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Novel approaches to the production of higher alcohols from synthesis gas. Quarterly technical progress report No. 16, July 1, 1994-- September 30, 1994

Description: Accomplishments for Task 2, liquid-phase, higher alcohol process with recycle of lower alcohols, are as follows: (1) a new reactor overhead system design has significantly improved retention of slurry oil during reactor operation at high temperature, ca. 375{degrees}C; (2) a series of ``blank`` (without catalyst) runs were made at 375{degrees}C to evaluate thermal stability of three potential slurry liquids, Drakeol{reg_sign}, Ethylflo{reg_sign} 180 and perhydrofluorene; and (3) the rate of methanol formation with the Cu/ZnO BASF S3-86 ``low temperature`` methanol synthesis catalyst was a strong function of stirrer speed at a ``standard`` set of operating conditions. This result suggest that the reaction rate is influenced or controlled by gas/liquid mass transfer, and may explain the previously-observed discrepancy between results from this laboratory and those from Air Products.
Date: March 1, 1996
Creator: Roberts, G.W.
Partner: UNT Libraries Government Documents Department

Novel approaches to the production of higher alcohols from synthesis gas. Quarterly progress report, April 1, 1994--June 30, 1994

Description: Under Task 2, four sets of methanol synthesis run were conducted with BASF S3-86 ``low pressure``, Cu/ZnO methanol synthesis catalyst. The objectives were: (1) to reproduce the data obtained with this catalyst by researchers at Air Products and Chemicals, Inc., and: (2) to determine whether the previously-observed problem of catalyst poisoning by metal carbonyls had been eliminated. The catalyst poisoning problem appears to be resolved, although there is a need for additional data on the capacity of activated carbon for iron and nickel carbonyl absorption. However, under apparently comparable conditions, the activity of the BASF S3-86 catalyst in the present experiments was lower than the activity measured at Air Products. The difference tentatively has been attributed to differences in the catalyst activation procedure. Problems with reliability of the experimental equipment were experienced: these problems limited the quality and quantity of the experimental data.
Date: May 1, 1996
Creator: Roberts, G.W.
Partner: UNT Libraries Government Documents Department

Novel approaches to the production of higher alcohols from synthesis gas. Quarterly technical progress report No. 19, April 1, 1995--June 30, 1995

Description: Three runs were carried out in the continuous stirred autoclave reactor with Englehard Zn-0312 T 1/8 {open_quotes}zinc chromite{close_quotes} catalyst and with decahydronaphthalene (Decalin{reg_sign}) as the slurry liquid. One short run, which was prematurely terminated by operational problems, was designed to define the effect of stirrer speed on catalyst performance. Two longer runs completed the data base required for kinetic characterization of the unpromoted {open_quotes}zinc chromite{close_quotes} catalyst. Although analysis of the data is not complete, it is evident that: (1) stirrer speed has no significant effect on the measured reaction rate, and; (2) carbon dioxide appears to inhibit catalyst activity.
Date: October 10, 1996
Creator: Roberts, G.W.
Partner: UNT Libraries Government Documents Department

Novel approaches to the production of higher alcohols from synthesis gas. Quarterly technical progress report No. 20, July 1, 1995--September 30, 1995

Description: Standard thermal stability tests were carried out on four liquids: decahydroquinoline (DHQ); 1, 3-Di-4 piperidylpropane (134PPDP), Naphthenic Base 37 and tetrahydronaphthalene (tetralin). Tetralin was more stable than decahydronaphthalene (Decalin{reg_sign}), and THQ was slightly less stable. Both tetralin and THQ should be evaluated further as slurry liquids in the presence of catalyst and syngas. Naphthenic Base 37 and 134PPDP do not have satisfactory thermal stability. Vapor pressure osmometry (VPO) was shown to be an unreliable technique for measuring the average molecular weight of slurry liquids. Gas chromatography/mass spectroscopy (GUMS) is a more accurate technique for pure compounds.
Date: September 5, 1996
Creator: Roberts, G.W.
Partner: UNT Libraries Government Documents Department

ENGINEERING EVALUATION OF HOT-GAS DESULFURIZATION WITH SULFUR RECOVERY

Description: Engineering evaluations and economic comparisons of two hot-gas desulfurization (HGD) processes with elemental sulfur recovery, being developed by Research Triangle Institute, are presented. In the first process, known as the Direct Sulfur Recovery Process (DSRP), the SO{sub 2} tail gas from air regeneration of zinc-based HGD sorbent is catalytically reduced to elemental sulfur with high selectivity using a small slipstream of coal gas. DSRP is a highly efficient first-generation process, promising sulfur recoveries as high as 99% in a single reaction stage. In the second process, known as the Advanced Hot Gas Process (AHGP), the zinc-based HGD sorbent is modified with iron so that the iron portion of the sorbent can be regenerated using SO{sub 2} . This is followed by air regeneration to fully regenerate the sorbent and provide the required SO{sub 2} for iron regeneration. This second-generation process uses less coal gas than DSRP. Commercial embodiments of both processes were developed. Process simulations with mass and energy balances were conducted using ASPEN Plus. Results show that AHGP is a more complex process to operate and may require more labor cost than the DSRP. Also capital costs for the AHGP are higher than those for the DSRP. However, annual operating costs for the AHGP appear to be considerably less than those for the DSRP with a potential break-even point between the two processes after just 2 years of operation for an integrated gasification combined cycle (IGCC) power plant using 3 to 5 wt% sulfur coal. Thus, despite its complexity, the potential savings with the AHGP encourage further development and scaleup of this advanced process.
Date: May 31, 1998
Creator: ROBERTS, G.W.; PORTZER, J.W.; KOZUP, S.C. & GANGWAL, S.K.
Partner: UNT Libraries Government Documents Department