کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
169621 458023 2007 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Chemical kinetic considerations for postflame synthesis of carbon nanotubes in premixed flames using a support catalyst
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Chemical kinetic considerations for postflame synthesis of carbon nanotubes in premixed flames using a support catalyst
چکیده انگلیسی

Multiwalled carbon nanotubes (MWCNTs) on a grid supported cobalt nanocatalyst were grown, by exposing it to combustion gases from ethylene/air rich premixed flames. Ten equivalence ratios (ϕ)(ϕ) were investigated, as follows: 1.37, 1.44, 1.47, 1.50, 1.55, 1.57, 1.62, 1.75, 1.82, and 1.91. MWCNT growth could be observed for the range of equivalence ratios between 1.45 and 1.75, with the best yield restricted to the range 1.5–1.6. A one-dimensional premixed flame code with a postflame heat loss model, including detailed chemistry, was used to estimate the gas phase chemical composition that favors MWCNT growth. The results of the calculations show that the mixture, including the water gas shift reaction, is not even in partial chemical equilibrium. Therefore, past discussions of compositional parameters that relate to optimum carbon nanotube (CNT) growth are revised to include chemical kinetic effects. Specifically, rapid departures of the water gas shift reaction from partial equilibrium and changes in mole fraction ratios of unburned C2 hydrocarbons to hydrogen correlate well with experimentally observed CNT yields.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Combustion and Flame - Volume 151, Issue 3, November 2007, Pages 542–550
نویسندگان
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