55 1 Vol 55 1 2004 1 Journal of Chemical Industry and Engineering (China) January 2004 (, 116023) /,,, H 2 3 % (mol) 15 %(mol), H 2 8 %(mol) 150 110 10 6 h - 1, 90 % TQ 032141 A 0438-1157 (2004) 01-0042 - 06 CATALYTIC COMBUSTIO OF HYD RO GE/ AIR I MICROCHAEL REACTOR CAO Bin, CHE Guangwen and YUA Quan ( Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China) Abstract The catalytic combustion reaction of hydrogen/ air mixture was studied in a microchannel reactor The effects of operation conditions on reactor behavior were investigated in detail by using both mathematic modeling and experiment work Explosive mixtures of hydrogen/ air [ 3 % (mol) 15 % (mol) ] were safely handled in this reactor The results showed that catalytic combustion reaction can be operated at high space velocity, isothermal and kinetic controlled regimes Under the conditions of inlet hydrogen concentration of 8 % (mol), reaction temperature of 150, space velocity of 10 6 h - 1, hydrogen conversion was still higher than 90 % Keywords microchannel reactor, hydrogen, catalytic combustion 20 80,,,,, [1 ] [3, ],,,, [2 ] 2002-09 - 20, 2003-01 - 20 : :,, 27, Received date : 2002-09 - 20 Corresponding author : Prof YUA Quan E - mail : qyuan @ : ( o1 20176057, o120122201, dicp1ac1cn o 20396009), (o12001cb711203) Foundation item : supported by the ational atural Science (o G2000026401) Foundation of China ( o120176057, o120122201, o 20396009), the Key Program for International Cooperation of Science and Technology (o12001cb711203) and the State Key Development Program for Basic Research of China (o G20000206401) 1994-2006 China Academic Journal Electronic Publishing House All rights reserved http://wwwcnkinet
55 1 : 43 [4 6 ] Janicke Pt/ 2Al 2 O 3 113 [5 ] 011 0112 MPa, 30 170,, 310 10 5 110 10 6 h - 1, 3 % / 15 %(mol) GC8810, 1 111 1 10 %, 2 min - 1 350,, 4 h, H 2, 2 1 118 10-4 218 10-4 m 5A, 1 m ; Ar, 40 ml min - 1 ; 30, 70, 100 ma,, ( GHSV) : GHSV = / ( ) 2 Fig11 Schematic diagram of experimental flow 1 feed gas ; 2 pressure gauge ; 3 mass flow controller ; 4 desiccator ; 5 regulating valve ; 6 reactor ; 7 heater ; 8 three2way valve ; 9 GC8810 gas chromatograph 211 3 H 2,, 2 Fig13 Effect of H 2 concentration vs H 2 conversion Fig12 Schematic of reactor T thermocouples ; P pressure transducer ( GHSV = 810 10 5 h - 1 ) calculation ; 77 ; 88F ; 97 Length of reaction zone/ m Tabel 1 Parameters of reactor Height of reaction zone/ m Width of reaction zone / m Amount of support / mg Amount of Pt / mg 0102 150 0102 813 118 4 10 6 h - 1 (5 % 8 %),,,, H 2 8 % 112 (mol) 150, 90 % 2 5 20 150, 2Al 2 O 3, 5 m Pt 5, 1994-2006 China Academic Journal Electronic Publishing House All rights reserved http://wwwcnkinet
44 2004 1 Fig14 Effect of reaction temperature vs H 2 conversion ( GHSV = 110 10 6 h - 1 ) H 2 mole fraction : 10 % ; 8 % ; 5 % ; calculation,,,, 2,, 212 2,, 2 %,, Fig15 Effect of reaction temperature vs H 2 conversion (H 2 mole fraction = 8 %) GHSV/ h - 1 : 313 10 5 ; 615 10 5 ; 918 10 5 ; calculation Table 2 Pressure drop of reactor GHSV 10-4 / h - 1 ( p in - p out ) in / % 9813 1180 8715 1163 7616 1156 6518 1139 4411 1113 3313 1105 213 7 8,,, ;,,, 2,,,,,,, 6,,, 3 6,, p - 1 Fig16 Effect of space velocity vs H 2 conversion (H 2 mole fraction = 8 %) 100 ; 60 ; calculation Fig17 Effect of GHSV on gas temperature profile (H 2 mole fraction = 8 %) GHSV/ h - 1 : 918 10 5 ; 615 10 5 ; 313 10 5 reactor control temperature/ : 100 ; 60 1994-2006 China Academic Journal Electronic Publishing House All rights reserved http://wwwcnkinet
55 1 : 45 Fig18 Effect of feed concentration on gas temperature profile( GHSV = 810 10 5 h - 1 ) H 2 mole concentration : 10 % ; 8 % ; 5 % reactor control temperature/ : 100 ; 80, k 1, K 1 H 2, K 2 O 2, 3 311,, (DSS) 2S ; ( DSS = Re 100), ( y E i - y S i) 2 (4) i =1, ; ; i ; y i, ; ( < 200 ; S E ), Pe 1000, [ 7] 312 u z 5 m i 5z = 5 ( u z ) 5z = 0 (1) = 5 5 x D 5 m i i 5 x p RT ( m i / M i ) - 1 i m i = m i0 u z = u 0 ( x), z = 0 ; i = 1, 2, 3 H 2 O 2 H 2 O D i 5 m i 5 x = M i r i u z = 0, x = 0 (2) (3) 5 m i K, 0152 %Pt/ SiO 2 D i = 0 u 5 x z = 0, x = H 715 kj mol - 1, x, z 4,, H B, F B = 0105, B 313 H Ikeda H 2 / Air Pt, 1 % 15 %(mol) H 2, ;, [2 ], 3 ( A B C) r H2 = r H2 = r H2 = k 1 C 015 H 2 C O2 (1 + K 1 C H2 + K 2 C O2 ) (A) k 1 C H2 C O2 (1 + K 1 C H2 + K 2 C O2 ) 3 (B) k 1 C H2 C O2 (1 + K 1 C H2 + K 2 C O2 ) 2 (C) Table 3 Estimated kinetic parameters Parameters A B C k 0 / mol - 1 g - 1 s - 1 016 013 0119 (m - 3 ) 2 E 1 / kj mol - 1 1712 13105 11133 H 1 / kj mol - 1 10147 19180 3124 H 2 / kj mol - 1 33159 37148 2310 K 0,1 / mol m - 3 K 0,2 / mol m - 3 2197 10-6 1161 10-4 010893 3155 10-7 110 10-8 2130 10-5 DSS 010029 010023 010026 MATLAB SQP, 3 Boudart [8 ] 273 373 1994-2006 China Academic Journal Electronic Publishing House All rights reserved http://wwwcnkinet
46 2004 1 Fig19 Comparison of experimental outlet H 2 Statistic concentration with simulating Table 4 Statistical test of model Model A B C 87 87 87 M 6 6 6 U 01043 8 01042 7 01043 7 Q 01002 9 01002 3 01002 6 L 01039 5 01039 5 01039 5 01962 5 01970 5 01966 7 F 201 248 225 F 0105 ( M, - M - 1) 2121 2121 2121 F 0101 ( M, - M - 1) 3104 3104 3104 ote : test number, U = i = 1 U sum of squares of regression ; Q ( y - y^ i) 2 ; M argument numbers ; sum of squares of residual error, Q = ( y i - y^ i) 2 ; L total sum of squares, L = ( y i - y i ) 2 ; i = 1 i = 1 U/ M correlation, = 1 - Q/ L ; F variance test, F = Q/ ( - M - 1) p, kpa 314 R, J mol - 1 K - 1 r i i, mol g - 1 s - 1 9 3 4 T, K u z,, y, kg m - 3, 2 Pt, g m - 2 5 6 E, S,, References ;,, 3,, H 2 4 (1), (2) /, 150 110 10 6 h - 1 H 2 8 %(mol), 90 %, (3) C i i, mol m - 3 D i i, kg m - 2 E, kj mol - 1 H, kj mol - 1 s - 1 K i i, mol m - 3 k, mol - 1 g - 1 s - 1 (m - 3 ) 2 M M i i, kg mol - 1 m i i 1 Jensen K F Microchemical Systems : Status, Challenges, and Opportunities AIChE J, 1999, 45 (10) : 2051 2054 2 Hsing I M, Srinivasan R, Harold M P, Jensen K F, Schmidt MA Simulation of Micromachined Chemical Reactors for Heterogeneous Partial Oxidation Reactions Chem Eng Sci, 2000, 55 : 3 13 3 Ikeda H, Sato J, Williams F A Surface Kinetics for Catalytic Combustion of Hydrogen2air Mixtures on Platinum at Atmospheric 1994-2006 China Academic Journal Electronic Publishing House All rights reserved http://wwwcnkinet
55 1 : 47 Pressure in Stagnation flows Surface Science, 1995, 326 : 11 26 4 Gotz Veser Experimental and Theoretical Investigation of H 2 Oxidation in a High2temperature Catalytic Microreactor Chem Eng Sci, 2001, 56 : 1265 1273 5 Janicke M T, Kestenbaum H, Hagendorf U, Sch th F, Fichtner M, Schubert K The Controlled Oxidation of Hydrogen from an Explosion Mixture of Gases Using a Microstructured Reactor/ Heat Exchange and Pt/ Al 2 O 3 Catalyst Journal of Catalysis, 2000, 191 : 282 293 6 Chen Guangwen, Li Shulian, Yuan Quan Microchannel Reactors for Methanol Autothermal Reforming Reaction Chinese Journal of Catalysis 2002, 23 : 491 492 7 Yang Yongrong ( ), Cao Bin ( ) Two2dimensional Modeling of 1,22Dichloroethane Cracking Tubular Reactor Journal of Chemical Industry and Engineering ( China) ( ), 2002, 53 : 1046 1050 8 Hanson V F, Boudart M The Reaction Between H 2 and O 2 Over Supported Platinum Catalysts Journal of Catalysis, 1978, 53 : 56 67 2004 1 ( ) : 4,4 - / TiO 2 1,3 - RFCC i Co Mn Zn 11-1994-2006 China Academic Journal Electronic Publishing House All rights reserved http://wwwcnkinet