Boreskov Institute of Catalysis of the Siberian Branch of Russian ...

OP-III-7with the conventional reactor is due to both the increase in CO conversion and the diminutionof the molar flowrate of the process gas [5]. The reduction of the catalyst volume (reactorlength) to reach a required X CO level was also analyzed for increasing operating pressures(results not shown). Medium pressures of around 5 atm appear favorable to achieve anoticeable diminution of the reactor length with moderate increase on compression andmanufacture costs.The performance of the non-isothermal WGS-MR for operation without sweep-gas hasbeen also studied. This alternative arises as highly attractive since no separation / purificationsteps are required for the pure H 2 permeated gas. Figure 2 presents a comparison of H 2 -partialpressure (P H2 ) axial profiles for operation with and without sweep gas, for both process gasand permeate sides (P H2,R and P H2,P , respectively). The increase in operating pressure resultsalso beneficial for the operation without sweep gas but in a lower extent when compared withthe operation with sweep gas. This behavior obeys to the elimination of the dilution effectprovided by the sweep gas. The operation without sweep gas leads to lightly lower COconversions but a pure H 2 stream is attained in the reactor shell. Besides, an improvedutilization of the catalyst in the reactor length is achieved.X CO100806040200CRMR-P=1 atm320 340 360 380 400 420 440 460T(°C)1020 40MR-P=100 atmFigure 1: influence of the operating pressure on the MRperformance (for CR the performance is unaltered byincreasing pressures). Process gas inlet flowrate: 9.58 10 –3mol/s. Inlet dry basis concentrations: H 2 : 43.5%, CO: 8%.Sweep gas flowrate at inlet conditions (F SG,i ): 50 l/min.References:p H2(atm)4.54.03.53.02.52.01.51.00.5p H2,Rp H2,RF SG,i ~ 0F SG,i = 50 l/minp H2,Pp H2,P0.00.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14z(m)Figure 2: H 2 partial pressures in the process gas side (dottedlines) and permeate side (solid lines), for operation of MR withand without sweep gas (F SG,i = 50 l/min and F SG,i = 0,respectively). Operating conditions as in Figure 1.1. J.S. Oklany, K. Hou, R. Hughes; App. Catal. A, 170 (1998) 13.2. S. Tosti, L. Bettinali, V. Violante; Int. J. Hyd. Energy, 25 (2000) 319.3. A. Criscuoli, A. Basile, E. Drioli; Catal. Today. 56 (2000) 53.4. M.E. Adrover, E. López, D. Borio, M. Pedernera; Studies on Surface Science and Catalysis, Elsevier,Amsterdam, Vol. 167, 2007, 183-188.5. M.E. Adrover, E. López, D. Borio, M. Pedernera; «Análisis de un reactor de membrana no isotérmico parala reacción de water-gas shift», XV Argentinian Congress of Catalysis, La Plata, Argentina, 12-16/11/2007.Acknowledgments: Support of this work through Universidad Nacional del Sur (UNS), Consejo Nacionalde Investigaciones Científicas y Tecnológicas (CONICET) and Agencia Nacional de Promoción de Ciencia yTecnología (ANPCyT) is gratefully acknowledged.104