scholarly journals Effect of Temperature on Gas and Liquid Products Distribution in Thermal Cracking of Nigerian Bitumen

2021 ◽  
Vol 22 (2) ◽  
pp. 7-16
Author(s):  
ABIMBOLA GEORGE OLAREMU ◽  
Ezekiel Oluyemi ODEBUNMI ◽  
Jim A ANDERSON
Keyword(s):  
Thermal Cracking ◽  
Product Distribution ◽  
Reaction Scheme ◽  
Effect Of Temperature ◽  
Gas Chromatography Mass Spectrometry ◽  
Reaction Products ◽  
Sulphur Compounds ◽  
Oil Reserves ◽  
Liquid Products ◽  
Cracking Reaction

The increasing population growth resulting in the tremendous increase in consumption of fuels, energy, and petrochemical products and coupled with the depletion in conventional crude oil reserves and production make it imperative for Nigeria to explore her bitumen reserves so as to meet her energy and petrochemicals needs. Samples of Agbabu bitumen were subjected to thermal cracking in a tubular steel reactor operated at 10 bar pressure to investigate the effect of temperature on the cracking reaction. The gas produced was analyzed in a Gas Chromatograph while the liquid products were subjected to Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Heptane was the dominant gas produced in bitumen cracking at all temperatures and the reaction products show a distribution of lighter hydrocarbons most of which are in the gasoline range. The product distribution of bitumen conversion depends strongly on the cracking temperature and the oil produced contains the valuable liquid fractions. The products of thermal cracking of bitumen can be classified into the following groups; alkanes, alkenes, amines, aromatics, alkanoic acids, alkanols, esters, ethers, ketones, sulphur compounds, and nitrogen compounds. The activation energies of the products formed were determined. The LNG produced all have unusually low values activation energy (hence easily converted) pointing to the high quality of Agbabu crude      The conversion process was affected by the reaction time and suggests that the transformation of bitumen into smaller fractions follows a definite reaction scheme in which the heavy oil transformed to lower fractions and was subsequently converted to smaller liquid fractions and gases.

Kinetics and modelling of heptane steam-cracking

2014 ◽  
Vol 68 (12) ◽  
Author(s):  
Natália Olahová ◽  
Martin Bajus ◽  
Elena Hájeková ◽  
Lukáš Šugár ◽  
Jozef Markoš
Keyword(s):  
Flow Reactor ◽  
Frequency Factor ◽  
Product Distribution ◽  
Reaction Scheme ◽  
Reaction Products ◽  
Primary Products ◽  
Molecular Reaction ◽  
Secondary Reactions ◽  
Steam Cracking ◽  
Good Agreement

AbstractThe kinetics and product distribution during the cracking of heptane in the presence of steam were investigated. The experiments were performed in a flow reactor under atmospheric pressure in a temperature range of 680–760°C with a mass ratio of steam to heptane of 3: 1. The overall decomposition of heptane is represented by a first-order reaction with activation energy of 249.1 kJ mol−1 and a frequency factor of 3.13 × 1013 s−1. The reaction products were analysed using gas chromatography, the main product being ethylene. The molecular reaction scheme, which consists of a primary reaction and 24 secondary reactions between primary products, was used for modelling the experimental product yields. The yields of ethylene and hydrogen were in good agreement; however the experimental yields of propylene were higher than the predicted yields.

scholarly journals Investigation of thermal and catalytic degradation of polystyrene waste into styrene monomer over natural volcanic tuff and Florisil catalysts

2013 ◽  
Vol 11 (5) ◽  
pp. 725-735 ◽  
Author(s):  
Miuţa Filip ◽  
Aurelia Pop ◽  
Ioana Perhaiţa ◽  
Mărioara Moldovan ◽  
Roxana Truşcă
Keyword(s):  
Textural Properties ◽  
Product Distribution ◽  
Catalytic Degradation ◽  
Gas Chromatography Mass Spectrometry ◽  
Conversion Degree ◽  
Infrared Spectrometry ◽  
Volcanic Tuff ◽  
Styrene Monomer ◽  
Liquid Products ◽  
Polystyrene Waste

AbstractThermal and catalytic degradation of polystyrene waste over two different samples of natural volcanic tuff catalyst comparative with Florisil catalyst has been carried out in order to establish the conversion degree into styrene monomer. The polystyrene waste (PS) was subjected to a thermal degradation process in the range of 380–500°C in presence of studied catalysts in a ratio of 1/10 in mass, catalyst/PS. The catalysts were characterized by N2 adsorption-desorption isotherms (BET), Scanning Electron Microscopy (SEM) and Fourier-transform infrared spectrometry (FTIR). Influences of temperature and type of catalysts on the yields and on the distribution of end-products obtained by thermal and catalytic degradation of polystyrene waste have been studied. The maximum yields of liquid products were obtained at 460°C degradation temperature and were calculated between 83.45% and 90.11%. The liquid products were characterized by gas chromatography mass spectrometry (GC-MS) and FTIR analytical techniques. The GC-MS results showed that the liquid products contained styrene monomer up to 55.62%. The FTIR spectra of liquid products indicated the specific vibration bands of the functional groups of compounds of liquid products. The amounts of styrene monomer obtained were influenced by structural and textural properties of studied catalyst and the contribution on product distribution is discussed.

Practical Method of Gravimetric Tar Analysis That Takes into Account a Thermal Cracking Reaction Scheme

2009 ◽  
Vol 23 (12) ◽  
pp. 6156-6162 ◽  
Author(s):  
Tomoaki Namioka ◽  
Young-il Son ◽  
Masayuki Sato ◽  
Kunio Yoshikawa
Keyword(s):  
Thermal Cracking ◽  
Practical Method ◽  
Reaction Scheme ◽  
Cracking Reaction

scholarly journals Effect of Zn/ZSM-5 and FePO4Catalysts on Cellulose Pyrolysis

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Haian Xia ◽  
Xiaopei Yan ◽  
Siquan Xu ◽  
Li Yang ◽  
Yuejie Ge ◽  
...  
Keyword(s):  
Lewis Acid ◽  
Value Added ◽  
Product Distribution ◽  
Acid Sites ◽  
Gas Chromatography Mass Spectrometry ◽  
Lewis Acid Sites ◽  
Liquid Products ◽  
Temperature Programmed ◽  
Xrd Techniques ◽  
Brønsted And Lewis Acid

A series of Zn/ZSM-5 catalysts with different Zn contents and FePO4were used to pyrolyze cellulose to produce value added chemicals. The nature of these catalysts was characterized by ammonia-temperature programmed desorption (NH3-TPD), IR spectroscopy of pyridine adsorption, and X-ray diffraction (XRD) techniques. Noncatalytic and catalytic pyrolytic behaviors of cellulose were studied by thermogravimetric (TG) technique. The pyrolytic liquid products, that is, the biooils, were analyzed by gas chromatography-mass spectrometry (GC-MS). The major components of the biooils are anhydrosugars such as levoglucosan (LGA), 1,6-anhydro-β-D-glucofuranose (AGF), levoglucosenone (LGO, 1,6-anhydro-3,4-dideoxy-β-D-pyranosen-2-one), and 1,4:3,6-dianhydro-α-D-glucopyranose (DGP), as well as furan derivatives, alcohols, and so forth. Zn/ZSM-5 samples with Brønsted and Lewis acid sites and the FePO4catalyst with Lewis acid sites were found to have a significant effect on the pyrolytic behaviors of cellulose and product distribution. These results show that Brønsted and Lewis acid sites modified remarkably components of the biooil, which could promote the production of furan compounds and LGO. On the basis of the findings, a model was proposed to describe the pyrolysis pathways of cellulose catalyzed by the solid acid catalysts.

scholarly journals Torrefaction of Agricultural Residues: Effect of Temperature and Residence Time on the Process Products Properties

2020 ◽  
Vol 142 (7) ◽  
Author(s):  
Katarzyna Jagodzińska ◽  
Michał Czerep ◽  
Edyta Kudlek ◽  
Mateusz Wnukowski ◽  
Marek Pronobis ◽  
...  
Keyword(s):  
High Performance ◽  
Calorific Value ◽  
Barley Straw ◽  
Effect Of Temperature ◽  
Gas Chromatography Mass Spectrometry ◽  
Toxicity Tests ◽  
Main Compound ◽  
Flame Ionization ◽  
Polycyclic Aromatic ◽  
The Impact

Abstract To date, few studies on the potential utilization of agricultural residue torrefaction products have been performed. Thus, torrefaction product characterization aimed at its potential utilization was performed. Wheat–barley straw pellets and wheat–rye chaff were used in the study. The impact of the torrefaction temperature (280–320 °C) on polycyclic aromatic hydrocarbons (PAHs) content in the biochar and noncondensable gas (noncondensables) composition was investigated. The impact of the torrefaction time (30–75 min) on the composition of the condensable volatiles (condensables) and their toxicity were also studied. The torrefaction process was performed in a batch-scale reactor. The PAH contents were measured using high-performance liquid chromatography (HPLC), and the noncondensables composition was measured online using a gas analyzer and then gas chromatograph with flame ionization detector (GC-FID). The condensables composition and main compound quantification were determined and quantified using gas chromatography–mass spectrometry (GC/MS). Three toxicity tests, for saltwater bacteria (Microtox® bioassay), freshwater crustaceans (Daphtoxkit F magna®), and vascular plants (Lemna sp. growth inhibition test), were performed for the condensables. The PAHs content in the biochar, regardless of the torrefaction temperature, allows them to be used in agriculture. The produced torgas shall be co-combusted with full-caloric fuel because of its low calorific value. Toxic compounds (furans and phenols) were identified in the condensable samples, and regardless of the processing time, the condensables were classified as highly toxic. Therefore, they can be used either as pesticides or as an anaerobic digestion substrate after their detoxification.

scholarly journals Valuable Chemicals Derived from Pyrolysis Liquid Products of Spirulina platensis Residue

2019 ◽  
Vol 19 (3) ◽  
pp. 703 ◽  
Author(s):  
Siti Jamilatun ◽  
Budhijanto Budhijanto ◽  
Rochmadi Rochmadi ◽  
Avido Yuliestyan ◽  
Arief Budiman
Keyword(s):  
Polyaromatic Hydrocarbons ◽  
Food Additives ◽  
Fixed Bed ◽  
Liquid Product ◽  
Fixed Bed Reactor ◽  
Water Phase ◽  
Gas Chromatography Mass Spectrometry ◽  
Human Needs ◽  
Liquid Products ◽  
Interesting Alternative

With a motto of preserving nature, the use of renewable resources for the fulfillment of human needs has been seen echoing these days. In response, microalgae, a water-living microorganism, is perceived as an interesting alternative due to its easy-to-cultivate nature. One of the microalgae, which possess the potential for being the future source of energy, food, and health, is Spirulina plantesis. Aiming to identify valuable chemicals possibly derived from it, catalytic and non-catalytic pyrolysis process of the residue of S. plantesis microalgae has been firstly carried out in a fixed-bed reactor over the various temperature of 300, 400, 500, 550 and 600 °C. The resulting vapor was condensed so that the liquid product consisting of the top product (oil phase) and the bottom product (water phase) can be separated. The composition of each product was then analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). In the oil phase yield, the increase of aliphatic and polyaromatic hydrocarbons (PAHs) and the decrease of the oxygenated have been observed along with the increase of pyrolysis temperature, which might be useful for fuel application. Interestingly, their water phase composition also presents some potential chemicals, able to be used as antioxidants, vitamins and food additives.

scholarly journals THE PARAFFIN CRACKING REACTION WITH NiMo/ACTIVE NATURAL ZEOLITE CATALYST: THE EFFECT TEMPERATURE ON CATALYTIC ACTIVITYTHE PARAFFIN CRACKING REACTION WITH NiMo/ACTIVE NATURAL ZEOLITE CATALYST: THE EFFECT TEMPERATURE ON CATALYTIC ACTIVITY

2016 ◽  
Vol 11 (2) ◽  
pp. 111 ◽  
Author(s):  
Khoirina Dwi Nugrahaningtyas ◽  
Eko Cahyono ◽  
Dian Maruto Widjonarko
Keyword(s):  
Gas Chromatography ◽  
Natural Zeolite ◽  
Zeolite Catalyst ◽  
Catalyst Activity ◽  
Gas Chromatography Mass Spectrometry ◽  
Hydrogen Flow ◽  
Catalyst Temperature ◽  
Cracking Reaction ◽  
Active Natural ◽  
Cracking Products

This research deals with the study of the paraffin cracking reaction with termal reaction, active natural zeolite (ZAA) and NiMo / active natural zeolite (ZAA) catalyst. Temperature variation was done in order to study the optimum temperature of paraffin cracking reactions. Paraffin cracking reaction carried out at temperatures of 200 - 400 °C and a hydrogen flow rate of 30 mL / min. Cracking products obtained, and then analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry(GCMS). Catalyst activity (%) was defined as the amount of lighter fractions/the amount of feed (paraffin) (%). The results showed that the catalyst NiMo/ZAA has the highest activity (31.33 %) at the cracking reaction temperature of 300 ºC

5-Nitroimidazoles. II: Unexpected reactivity of ronidazole and dimetridazole with thiols

1993 ◽  
Vol 71 (9) ◽  
pp. 1349-1352 ◽  
Author(s):  
Michel Girard ◽  
François Clairmont ◽  
Aspi Maneckjee ◽  
Nicole Mousseau ◽  
Brian A. Dawson ◽  
...  
Keyword(s):  
Biological Systems ◽  
Product Distribution ◽  
Veterinary Drugs ◽  
Spectroscopic Techniques ◽  
Reaction Products ◽  
Nucleophilic Reaction ◽  
Alternative Path ◽  
Rate Of Reaction ◽  
Bound Residues ◽  
Aqueous Conditions

Ronidazole and dimetridazole, two important veterinary drugs, were found to react readily in the presence of cysteine, under neutral aqueous conditions, leading to the formation of 5-S-cysteinyl-1-methylimidazole-2-methanol carbamate and 5-S-cysteinyl-1,2-dimethylimidazole respectively through nitro displacement. The reaction products were identified by spectroscopic techniques. The rate of reaction was accelerated by increasing the pH of the medium and was accompanied by a slight change in the product distribution. The reaction was also observed, albeit at a slower rate than that of cysteine, with glutathione, another ubiquitous thiol substrate found in biological systems. While this type of nucleophilic reaction has previously been observed for suitably substituted nitrobenzene derivatives, to the best of our knowledge its occurrence with nitro-heteroaromatics has never been reported. The ready reaction of the parent nitro drugs under such mild aqueous conditions suggests that this may be an alternative path for the formation of nonextractable bound residues in tissues.

Chemical Recycling of Epoxide-Anhydride Hardened Networks Using Near-Critical Water

2013 ◽  
Vol 658 ◽  
pp. 153-157 ◽  
Author(s):  
Yu Yan Liu ◽  
Song Quan Wu ◽  
Li Li ◽  
Yu Ting Liu ◽  
Guo Hua Shan
Keyword(s):  
Epoxy Resin ◽  
Degradation Rate ◽  
Diglycidyl Ether ◽  
Gas Chromatography Mass Spectrometry ◽  
Chemical Recycling ◽  
Reaction Products ◽  
Degradation Behaviour ◽  
Bisphenol A Diglycidyl Ether ◽  
Stainless Steel Reactor ◽  
Degradation Reaction

The degradation behaviour of an anhydride-cured bisphenol A diglycidyl ether (DGEBA) epoxy resin in near-critical water was studied in this paper. The experiments were performed in a stainless steel reactor (100ml) without stirring. Epoxy resin could be decomposed successfully at 270°C for 30 min. The degradation rate of epoxy resin increased with an increase in reaction temperature and reaction pressure. The degradation reaction products were characterized by gas chromatography-mass spectrometry (GC-MS). The degradation reaction was associated with the scission of ester and ether bonds which further destabilizes the epoxy network.

The effect of white or grey PVC pipe and its joint solvents (primer and cement) on odour problems in drinking water distribution systems

2007 ◽  
Vol 55 (5) ◽  
pp. 169-176 ◽  
Author(s):  
K.E. Wiesenthal ◽  
I.H. Suffet
Keyword(s):  
Drinking Water ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems ◽  
Gas Chromatography Mass Spectrometry ◽  
Reaction Products ◽  
Drinking Water Distribution Systems ◽  
Gc Analysis ◽  
Drinking Water Distribution ◽  
Pvc Pipe

A study of the production of odour-causing compounds was conducted from the leaching of polyvinylchloride (PVC) pipe and its joints, primer and cement, into drinking water distribution systems. Flavour Profile Analysis (FPA), closed-loop stripping analysis – gas chromatography/mass spectrometry (CLSA-GC/MS) and sensory-GC analysis of white or grey PVC alone found no odour-causing compounds produced during the leaching experiments. FPA analysis of the PVC's primer and cement leached alone and/or when applied to grey or white PVC pipes produced a glue/varnish odour. A sweet/phenolic odour replaced the glue/varnish odour after the leached media were diluted with Milli-Q water to threshold odour intensity. Three compounds were responsible for the sweet/phenolic odour and were observed by sensory-GC analysis. The leaching study of the PVC pipe with its joint solvents (primer and cement) concluded that the original solvent compounds, and their reaction products that formed during the bonding process on the PVC pipe, were a primary source of the glue/varnish odour. The original compounds of the PVC primer and cement were not detected by CLSA-GC/MS, due to their high volatility during the CLSA extraction method and/or these compounds appeared in a solvent peak of the GC/MS analysis. However, the original primer and cement chemicals (acetone, tetrahydrofuran, methyl ethyl ketone, and cyclohexanone) had a glue/varnish odour. A total of nine odorous GC peaks were produced as reaction products from leaching of primer in water and white or grey PVC pipe with primer and cement, and white or grey PVC with primer only. None of these compounds were among the chemical ingredients in the original primer or cement. Four GC peaks with a sweet/phenolic odour were present due to the reaction products of the cement leached with white or grey PVC. None of these compounds were positively identified.

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