Is it with respect to the catalyst or the weight of the catalyst divided by its molecular weight.
Actually we are synthesizing Tetrazoles from Benzonitriles.
100 mg of benzonitrile was reacted with 20.75 mg of silver nanoparticles (The nanoparticles contain pure Ag of 40-42 nm size in zero oxidation state as confirmed by HRTEM, EDX and other experiments).
M. Wt of benzonitrile is 103.04 g/mol i.e., the reactant is 0.97 mmol. Now if 20.75 mg of silver particles are taken as catalysts which has the atomic weight 107.86 amu. How much catalyst is used? What should I report in the paper?
Is it 19.58 mol% or 19.58 mmol%??
In this catalyst weight percent, what would you need to calculate, is that you need to calculate any of these 1) atom economy, 2) Conversion in WHSV/LHSV, and 3) catalyst efficiency. Nevertheless, I considered the correlation of amu and mass of the catalyst (except atom economy case) is insignificance. If you need to calculate conversion in terms of WHSV/LHSV, just do calculate through over all weight of reactant divide by weight of the catalyst per hour (unit less). Other cases are product dependence; it is expressed by product ratios as desired product/ total products. If your catalyst may be supported one, then you can considered that silver particles are active sites, which you known weight percent of catalyst has taken. Note, Mg of weight is always expressed as mmol.
Thank You for your kind replies.
The catalyst is added as solid material which can be recovered simply by centrifugation. So is it correct to report as w/v?
The reaction condition was optimized using 20.75 mg of pure Ag for 100 mg of benzonitrile. Considering the atomic weight of Ag to be 107.86 atomic mass unit if we calculate the amount of silver used it comes out to be 0.00019238 mol which I believe can be written as 19.23 mmol%. However, if we calculate the amount of benzonitrile reactant . It comes out to be 0.97 mmol i.e., 0.97 x 10-3 mol and taking 20% of it and calculating the amount of silver used also gives 20.75 mg.
So my confusion still persists. While reporting the reaction should we write the amount of catalyst used as 19.23 mol% (approx 20 mol%) or 20 mmol%.
Centrifugation is doesn’t matter for w/v expression, it is agglomeration of solid particles from free dispersion of impurities. Moreover, it is not important that we have to mention as mol % of catalyst (on unsupported catalyst), in the description of optimization part we can just mentioned it as 20 mg of catalyst has been used. If you represent in percent, then it is no need to represent as % mol, because the unit of g is cancelled out (see this (20.75 X 103 g)/ (107.86 g). Therefore wt % of catalyst (not mol %) representation is to better for report.
Reporting catalyst in Wt % is better way of expressing catalyst amount in a reaction.
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