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DESULPHURIZATION OF LIQUID FUELS BY SELECTIVE ADSORPTION THROUGH MINERAL CLAYS AS ADSORBENTS  [cached]
M SHAKIRULLAH,W AHMAD,I AHMAD,M ISHAQ
Journal of the Chilean Chemical Society , 2012,
Abstract: Different clays collected from local sources, including Kaolinite, Montmorollinte, Palygorskite and Vermiculite have been utilized for the selective adsorption of sulphur compounds prevailing in petroleum products i.e. crude oil, kerosene and diesel oil. The desulphurization activity of the clay was compared with the charcoal, ion exchange resins and with each other. Desulphurization was performed in batch operation at different time intervals i.e 1, 3 and 6 hrs at 40 oC temperature. Out of different adsorbents used, Kaoilinte exhibited the maximum desulphurization yield of 60 %, 76 % and 64 % at 6 hrs adsorption incase of crude oil, kerosene and diesel oil respectively. All the mineral clays adsorbents were characterized by surface area, SEM and EDX analysis. The FT-IR study of the desulphurized fractions revealed that mostly high molecular weight thioles and thiophenic compounds were depleted during adsorption process.
Decomposition of formic acid  [PDF]
Martin Schmei?er,J?rg Schuster
Physics , 2011,
Abstract: Formic acid is known to act as a reduction agent for copper oxide. Its thermal uni-molecular decomposition was studied by means of DFT with special attention to reaction paths and kinetics.
Steel desulphurization with synthetic slag  [cached]
Heput, T.,Ardelean, E.,Socalici, A.,Maksay, S.
Revista de Metalurgia , 2007,
Abstract: Generally speaking, sulphur is considered a harmful element for steel quality, reason why all the technological steps are being taken in order to eliminate it from the metal bath. This paper deals with the influence of the chemical composition, on the slag quantity and of the bath stirring condition upon the desulphurization process in the casting ladle by treatment with synthetic slag. The experiments were made at an open-hearth plant with the steel tapping in two ladles (the desulphurization was made with synthetic slag at one ladle while the other one was considered standard) and at the electric steel plant and for the synthetic slag formation a mix was used, made, according to several receipts, of: lime (50-75%), fluorine (0-17%), bauxite (0-32%) and aluminous slag (8-22%). The data were processed in the calculation programs EXCEL and MATLAB, which resulted in a series of correlations between the desulphurization degree and the chemical composition of the slag, respectively the slag quantity both for the charges bubbled with Argon and the unbubbled ones. En general, el azufre es considerado un elemento nocivo para la calidad del acero y, por eso, en la práctica, se toman todas las medidas de orden tecnológico para su eliminación del ba o metálico. En este trabajo se analiza la influencia de la composición química, de la cantidad de escoria y del estado de agitación del ba o sobre el proceso de desulfuración en la cuchara para fundir por tratamiento con escoria sintética. Los experimentos se han realizado en una acería evacuando el acero en dos ollas (en una cuchara se efectuó la desulfuración con escoria sintética y a la otra se consideró como patrón) y en un acería eléctrica y para la formación de la escoria sintética se utilizó una mezcla producida según muchas recetas, formada por: cal (50-75%), fluorina (0-17%), bauxita (0-32%) y escoria aluminosa (8-22%). Los datos han sido procesados en los programas de cálculo EXCEL y MATLAB, resultando una serie de correlaciones entre el grado de desulfuración y la composición química de la escoria, la cantidad de escoria respectivamente, tanto para las cargas burbujeadas con argón como no burbujeadas.
Comparative analysis of two processes for desulphurization of battery paste  [PDF]
D. Malak,A. Rodak,A. Studnicka,W. Soszyński
Journal of Achievements in Materials and Manufacturing Engineering , 2012,
Abstract: Purpose: The paper touches the problem of recycling battery scrap and desulphurization methods. The aim of this paper is to compare sodium method and new amine method for desulphurization of battery paste. Also the comparison of this methods refers to environmental and technological aspects of lead smelting.Design/methodology/approach: Base of the comparison of two different methods were tests of melting of desulphurized battery paste in a rotary-tilting furnace by BJ Industries Company.Findings: Both methods of desulphurization allow to reduce amount of sulphur to less than 1%. The economic considerations determine the degree of desulphurization of battery paste. Amine method allows to reduce sulphur to a degree of about 0,5% maintaining favorable technical and economical parameters.Research limitations/implications: Effectiveness of amine method was confirmed in the pilot-scale tests, but it’s difficult to say what will be the results of desulphurization by this method in industrial scale.Originality/value: The value of this paper lies in demonstrating the possibilities of application of the new amine method of battery paste desulphurization, compared to for commonly used methods.
SiO2骨架支撑MoOx催化剂用于正庚烷异构化反应  [PDF]
柴松海,王新平,汪颖军,蔡天锡
催化学报 , 2003,
Abstract: ?采用SEM,XRD,EDS及N2吸附-脱附方法研究了骨架型MoOx-SiO2催化剂和负载型MoOx/SiO2催化剂的物理化学结构,并在常压固定床流动反应器上考察了两种催化剂对正庚烷异构化反应的催化性能.结果表明,在MoOx-SiO2催化剂中,44.6%的SiO2即可起到很好的骨架支撑作用;MoOx晶相以足够大的空间区域聚集包裹在SiO2骨架中,形成类似MoOx催化剂的独特的中孔结构.与MoOx催化剂相比,MoOx-SiO2催化剂显著提高了机械强度,并维持了MoOx催化剂较高的活性和选择性.由于钼物种和载体之间的相互作用,负载型MoOx/SiO2催化剂表现出较低的比活性.脉冲注入H2S实验结果表明,MoOx-SiO2催化剂具有较好的抗硫性能.
Desulphurization and denitrification processes in the energy industry
Virèíková Edita
Acta Montanistica Slovaca , 1998,
Abstract: The world′s problem of environmental pollution is also an important problem in the Slovak Republic. One of the biggest sources of air pollution is the combustion of low quality fossil fuels. During the burning of coal, combustible types of sulfur, like organic and pyritic, are oxidized and form sulfur dioxide or trioxide. Nitrogen oxides in chimney gases are generally found in three forms: NO, NO2 and N2O. It is more difficult to remove NOX than SO2 because of the structure of NOx. For this reason it is necesary to keep lower NOx emissions in the system by various methods. This paper surveys the current status of the desulphurization and denitrification processes in the energy industry.
MoOx促进的Pt基催化剂用于低温水汽变换反应  [PDF]
催化学报 , 2015, DOI: 10.1016/S1872-2067(14)60294-1
Abstract: ?通过浸渍还原法制备了不同比例的Pt-Mo/SiO2催化剂,采用X射线衍射、透射电镜、X射线近边吸收谱和X射线光电子能谱表征了Pt-Mo/SiO2催化剂的组成、结构及价态.研究结果表明,少量MoOx修饰Pt-Mo/SiO2催化剂在低温水汽变换反应中表现出比Pt/SiO2催化剂更高的催化活性,过量MoOx包覆的Pt-Mo/SiO2催化剂活性较低.低温水汽变换反应活性来自于Pt与表面MoOx的界面协同作用,限域在Pt纳米颗粒表面的MoOx表现出较低价态,高分散MoOx纳米岛修饰的Pt纳米颗粒是低温水汽变换反应的活性结构.
Oxidation of thiophene with hydrogen peroxide catalyzed by activated carbon and formic acid
活性炭及甲酸催化过氧化氢氧化噻吩脱硫研究

YU Guo-xian,LU Shan-xiang,CHEN Hui,ZHU Zhong-nan,
余国贤
,陆善祥,陈 辉,朱中南

燃料化学学报 , 2005,
Abstract: Reaction feed was prepared as follows: thiophene selected as model organosulfur compound in gasoline was dissolved in n-octane. The adsorption of thiophene in n-octane by activated carbon was investigated. The oxidant was 30% aqueous solution of hydrogen peroxide. Oxidative desulfurization with 30 % H_2O_2 in the presence of the activated carbon and formic acid was studied. Catalytic performance of the activated carbon and the effect of reaction conditions on oxidative removal of thiophene were investigated. Experimental results indicated that performic acid and hydroxyl radical produced in situ are coupled to oxidize model organosulfur compound with desulfurization ratio of over 85%. Catalytic performance of the combination of activated carbon and formic acid is higher than that of only formic acid. Formic acid concentration, activated carbon dosage and initial hydrogen peroxide concentration, reaction temperature affect the oxidative removal of thiophene.
On the kinetics of the hydrogen evolution reaction on Ni-MoOx composite catalysts in alkaline solutions  [PDF]
Jovi? Borka M.,La?njevac Uro? ?.,Jovi? Vladimir D.,Gaji?-Krstaji? Ljiljana M.
Journal of the Serbian Chemical Society , 2012, DOI: 10.2298/jsc110621185j
Abstract: MoO3 particles were co-deposited with Ni onto smooth or rough Ni supports from modified Watt’s baths of different compositions. Morphology and composition of the electrodeposits were characterized by means of cyclic voltammetry, X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. The electrocatalytic activity of the composite catalysts for H2 evolution in alkaline solutions was determined by quasi-stationary polarization curves. Activity increases with MoOx content in the Ni deposit up to a limiting value. Composite Ni-MoOx catalyst performed high catalytic activity, similar to that of commercial Ni-RuO2 catalyst. Stability tests showed that Ni-MoOx codeposits are stable under condition of constant current and exhibit excellent tolerance to repeated short-circuiting.
EXTRACTION APPROACH FOR DESULPHURIZATION AND DEAROMATIZATION OF MIDDLE DISTILLATES  [PDF]
P. Petkov,J. Tasheva,D. Stratiev
Petroleum and Coal , 2004,
Abstract: Reduction of sulphur content in diesel to near zero levels plays a significant role for improving air quality. Hydrodesulphurization is the most developed desulphurization technology today. However meeting the 10 ppm sulphur limit in the diesel fuel requires expensive revamps of the existing hydrotreating units or building of new grass root units. This specification also necessitates running the units at higher severity which is related to higher energy consumption and higher amount of emissions of CO2 release in the atmosphere. Extraction of sulphur and aromatic compounds from the middle distillates offers another opportunity for desulphurization and dearomatization of diesel fractions at low temperatures without participation of hydrogen. This process allows a substantial reduction in the energy consumption. It was found in this study that by extraction of heating gas oil and hydrotreated diesel with the selective solvents, methanol, furfural, and ethylene glycol the sulphur content could be reduced sevenfold and the aromatics content threefold respectively. The extraction of the sulphur compounds from the hydrotreated diesel was about 40% more efficient than that of the heating gas oil, while the extraction of the aromatics from the hydrotreated diesel was twice as high as that from the heating gas oil. This indicates that the chemical nature of the middle distillate fractions plays a significant role on the efficiency of the extraction process.
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