ساخت نانو كاتالبيست IF-WS2 بر پايه MCM-41 به روش تلقيح مرطوب و ارزيابي آن در واكنش هيدروژناسيون

چكيده انگليسي :

Synthesis of Nanocatalyst of IF WS2 on Support of MCM 41 via Impregnation Method and its Activity Evaluation in Hydrogenation Reaction Mohammad Vatani m vatani@ce iut ac ir June 22 2011 Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Seyyed Mohammad Ghoreishi ghoreshi@cc iut ac ir Mehran Ghiaci mghiaci@cc iut ac irAbstract In recent years nanotechnology as a multidisciplinary science has led to immense evolution in many fields ofscience and industries Production of new material with novel specification and structure is the most importantoutcome of nanotechnology These materials will increase efficiency of industrial processes Nanoparticles arecharacterized by a high surface volume ratio and this has opened the field to the applications where the surfaceproperties result important The chemical and physical properties of nanoparticles sensibly differ from those ofbulk material and of isolated atoms and molecules In so far the interest in their respects derives from the drasticchange that electric magnetic catalytic and optical properties undergo when the size of a material is reducedfrom infinite to nanometric dimensions Catalysis science and technology is a major field in applied science thattakes advantage of nanotechnology very well With new policy in reducing environmental pollution there aremany ongoing researches in producing new catalyst to diminish contamination of fuel to environmentalstandards The objective of this thesis was to reach to an optimum method to produce a catalyst with novelspecification and high activity Common methods in producing desulfurization catalyst are deposition of activephase on a support such as alumina or mesoporous materials by impregnation method Agglomeration ofnanoparticles crystal inside pores and blocking of pores of MCM 41 are damages of impregnation method In thisresearch two new methods was used to produce WS2 supported MCM 41 catalyst In the first method synthesisof nanoparticles by reverse micelle method was followed by uv vis spectroscopy MCM 41 was synthesized withhydrothermal method Incorporation of active phase into MCM 41was performed with proposed method Effectof ultrasonic waves on reverse micelle and impregnation of nanoparticle into MCM 41 pores was studied Elemental analysis of prepared catalyst showed presence of tungsten and sulfur in solid It maybe said reversemicelle is broken by ultrasonic waves and incorporation of nanoparticle into mesoporous pores was done Synthesis of nanaparticles inside microemulsion with other concentration of precursor showed size selectivity ofincorporation of WS2 nanoparticles In the other method precursor of active phase was added to the gel ofprecursor of MCM 41 This leads to incorporation of metals into mesoporous framework In order to compare theoutcome of two methods XRD ASAP BET BJH XRF and EDAX analysis were carried out Although in thefirst method dispersion of active phase on the support was uniform loading of active phase could not satisfy thedesulfurization reaction Hence in order to survey the catalyst activity in the reaction conditions a catalyst with15 percent Ni W supported on MCM 41 was prepared by second proposed method and was evaluated inhydrodesulphurization of Tehran oil refinery naphtha Hydrodesulfurization of naphtha was carried out in a fixedbed reactor at 15bar 310 C LHSV 4hr 1 The results showed that nickel tungsten supported on MCM 41synthesized by direct hydrothermal method led to removal of 98 percent of sulfur from naphtha Keywords nanoparticle tungsten disulfide microemulsion MCM 41 hydrodesulfurization

وطني، محمد

ساخت نانو كاتالبيست IF-WS2 بر پايه MCM-41 به روش تلقيح مرطوب و ارزيابي آن در واكنش هيدروژناسيون

نانو ذرات , دي سولفيد تنگستن , ميكروامولسيون , گوگرد زدايي