and that the chemicals were environmentally friendly. The evidence collected from the scenes proves that the chem company is not guilty. First of all, none of the samples from Corn on the Cob Farm match the samples from the truck, the chemicals in the water were in the creeks long before the crash, and the facility, which has been suspected of dumping chemicals into the waterways, was right next to the crash site.
Petco started out in 1965 as UPCO, a mail-order veterinary supply company in San Diego, California. In 1991, Red Ruff and Blue Mews became the companies official mascots. The Petco Foundation launched the first National Pet Food Bank in 2010. Today, Petco has over 50 years experience in the pet supplies industry, serving pets and owners with over 1400 locations, and online at petco.com.
The most common form of polyethylene is petroleum based or olefins based; as before mentioned polyethylene compounds have a wide commercial applicability and are made from non-renewable resources (Harding, Dennis, von Blottnitz, Harrison, & S.T.L., 2007). Its manufacturing processes are regarded as energy intensive and release significant amount of CO2 and heat into the atmosphere (Broderick, 2008). Next a little more detailed description of polyethylene’s production processes will be presented, with a focus on the way the material inputs are extracted and synthesized.
After several years shopping at Petco, I have decided to stop shopping for four main reasons:
"The History of Plant Incidents at Formosa Plastics and Past Safety Violations." Industrial Injury Attorneys. http://www.industrialinjuryattorney.com/Industrial-Accident-Blog/2013/May/The-History-of-Plant-Incidents-at-Formosa-Plasti.aspx (accessed April 3, 2014).
In the oxidation of borneol to camphor, a hydrogen is removed from the carbon attached to the hydroxy group. In order for the all the atoms to have octets, the charged carbon forms double bonds with the oxygen atoms. The product produced is camphor.
Commercial Recuperation Essentially what Hebdige is saying with his statement is that eventually a subcultures generic trademarks will cross over into the mainstream. This will in tern render the original intentions of subversion diluted pastiches of there former representations. The validity of this statement is interesting in two ways. Firstly are subcultures subversive qualities diluted through popularisation?