This section discusses the alkanolamines technologies in terms of solvents development. Triethanolamine (TEA) was the first amine commercially used for gas sweetening in the 1930’s due to its selectivity toward H2S over CO2 at low pressures. However, due to the stringent fuel gas specifications, TEA was replaced by new amines due to its inability to remove H2S and CO2 to meet the specifications. Monoethanolamine (MEA) is the earliest and widely used amine for sweetening sour gas due to its selectivity towards the H2S and CO2 [ ]. However, it has a high vapor pressure, results in high solvent losses. MEA forms non-regenerative (degradation) compounds with CO2 and COS; hence it requires “Reclaimer” to regain the solvent gas absorption efficiency. …show more content…
However, filter system is required to remove the HSAS and particulates from the lean amine system, which will cause foaming in the scrubber columns. In addition to liquid solvents, the solid amine phase solvents are emerging uptrend. Methyldiethanolamine (MDEA) reacts more slowly with CO2 compared to H2S than the previously described amines [ ]. It formed a slightly different salt with CO2 compared to those of the other amines. The difference in the rates of reaction against H2S and CO2 has given MDEA a desirable feature over other amines, especially highly selective towards H2S compared to CO2. Moreover, MDEA is also less corrosive compared to the MEA and DEA. Diisopropanolamine (DIPA) is a secondary amine, predominantly used in Shell SulfinolTM process [ ]. This process uses combination of a chemical solvent, DIPA or MDEA, and a physical solvent, sulfolane. The Sulfinol solution comprises of DIPA and Sulfolane in range of 35 to 45% respectively and the remaining will be water in the solution. Due to the low quantity of water, the regeneration and circulation energy is smaller compared to other amine process and make this process economically attractive for treating gases with a high partial pressure …show more content…
[ ] had done a simulation study in Aspen Plus to optimize the Sulfinol-MTM concentration against the MDEA to improve the absorption and lower energy consumption. For this study, the concentration of sulfolane, MDEA and water were varied and find out the optimum solution which will be effective for the refinery. The sulfolane concentration varied from 41 to 49.5 wt%, MDEA concentration varied from 26.45 to 28.31 wt% and the water quantity varied between 31.6 to 21.4 wt%. Based on the simulation studies, it was observed that for Sarakhs gas refinery would have benefited if the existing MDEA solvent is replaced with Sulfinol-M technologies by means of reduced energy consumption and improved acid gas capture efficiency. However, the paper doesn’t disclose the cost of replacing the existing solvent with new solvent and additional cost benefits due to energy
Alkanes are relatively unreactive. There are only a few types of reactions commonly performed. In this lab, halogenation was performed. In the methane molecule, the
The crude product was washed by taking the reaction product in the separatory funnel and adding 23 mL of deionized H2O. The mixture was shaken and allowed to settle until layers were observable. The top layer was the desired product and approximately 25 mL of aqueous layer was extracted from the separatory funnel. Next, 25 mL of 5% NaHCO3 was added to the separatory funnel in order to neutralize the acid. This mixture was swirled, plugged with the stopper and inverted. Built-up gas was released by turning the stopcock to its opened and closed positions, releasing CO2 by-product. This was done four times in one minute intervals. The solution was allowed to settle until layers were observable. The bottom layer that contained salt, base and water was extracted from the separatory funnel. The crude product was washed again as mentioned previously.
For a greener process, the principles and metrics of green chemistry were applied to the reaction process. A principle of green chemistry can be seen in the use of the safe solvent, ethanol, as opposed to the traditional solvents, carbon tetrachloride or methylene chloride, which are highly toxic. Hydrogen peroxide and hydrobromic acid are utilized to
It was desired to compare a theoretical value of enthalpy of combustion to a literature value. To do this, the theoretical value was calculated using a literature value for the heat of sublimation of naphthalene, the heat of vaporization of water and average bond energies, given in Table 1 of the lab packet.1 Equations (1) and (5) were used to calculate the theoretical enthalpy of combustion of gaseous naphthalene, where n was the number of moles, m was the number of bonds, and ΔH was the average bond energy:
Table 1 summarises the results from the primary data collected. Figure 5 indicates there is a linear relationship between the molecular weight and heats of combustion. Figure 6 compares the heats of combustion of the primary data, the accepted values and values calculated from the bond dissociation energy. Figure 6 compares the heat of combustion values identified by the bond dissociation energy calculations, the accepted values and experimental values when 80g of water is heated by 10°C. The bond dissociation energies do not take into account the hydrogen bonding and the accurate energy required to change the tested alkanol from an aqueous state to a gaseous state. The experiments done to identify the accepted values were conducted
In this experiment, the reduction of 4-tert¬-butylcyclohaxanone was performed using sodium borohydride. To complete this reduction, 0.5010 g of 4-tert¬-butylcyclohaxanone was added to 6.0 mL of methanol and heated until the ketone dissolved completely. Next, 0.0510 g of sodium borohydride was added to the solution. At this time, bubbles formed and an exothermic reaction took place. After the solution was stirred for 20 minutes, 2 mL of sulfuric acid was added to the flask. The solution became white and cloudy, and more bubbles formed. Immediately after the acid was added, 5 mL of water was also put into the reaction flask. The solution was stirred for 10 minutes. During this time, a white solid formed. After this, the solution was
For this experiment, a dehydrobromination was performed on a meso-stilbene dibromide to form an alkyne. The meso-dibromostilbene was converted into diphenylacetylene, an alkyne, through two E2 elimination reactions. The dibromostilbene reacted with a strong base, potassium hydroxide, at a very high temperature. The hydroxide, from KOH, deprotonated one of the aliphatic hydrogen atoms or protons which formed an alkene and broke one of the C-Br bonds releasing the bromine. This process does not take much energy to remove one of the H-Br. This process was completed twice, and the second C-Br bond was broken, and an alkyne formed. This process was more difficult due to the rotation needed to perform the initial elimination. The elevated temperature
In the extraction of certain compounds, solubility plays an important factor in how the procedure is performed. The identification of which solvent is best for the substance is crucial. The relation of polarity between the solute and solvent is determined at a molecular level. The relationship between the solvent and solute needed shared similar characteristics. Polar solutes are dissolved in polar solvents while nonpolar solutes are dissolved in nonpolar solvents. From a chemical level, molecules are attracted to other similar molecules closest to their properties. Polar molecules are only attracted to polar molecules in both the solute and the solvent, and the same goes for nonpolar molecules. This explanation
The goal of this experiment was to synthesize an alkene (4-methylcyclohexene) from an alcohol (4-methylcyclohexanol) by dehydration. The reaction, consist of 4-methylcyclohexanol, phosphoric acid, and sulfuric acid, was refluxed at a given time frame. The product was isolated by distillation and purified by adding sodium chloride to help the extraction. The final product had a 125% yield and was characterized by the IR spectroscopy and chemical reaction. The alkene resulted in a colorless liquid after adding molecular bromine dissolved in dichloromethane.
The purpose of this study was to conduct a bromination reaction to manufacture ethyl (2S,3R)-2,3-dibromo-3-phenylpropanoate from ethyl trans-cinnamate utilizing hydrogen bromide, hydrogen peroxide, and ethanol. However, due to an error in the mechanism, the reaction was performed under the same equivalent conditions with trans-diphenylethene to yield 1,2-dibromo-1,2-diphenylethane. Subsequently, a debromination reaction was performed to synthesize diphenylacetylene from the product, 1,2-dibromo-1,2-diphenylethane, utilizing potassium hydroxide and ethylene glycol. Both reactions were performed based on the principles of green chemistry: specifically increasing the atom economy, minimizing the syntheses of hazardous chemicals, utilizing safer solvents, preventing pollution and preventing accidents in the process.1 In order to evaluate the purity, each product was analyzed by obtaining the TLC and melting point range and running the samples in the Infrared spectrometer, Gas chromatography mass spectrometer, and Nuclear magnetic resonance spectrometer. Based on the mass of solid product obtained, the percent yield for ethyl (2S,3R)-2,3-dibromo-3-phenylpropanoate, 1,2-dibromo-1,2-diphenylethane and diphenylacetylene were calculated to be %, %, and % respectively.
Purpose: The purpose of this experiment is to synthesize methyl nitrobenzoate from methyl benzoate, concentrated nitric acid, and concentrated sulfuric acid via an
7 screw cap test tubes were labeled as 0µmol/L, 1.5µmol/L, 2.5µmol/L, 3.5µmol/L, 4.5µmol/L, 5.5µmol/L and 6.5µmol/L. Then, 0µL, 75µL, 125µL, 175µL, 225µL, 275µL and 325µL volume of 0.1mM MDA stock solution was orderly added into screw cap test tubes. 2.0mL of 1% TBA was added into screw cap test tubes. Distilled water was added into screw cap test tubes until total volume reached 5.0mL. They were mixed on whirl mixer. Then, they were wormed on a block heater at 100˚c for 30 minutes. After, they were allowed to cool in cold water for 5minutes. 7 centrifuged tubes were labeled as 0µmol/L, 1.5µmol/L, 2.5µmol/L, 3.5µmol/L, 4.5µmol/L, 5.5µmol/L and 6.5µmol/L. Then, the contents were orderly transferred to centrifuge tubes. They were centrifuged
Alfred Lee 01/31/2015 TA: Zhixun Wang Friday 5:00PM Discussion – Experiment 3A: Separation and Identification of Organic Unknowns Unknown #1 Extraction is a separation method that utilizes differences in solubility to separate compounds (1). The purpose of this experiment was to separate three different organic compounds using extraction and then to identify them by using infrared (IR) spectroscopy. An extraction was carried out on a 750-mg solid mixture containing an acidic, neutral, and basic unknown. In part 1 the solid mixture was first dissolved in 10mL of diethyl ether and then two 10-mL portions of 3M NaOH were added in order to isolate the acidic unknown.
The remaining organic layer was washed with sodium bisulfite and brine. The sodium bisulfite was used to wash away MgOH and neutralize the acid. The solution was dried using anhydrous sodium sulfate and heated until the solvent evaporated. Anhydrous sodium sulfate is a drying agent used to remove water from the mixture. The crude mixture was triturated in petroleum ether. Trituration broke down the crude mixture into a desirable compound that remained insoluble, and impurities, which were soluble in the liquid. Therefore, the impurities were filtered out using petroleum ether. This rinsed away the non-polar byproduct,
A way to approach the elimination of carbon monoxide from car exhaust is through the use of organometallic catalysts. Through the use of a catalyst, a reaction can occur at a faster rate and at lower activation energy. Said catalysts serve are of great commercial interest because they essentially convert simple mole-cules into more complex ones.6 Unlike homogeneous catalysts, heterogeneous catalysts are not in the same phase as how the reac-tion is occurring. Because of this, the catalysts are considered to be cheaper and easier to obtain. It is also considered more envi-ronmentally friendly to use.6-7