Liquefied petroleum gas

Liquefied petroleum gas Direct Flame Production of Carbon Nanotubes (CNTs) From Liquefied Petroleum Gas (LPG) Abstract Liquefied petroleum gas (LPG) is a common household fuel used for cooking purpose in India. LPG is very rich in its carbon content because of its specific mixing components of predominantly C3 alkane (Propane C3H8) or C4 alkane (Butane C4H10) which provides a better chance of producing strong and good quality nano products like nanotubes, nanotubes nanowires, nanoparticles etc. In our laboratory a lab scale flame reactor is designed and developed for producing carbon nanotubes using LPG as the carbon source in the presence of air as an oxidant under atmospheric conditions. The design aspects and the best operational conditions of the flame reactor for producing carbon nanotubes are discussed. The nanotubes obtained were purified and were further characterized using SEM, TEM XRD and Raman. KEYWORDS: Carbon Nanotubes (carbon); TEM (Transmission electron microscopy); LPG (alkanes); Raman (Raman spectroscopy); XRD; Flame Synthesis; 1. Introduction Liquified petroleum gas (also called as LPG or Autogas) is a mixture of hydrocarbon gases used as a fuel in heating appliances and vehicles and it is increasingly replacing chlorofluorocarbons as an aerosol propellant and a refrigerant to reduce the damage and degeneration of the ozone layer. LPG is a clean, convenient energy source, which can be stored as a liquid under moderately high pressure and used as a gas in commercial and residential heating applications. It is a common household fuel used for cooking purpose in India, LPG is rich in its carbon content because of its specific mixing components of predominantly C3 alkane (Propane C3H8) or C4 alkane (Butane C4H10) which provides a better chance of producing strong and good quality nano products like nanotubes, nanotubes nanowires, nanoparticles etc. Carbon nanotubes (CNTs) are among the amazing objects that science sometimes creates by accident, without meaning to, but that will likely revolutionize the technological landscape of the century ahead. Our society stands to be significantly influenced and shaped by carbon nanotube applications in every aspect, Carbon nanotubes have been synthesized for a long time as products from the action of a catalyst over the gaseous species originating from the thermal decomposition of hydrocarbons [1]. Since their discovery by Sumio Ijima [2] several ways of preparing them have been explored. The CNTs have been synthesized by various methods e.g. electric arc discharge, laser evaporation and chemical vapor deposition (CVD) [3-5]. Though researchers have been successful to synthesize multi-wall nano tubes they can produce only in milligram to gram quantities in a few hours. However as many potential applications [6-7] of CNTs require kilogram to ton quantities. Apisit Songsasen et al [8] have synthesized CNTs by means of catalytic decomposition of LPG on a Zeolite-supporting Nickel catalyst. Qian et al [9] have reported the formation of CNTs by the decomposition of liquefied petroleum gas (LPG) containing sulfur in the presence of Fe/Mo/Al2O3 catalyst, Since this contains sulfur of a few to several hundred ppm, which can lead to poisoning the catalyst heavily, few reports currently exist on using LPG or natural gas directly for production of carbon nanomaterials, only Prokudina et al [10] has reported CNT synthesis from LPG by CVD method, but till date no information and literature is reported on direct flame synthesis of CNTs by LPG. The main challenge in this field is to develop methods to produce nanotubes on a large scale and at low cost. As Flame synthesis of nano carbons being a continuous flow method, in which flowing gaseous feedstock mixture could produce CNTs in large quantities it has several advantages like easy scale up, partic le size control, dual role of feed gas which serves both as carbon source and fuel, and in-situ generation of catalyst. Hence it is one of the preferred methods for bulk production of not only CNTs but also other nano particles and nano metal oxides. This method is very useful and is of widespread importance. Many groups have investigated gas-phase continuous-flow production of carbon nanomaterials using other hydrocarbons. These studies typically involve passing a mixture of carbon source gas and organo metallic catalyst precursor molecules through a heated furnace. In this paper we report the direct flame synthesis of carbon nanotubes using LPG and air as our gaseous feedstock in a diffusion type burner without any external use of a catalyst and synthesis at optimum process parameters. 2. Experimental The flame reactor (Fig.1) has been indigenously designed to produce carbon nanotubes at our university. The detailed setup and process instrument and diagram (PID) of the reactor (Fig. 2) has been discussed in detail in our previous work [11]. In general our reactor operates under atmospheric pressure. The measured quantity of the LPG and the oxidant reaches the ignition chamber where the partial combustion process occurs where the CNTs are produced. During the process we have observed the dark orange flame color which is perfectly in a spindle form. Along the entire length of the flame, its temperature was recorded using a K-type thermocouple where this temperature can provide some data regarding the growth of nanotubes. The soot thus produced is captured on a glass fiber filter (Axiva GF/A) with the aid of a vacuum pump and the collected soot is scrapped carefully and weighed and later heat treated and oxidized at 550 OC in the presence of air for 60 minutes to remove any traces of amorphous carbon impurities and then the sample is reweighed in order to estimate the loss of amorphous carbon as an impurity then the samples are later characterized by SEM, TEM, XRD and Raman for their quality. The total amount of thermally oxidized and purified sample from the experiment (for 30 minute run) weighed only 0.8g. 3. Results and Discussion3.1 Scanning Electron Microscope Analysis The samples were analyzed using Phillips XL 30 series Scanning Electron Microscope (SEM) from National Center for Compositional Characterization of Materials (NCCCM), Hyderabad. From the Figs (3a 3d) we can see a dense growth of carbon nanotubes at various flow rates with respect to the oxidant to fuel (O/F) ratios between 0.7 1.0 slpm/slpm (standard litre per minute). The average diameter range of the CNTs from the SEM image was found to be around 200 nm -1000 nm and lengths greater than 40 ÃŽ ¼m. 3.2 Transmission Electron Microscope Analysis The TEM (Technai -12, FEI) images (Fig 4a) shows the presence of thickly packed multiwalled CNT with an average diameter of 150 250 nm which is still surrounded by traces of carbonaceous nanoparticle aggregates possibly caused due to the dispersion of the sample in the solvent. This can be assumed that the agglomerated carbon nanoparticles were actually protected by the CNTs during the thermal treatment, as the CNTs might have formed a net like layer covering the nanoparticles and protecting it from the heat and oxidation. Fig 4b shows a thick multi walled CNT around 250 nm in its diameter with lots of traces of agglomerated carbon nanoparticles which can be accounted for the presence of C60 particles which is also in agreement with the XRD analysis in Fig 5. The broken caps of the CNTs also reveal the disorientation and a defective growth of the grapheme layers as seen in the Raman analysis in Fig 6. 3.2 X-ray Diffraction Analysis The XRD (PW1830 Phillips) analysis was carried out using CuKa1 type of radiation with a wavelength (l) of 1.54060 Ã…. XRD (Fig. 5) of nanotubess produced using LPG-air at an O/F ratio of 0.7 slpm/slpm shows a heterogeneous crystallinity in the sample. The raw scan detected three strong peaks. The first peak at 2ÃŽ ¸ angle of 25.77O was found with (110) orientation of atoms along its plane with peak corresponding to graphite with an orthorhombic type of system and an end-centered lattice. The second peak at 2ÃŽ ¸ angle of 43.159O was found with (245) orientation of atoms along its plane with peak corresponding to C60 molecule with a cubic type of system and a primitive lattice. The third peak at 2ÃŽ ¸ angle of 83.475O was found with (112) orientation of atoms along its plane with peak corresponding to graphite with a hexagonal type of system and a primitive type lattice respectively. 3.2 Raman Analysis Raman analysis (Horiba Jobin Yvon T64000, Raman Spectrophotometer) was carried out only on the best sample (Fig.6) which clearly shows the D band G band respectively. The D band (the disorder band is well-known in disordered graphitic materials and located between 1330-1360 cm-1 when it is excited with a visible laser) it is expected to be observed in Multi Walled Nanotubes (MWNT). However when the D band is observed in SWNTs [12], it is assumed to contain defects in the tubes. The G band or (TM- Tangential Mode) [12], corresponds to the stretching mode of the -C-C- bond in the graphite plane [12]. This mode is located near 1580 cm-1. From the figure we can say that the nanotubes are in the slightly disordered graphite phase based on the D band wavelength present at 1349 cm-1. This D band also confirms the presence of amorphous state of carbon in the bulk sample. Based on the G band from the figures, there appears two peaks at 1560 and 1600 cm-1 respectively which proves the presenc e of multi layers of disordered graphene sheets. On analyzing the level of graphitization using the D and G band intensities ratio, we find that the sample is normally well graphitized with small degree of crystallinity and its ID/IG ratio was found to be around 0.939. 4. Conclusions Carbon nanotube (CNT) is a versatile group of applied chemicals with high degree of applications on larger scale in various disciplines. The synthesis, purification and the cost still remains an un-doubted debate around the world hence an economical approach is to be developed in order to produce large amounts of good quality CNTs from an economical and a resourceful fuel. LPG as a general commodity plays a major role since its availability in India is high and it is a very economical source of fuel as well. Here, we were able to successfully synthesize semicrystalline, CNTs from LPG with an average diameter of 100 500 nm using the direct flame synthesis approach. References [1]. Bharat Bhushan, Springer Handbook of Nanotechnology, Springer-Verlag Berlin Heidelberg, New York, 2004, Chap: 3, pp 39 40. [2]. S. Iijima, Nature 354, (1991), 56. [3]. T.W. Ebbesen and P.M. Ajayan, Nature 358, (1992), 220. [4]. T. Guo, P. Nikolaev, A.G. Rinzler, D. Tomanek, D.T. Colbert and R.E. Smalley, J. Phys. Chem. 99, (1995), 10694. [5]. J. Kong, A. M. Cassell and H.J. Dai, Chem.Phys. Lett. 292, (1998), 567. [6]. Zhou X T, Lai H L, Peng H Y, Au F C K, Liao L S, Wang N, Bello I, Lee C S, Lee S T, Chem Phys Lett 318, (2000), 58 62. [7]. Zhou X T, Wang N, Au F C K, Lai H L, Peng H Y, Bello I, Lee C S, Lee S T, Mater. Sci. Eng. A 286 (2000) 119 -124. [8]. Apisit Songsasen and Paranchai Pairgreethaves, the Kasetsart Journal. (Natural. Sciences) Number 3, 35, (2001), 354 359. [9]. W. Qian, H. Yu, F. Wei, Q. Zhang and W.Wang, Carbon 40, Issue 15, (2002), 2968-2970. [10]. N.A. Prokudina, E.R. Shishchenko, O.S. Joo, D.Y. Kim and S.H. Han, Advanced Materials, Vol. 12, Issue 19, (2000), 1444 1447. [11]. Vivek Dhand, J.S Prasad, M. Venkateswara Rao, K. Naga Mahesh, L. Anupama, V. Himabindu, Anjaneyulu Yerramilli, V.S. Raju, A.A. Sukumar Indian Journal of Engg Mat. Sci, 14, (2007), 240-252. [12]. http://www.jobinyvon.com/usadivisions/Raman/applications/Carbon03.pdf

Essay --

Oil is one of the largest components of the American economy. However through the last thirty years America has had to overcome many obstacles in order to secure a steady flow of oil from foreign countries. Since the early 1970s many political leaders have encouraged drilling in the Arctic National Wildlife Refuge (ANWR) to solve America’s problem of securing foreign oil. The people in favor of letting companies drill in the ANWR argue that it would reduce America’s dependence on foreign oil, and not effect the environment. People against oil drilling in the ANWR state that the drilling would do nothing to change America’s dependence on Foreign oil, and will have detrimental effects on one of the world’s largest untouched nature-preserves. In order to secure and stabilize both the Environment and America’s oil supply, America will need to assign a small section of the ANWR for oil drilling, that would not effect the natural ecosystems. One near-sighted proposal to help reduce America’s foreign dependence for oil has been to drill for oil in the ANWR. Currently the United States imports around 60 percent of the oil that its citizens consumes annually and around 20 percent of this oil comes from the Persian Gulf countries, averaging about 2.4 million barrels a day are being imported to the United States (Corsi 11). Each barrel of oil costs around 50$, meaning the United States sends more than 600$ million a day to foreign countries, of which 120$ million goes to the Persian Gulf. Annually the United States spends just under a quarter of a trillion dollars to buy oil. These numbers show that the United States is very dependent on oil from foreign countries, and has had to intervene in foreign entanglements because of it, such a... ...structures (which was not the case in Prudhoe Bay,) there would be other suitable calving areas. The oil fields operated ANWR would also help make the United States less dependent on foreign oil. Although the United States will most likely never be completely independent of oil, the Oil drilled in the ANWR would save the United States millions of dollars a year, from paying foreign countries to sell us oil. If we have a steady domestic oil supply, the United States will not have to focus so much of its attention on foreign issues that are not related to us. Keeping the environment pristine, and having a secure line of oil are big concerns of the United States government. By assigning a small section of the ANWR for oil drilling and setting restrictions on oil infrastructures during calving season would let America succeed in both the economy and the environment.

How is Richard II portrayed in act I? Essay

In Act I of Richard II, Richard is portrayed as powerful, pompous and arrogant, all somewhat contrastingly to his portrayal towards the end of the play. We see even as early as Act I glimpses of Richard’s fatal flaws and the crucial mistakes he makes which determine his dramatic fall. The genre of the play is historic tragedy, so the audience know the main protagonist; in this case Richard; is doomed from the start. So, in Act 1 Shakespeare’s portrayal of him is not only purposeful for his fall, but also hugely ironic, making his descent to †¦Ã¢â‚¬ ¦ even more dramatic. Immediately in Act I, Richard’s power and authoritative presence is apparent. The setting in Windsor Castle is a very formal occasion, as Richard gives Bullingbrook and Mowbray a formal hearing. It is really overblown and grandeur setting for the opening scene and so even before any speech, Richard is perceived as being powerful and omnipotent. On stage Richard, is central and stationed upstage to observe the proceedings. When he descends from his raised platform (which was traditional) and walks downstage to stop the proceedings later in the scene, he travels quite a distance on stage, reinforcing his pivotal place on the stage and in the political picture. These proxemics physically symbolise how Richard was the most powerful, which is extremely ironic as at the end of the play the roles are reversed as Bullingbrook defeats Richard. Richard is then the first character to speak, and refers to Bullingbrook and Mowbray by ‘Henry Hereford’ (I/I/3) and ‘Duke of Norfolk’ (I/I/6), making it seem very occasional and formal, so he appears as the voice of authority and as he is the first character to speak, it again re-emphasizes his ascendency. Alongside the first scene being a hugely occasional event, whereby Richards importance and authority is greatly established, is it written in rhyming couplets; likewise the rest of the play. Richard II is the only one of Shakespeare’s plays not written in prose, which gives it a sense of importance and authority. As the title of the play is Richard II, this then dramatizes how much power Richard initially had and so how much was at stake. As king of England in the 14th Century, Richard along with the majority of his people believed in the Divine Right. As we can see by his use of the royal ‘We’(I/I/24) ‘us’(I/I/24) and ‘our’(I/I/84), by this he is referring to himself and God, which shows Richard’s arrogance and audacity, as he refers to himself with a heightened sense of authority. However, as the Act continues we realise that although Richard is King of England so along with the title comes extraordinary wealth and power, Richard is not all that powerful and authoritative. When he uses the metaphor ‘Rage must be withstood/ Give me this gage. Lions make leopards time’ (I/II/173-4) here he is trying to assert his dominance and gain back control over the hearing as Bullingbrook and Mowbray demand a fight. He is reminding them of his pre-eminence, which makes him seem not only egotistical but shows his lack of control especially following Mowbray’s reply; ‘Yea, but not change his spots’ (I/II/175). His undaunted and scintillating response show is lack of true and honest respect for Richard, aside from formalities. It shows Richard’s lack of intrinsic power if a noble can under-mine him, and feels the need to knowing what the consequences may be. Not only is the whole play written in poetic rhyming couplets, but much of Richard’s speech is written very poetically and Shakespeare uses a lot of colourful and figurative language in his speech. By ‘face to face’ ‘brow to brow’ ‘the accuser and the accused’ Richard is repeatedly using mirroring imagery to re-enforce the idea of the ‘standoff’ coming between Bullingbrook and Mowbray, but also signifies the ultimate standoff between himself and Bullingbrook. However, this repetition creates a racy rhythm making him sound arrogant and pompous. From Richards continuous use of dramatic and poetic language, we can see he is not a man of action; a conclusion which is supported as in Act I Scene I he stands away and watches Bullingbrook and Mowbray fight, he is higher than them, symbolically and physically. Also, by him stopping Bullingbrook and Mowbray’s joule ‘Let them lay by their helmets and their spears/ And both return back to their chairs again’ (I/III/119-20) he looks effeminate and weak. Although he has an extraordinary flair for poetry but this appears to be his fatal flaw, he relies on language and words rather than traditional war and action. This is totally contrasting to Bullingbrook’s characterisation in Act I, he is willing to fight Mowbray till death ‘And as I truly fight, defend me heaven’ (I/III/41), he is a man of action and it is this which ultimately leads to Richard’s fall and defeat. However, this is somewhat ironic as his failing is words, but Shakespeare himself is a man of words and beautifully poetic language, which makes his failing and collapse even more dramatic as it is totally un-expected for his audience. As well as seeing Richard’s dependence on words and poetry we also are also introduced to another of Richards fatal mistakes. In Act 1 Scene 4 we see Richard in a completely new light, when Bushy informs him of Gaunt’s deteriorating health and the fact he is close to death, instead of feeling grief or any malice or despondency his first thought is of his inheritance. His response is cruel and heartless, only focusing on his financial gains from Gaunt’s death, ‘The lining of his coffers shall make coats/ To deck our soldiers for these Irish wars. ’ Gaunt’s inheritance is right-fully his son’s, Bullingbrook, so by taking it Richard is giving Bullingbrook a reason to avenge and try to destroy him. Not only does this make Richard seem brutal and callous, but also narcissistic and gallant as he does not even consider Bullingbrook’s reaction. As Richard believes he is God’s representative on earth, he sees himself as ‘untouchable’ impenetrable, so Bullingbrook’s anger does not matter as he cannot defeat him as he is protected by God- an idea certain to make Richard fall, and clearly apparent to the audience. Overall, Richard’s portrayal changes throughout Act I as his flaws and cracks begin to show. He is shown to be authoritative and powerful initially but we then see him to not be as powerful as he believes himself to be. However, there is no doubt that he is egocentric and contemptuous, apparent through his exaggerated self-opinion.

Analysis Of George Orwells The Green Arrow

The person I chose for this paper is Oliver Queen. He is also known as Green Arrow, and is a character in the DC Comics franchise. Oliver’s alter-ego, Green Arrow, rose to popularity recently with the television show Arrow that premiered on television in 2012. I chose Oliver because he is a fascinating character, and is much more than the millionaire playboy that people only know him as in his universe. Oliver is smart, caring, and has suffered a lot in his life. Based on the diagnosis standards of the DSM-5, my primary diagnosis for Oliver would be posttraumatic stress disorder, with a secondary diagnosis of major depressive disorder. Oliver has a lot to discover about his past and hopefully this will give insight to his character.†¦show more content†¦(â€Å"Lone Gunmen†, 2012) Symptoms Among the symptoms in the DSM-5 for posttraumatic stress disorder, Oliver displays most (if not) all of them. He frequently has flashbacks to his time on the island, which show him in a various situation that is traumatic in nature. Oliver also consistently has nightmares, this symptom being defined by the American Psychological Association (2014) as: â€Å"Recurrent distressing dreams in which the content and/or effect of the dream are related to the traumatic event(s).† Oliver has other characteristics that would support this hypothesis. He tends to avoid any topics that would be discussing his time on Lian Yu, or anything else that would remind him of the traumatic events that have occurred in his life. This would be explained as avoidance or attempting to avoid activities, places, or anything else that reminded one of their trauma (American Psychological Association, 2014). Once returning from the island, Oliver becomes withdrawn from his family and friends and does not se em eager to be around people, displaying the symptom of â€Å"socially withdrawn behavior†. (American Psychological Association, 2014). Oliver’s responses to his trauma have been showing themselves since the first episode, titled â€Å"Pilot† (2012). In this episode, he experiences a nightmare and almost kills his mother when she tries