نتایج جستجو برای: natta catalysts

تعداد نتایج: 33137  

Journal: :journal of physical & theoretical chemistry 2008
omid moradi mohammad yari s. sedaghat

in this research we used heavy propylene tetramer (hpt) and a1c13 —bf3 (lewis acids) ascatalyst and ethanol, n-propanol and n-butanol as co-catalyst. using lewis acids as catalyst, thehpts form molecules with higher molecular weight. since the raw materials of the reaction are byproducts of other reactions, are not pure and contain various compounds with different m.w andalso different chemical...

Journal: :علوم و تکنولوژی پلیمر 0
علی فرهنگیان کاشانی حسین عابدینی محمدرضا کلایی

a linear low density polyethylene (lldpe) production process, including two- fuidized bed reactors in series (fbrs) and other process equipment, was completely simulated by aspen polymer plus software. fluidized bed reactors were considered as continuous stirred tank reactors (cstr consisted of polymer and gas phases). poly-srk and nrtl-rk equations of state were used to describe polymer and no...

Journal: :علوم و تکنولوژی پلیمر 0
محمد سلطانیه احمد رمضانی سعادت آبادی علی دشتی جعفر مختاری

in this article, a complete model for the mixed flow slurry reactor for polymerization of ethylene to high density polyethylene in the presence of ziegler-natta catalyst is presented. in addition to the effects of the multiple active sites, the effect of other important parameters such as the catalyst concentration, co-catalyst, hydrogen, monomer, impurities and pressure on the mass-average and...

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 2009
ahmad tavasoli mohammad irani ali nakhaeipour yadollah mortazavi abas ali khodadadi

the potential of carbon nanotubes (cnt) supported cobalt catalysts for fischer-tropsch (ft) reaction is shown. using the wet impregnation method cobalt on carbon nanotubes catalysts were prepared with cobalt loading varying from 15 to 45 wt. %. the catalysts are characterized by different methods including: bet physisorption, x-ray diffraction, hydrogen chemisorption, and temperature-programmed...

Journal: :iranian journal of catalysis 2016
rajesh k. singh shikha sharma akshdeep sandhar manpreet saini sahil kumar

1,5-benzodiazepines are regarded as one of the most important classes of heterocyclic compounds as privileged structures and have vast range of applications in the field of medicine and chemistry. they are therefore attractive synthetic targets for organic and medicinal chemist. the current review article mainly covers the multicomponent green chemistry approaches for the synthesis of 1,5-benzo...

2010
Shuli Yan Craig DiMaggio Siddharth Mohan Manhoe Kim Steven O. Salley K. Y. Simon Ng

Heterogeneous catalysts are promising for the transesterification reaction of vegetable oils to produce biodiesel and have been studied intensively over the last decade. Unlike the homogeneous catalysts, heterogeneous catalysts can be easily separated from reaction mixture and reused for many times. They are environmentally benign and could be easily operated in continuous processes. This revie...

2005
John E. Bercaw

Highly electron deficient scandocene derivatives of the types (q5-CsMe&ScR, {(q5-CsMe4)2SiMe2}ScR and {(q5-C5H3CMe3)2SiMe2}ScR catalyze the polymerization of ethylene, the head-to-tail dimerization of a olefins, the cyclization of a,w dienes to meth lene cycloalkanes, and the branching of 1,4 pentadienes to isoprenes. The mechanisms oythe individual steps have been studied. Key steps involve se...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید