Addition/Correction pubs.acs.org/EF
Cite This: Energy Fuels 2018, 32, 961−961
Correction to Coupling Red-Mud Ketonization of a Model Bio-Oil Mixture with Aqueous Phase Hydrogenation Using Activated Carbon Monoliths Justin Weber, Aaron Thompson, Jared Wilmoth, Robert J. Gulotty, Jr., and James R. Kastner* Energy Fuels 2017, 31 (9), 9529−9541. DOI: 10.1021/acs.energyfuels.7b01500 S Supporting Information *
the absence of diffusional control.38 The larger Mears criterion for Pd/C granules suggests that the lower ketone conversion and product STY compared to Pd/ACM were, in part, due to greater external mass transfer resistances in the Pd/C particle (or superior mass transfer rates for Pd/ACM). Similar results for Pd on carbon nanofibers grown on ceramic monoliths (Pd/ CNFM) have been reported.16 In comparison to Pd/carbon pellets, Pd/CNFM generated higher conversions and product selectivity in the hydrogenation of 4-carboxybenzaldehyde as a result of significantly lower internal mass transfer resistance for the monolith. 4. Conclusions. Page 9549, Last Paragraph: The significantly higher STYs and selectivity toward products and higher conversions were in part due to the higher Pd dispersion and larger external H2 mass transfer rates in Pd/ACM.
During further analyses, we discovered an error in our spreadsheet calculations to determine the external and internal mass transfer effects on reaction kinetics. We incorrectly calculated the Schmidt number (Sc = ν/DAB), which subsequently affected the Mears (external mass transfer effect) and Wiesz−Prater (internal mass transfer effect) criterions for the granules. We also incorrectly used the viscosity of water at room temperature (1 cP) instead of at 180 °C (0.15 cP). Correcting these errors changes the values in Table 2 and Table S3 of the Supporting Information and indicates that external mass transfer was ratelimiting for reactions with the granules but not the carbon monolith. However, the overall conclusions of the results do not change as a result of these corrections. 3.4. Comparison of Pd/C Monoliths and Granules and Two-Stage Analysis. Page 9538, First Paragraph: The Mears criteria for the Pd/C granules and cyclopentanone (selected because it had the lowest diffusivity) and H2 reaction rates were not significantly smaller than 1, indicating that external mass transfer was potentially rate-limiting, especially for H2 (see the Supporting Information and Table S1 of the Supporting Information). Mears criterion calculations for Pd/ACM suggest that H2 external mass transfer was not rate limiting (Table S1 of the Supporting Information). For example, the H2 Mears criterion ranged from 3 × 10−6 to 14 × 10−6 (assuming a first-order reaction) as the LHSV increased from 1.2 to 6.2 h−1 for Pd/ACM, where a value less than 0.15 indicates that external mass transfer is not rate limiting.37 The Wiesz−Prater criteria for CPON and H2 were not significantly different for Pd/C granules compared to Pd/ACM and approached the CWP criterion of 0.11 at a LHSV of 6.2 h−1 (Table 2). CWP of 6 indicates definitive intraparticle diffusional resistance, and a value less than 0.3 suggests
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ASSOCIATED CONTENT
S Supporting Information *
The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.energyfuels.7b03924. Corrections to the Supporting Information (PDF)
Table 2. Estimated Intraparticle Mass Transfer Limitations for Pd/Carbon Catalysts (300 psig, 180 °C)a Pd/C granules Qg/Ql 200 100 66.7 50 25 12.5
Pd/ACM
LHSV (h−1)
CPON r (mmol g−1 h−1)
CWP,CPON
H2 −r (mmol g−1 h−1)
CWP,H2
0.77 1.54
0.189 0.34
0.010 0.014
0.036 0.229
0.003 0.019
3.1 6.2
0.73 1.37
0.030 0.057
0.409 1.253
0.035 0.107
LHSV (h−1)
CPON r (mmol g−1 h−1)
CWP,CPON
H2 −r (mmol g−1 h−1)
CWP,H2
0.39 0.78 1.2
0.22 0.44 0.67
0.001 0.002 0.004
0.347 0.65 0.91
0.008 0.016 0.022
3.1 6.2
1.49 3.17
0.006 0.015
2.83 4.59
0.068 0.111
a Qg is the gas flow rate. Ql is the liquid flow rate. CPON is cyclopentanone. LHSV = (QlρB)/Wcat. CWP is the Wiesz−Prater criterion. Wcat is the catalyst amount.
© 2017 American Chemical Society
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DOI: 10.1021/acs.energyfuels.7b03924 Energy Fuels 2018, 32, 961−961
