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V adsorbed = ΔArea n ×F c SW
Includes the volume adsorbed per pulse and the cumulative volume adsorbed.
Pulse n area n Δarea n V adsorbed (cm 3 /g STP) Cumulative quantity (cm 3 /g STP)
1 0 0.0105809790 0.2800256 0.2800256
2 0.000471772 0.0105338018 0.2787771 0.5588027
3 0.00247767 0.0081033090 0.2144541 0.7732567
4 0.009846683 0.0007342960 0.0194331 0.7926899
5 0.010348201 0.0002327780 0.0061605 0.7988504
6 0.010030243 0.0005507360 0.0145752 0.8134256
7 0.009967717 0.0006132620 0.0162300 0.8296556
8 0.010580979 0 0.0000000 0.8296556

Gram molecular weight

Gram molecular weight is the weighted average of the number of moles of each active metal in the catalyst. Since this is a monometallic catalyst, the gram molecular weight is equal to the molecular weight of palladium (106.42 [g/mol]). The GMC Calc is calculated using [link] , where F is the fraction of sample weight for metal N and W atomicN is the gram molecular weight of metal N (g/g-mole). [link] shows the calculation for this experiment.

GMW Calc = 1 ( F 1 W atomic1 ) + ( F 2 W atomic2 ) + ... + ( F N W atomicN ) MathType@MTEF@5@5@+=faaagCart1ev2aaaKnaaaaWenf2ys9wBH5garuavP1wzZbqedmvETj2BSbqefm0B1jxALjharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8FesqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=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@5ADE@
GMW Calc = 1 ( F 1 W atomicPd ) = W atomicPd F 1 = 106 .42 g g-mole 1 =106 .42 g g-mole

Metal dispersion

The metal dispersion is calculated using [link] , where PD is the percent metal dispersion, V s is the volume adsorbed (cm 3 at STP), SF Calc is the calculated stoichiometry factor (equal to 2 for a palladium-hydrogen system), SW is the sample weight and GMW Calc is the calculated gram molecular weight of the sample [g/g-mole]. Therefore, in [link] we obtain a metal dispersion of 6.03%.

PD = 100 × ( V s × SF Calc SW × 22414 ) × GMW Calc MathType@MTEF@5@5@+=faaagCart1ev2aaaKnaaaaWenf2ys9wBH5garuavP1wzZbqedmvETj2BSbqefm0B1jxALjharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8FesqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9Gqpi0dc9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeiuaiaabseadaWfqaqaaaWcbaaabeaakiabg2da9iaabgdacaqGWaGaaeimaiabgEna0oaabmaabaWaaSaaaeaacaqGwbWaaSbaaSqaaiaabohaaeqaaOGaey41aqRaae4uaiaabAeadaWgaaWcbaGaae4qaiaabggacaqGSbGaae4yaaqabaaakeaacaqGtbGaae4vaiabgEna0kaabkdacaqGYaGaaeinaiaabgdacaqG0aaaaaGaayjkaiaawMcaaiabgEna0kaabEeacaqGnbGaae4vamaaBaaaleaacaqGdbGaaeyyaiaabYgacaqGJbaabeaaaaa@4FBF@
PD=100× ( 0 .8296556 [ cm 3 ] ×2 0 .1289 [ g ] ×22414 [ cm 3 mol ] ) ×106 .42 [ g g-mol ] = 6.03 %

Metallic surface area per gram of metal

The metallic surface area per gram of metal is calculated using [link] , where SA Metallic is the metallic surface area (m 2 /g of metal), SW Metal is the active metal weight, SF Calc is the calculated stoichiometric factor and SA Pd is the cross sectional area of one palladium atom (nm 2 ). Thus, in [link] we obtain a metallic surface area of 2420.99 m 2 /g-metal.

SA Metallic = ( V S SW Metal ×22414 ) × ( SF Calc ) × ( 6 .022×10 23 ) ×SA Pd
SA Metallic = ( 0 .8296556 [ cm 3 ] 0 .001289 [ g metal ] ×22414 [ cm 3 mol ] ) × ( 2 ) × ( 6 .022×10 23 [ atoms mol ] ) ×0 .07 [ nm 2 atom ] =2420 .99 [ m 2 g-metal ]

Active particle size

The active particle size is estimated using [link] , where D Calc is palladium metal density (g/cm 3 ), SW Metal is the active metal weight, GMW Calc is the calculated gram molecular weight (g/g-mole), and SA Pd is the cross sectional area of one palladium atom (nm 2 ). As seen in [link] we obtain an optical particle size of 2.88 nm.

APS= 6 D Calc × ( W s GMW Calc ) × ( 6 .022×10 23 ) ×SA Metallic
APS= 600 ( 1 .202×10 -20 [ g Pd nm 3 ] ) × ( 0 .001289 [ g ] 106 .42 [ g Pd mol ] ) × ( 6 .022×10 23 [ atoms mol ] ) × ( 2420 .99 [ m 2 g Pd ] ) =2 .88nm

In a commercial instrument, a summary report will be provided which summarizes the properties of our catalytic material. All the equations used during this example were extracted from the AutoChem 2920-User's Manual.

Summary report provided by Micromeritics AuthoChem 2920.
Properties Value
Palladium atomic weight 106.4 g/mol
Atomic cross-sectional area 0.0787 nm²
Metal density 12.02 g/cm³
Palladium loading 1 wt%
Metal dispersion 6.03%
Metallic surface area 2420.99 m²/g-metal
Active particle diameter (hemisphere) 2.88 nm

References

  • A. J. Canty, Accounts Chem. Res. , 1992, 25 , 83.
  • H. S. Fogler, Elements of Chemical Reaction Engineering , Prentice-Hall, New York (1992).
  • Micromeritics Instrument Corporation, AutoChem 2920 – Automated catalyst characterization system – Operators Manual , V4.01 (2009).
  • M. O. Nutt, K. N. Heck, P. Alvarez, and M. S. Wong, Appl. Catal. B-Environ. , 2006, 69 , 115.
  • M. O. Nutt, J. B. Hughes, and M. S. Wong, Environ. Sci. Technol. , 2005, 39 , 1346.
  • P. A. Webb and C. Orr, Analytical Methods in Fine Particle Technology , Micromeritics Instrument Corp, 1997.
  • R. Zhang, J. A. Schwarz, A. Datye, and J. P. Baltrus, J. Catal. , 1992, 138 , 55.

Questions & Answers

how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
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I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
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Porter
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Yasmin
what is the function of carbon nanotubes?
Cesar
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
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name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
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Source:  OpenStax, Physical methods in chemistry and nano science. OpenStax CNX. May 05, 2015 Download for free at http://legacy.cnx.org/content/col10699/1.21
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