Catalytic partial oxidation of gasoline to syngas in a dense membrane reactor

In our previous work, it was shown that LiLaNiO/gamma-Al2O3 was an excellent catalyst for partial oxidation of heptane to syngas in a fixed-bed reactor at high temperature and the selectivity of CO was about 93%. However, pure oxygen was used as the oxidant. We have developed a dense oxygen permeation membrane Ba0.5Sr0.5Co0.8Fe0.2O3 that can supply pure oxygen for the reaction. In this work, the membrane was combined with the catalyst LiLaNiO/gamma-Al2O3 in one rector for the partial oxidation of heptane that is typical component of gasoline. A good performance of the membrane reactor has been obtained, with 100% n-heptane conversion and >94% hydrogen selectivity at the optimized reaction conditions. (C) 2004 Elsevier B.V. All rights reserved.

The effects of CO2 addition on the partial oxidation of heptane for hydrogen generation

The effects of CO2 on the partial oxidation of heptane for hydrogen generation have been studied. Based on the experimental results and thermodynamic equilibrium calculations, the validity of CO2 addition to weaken the hot spots, and the feasibility of the autothermal operation are discussed.

Catalytic partial oxidation of n-heptane for hydrogen production

Partial oxidation of n-heptane (POH) for hydrogen generation was studied over several catalysts between 700 and 850degreesC. Modified Ni-based/gamma-Al2O3 catalyst exhibited not only good catalytic activity but also good carbon deposition resistance ability. Under the modified reaction conditions, 100% n-heptane conversion and 93% hydrogen selectivity can be obtained.

SbOx/SiO2 catalysts for the selective oxidation of methane to formaldehyde using molecular oxygen as oxidant

SbOx and SbOx/SiO2 catalysts were prepared and investigated for methane selective oxidation to HCHO. HCHO selectivity up to 41% can be obtained on Sb2O5/SiO2 catalyst at 873 K and just drop gently to 18% with temperature up to 923 K. HCHO selectivity for SbOx/SiO2 catalysts decreases gently with reaction temperature, so considerable value of HCHO selectivity can still be obtained at high temperatures.

Partial oxidation of ethane to syngas in an oxygen-permeable membrane reactor

A perovskite-type oxide of Ba0.5Sr0.5Co0.8Fe0.2O3-delta (BSCFO) with mixed electronic and oxygen ionic conductivity at high temperatures was used as an oxygen-permeable membrane. A tubular membrane of BSCFO made by extrusion method has been used in the membrane reactor to exclusively transport oxygen for the partial oxidation of ethane (POE) to syngas with catalyst of LiLaNiO/gamma-Al2O3 at temperatures of 800-900 degreesC. After only 30 min POE reaction in the membrane reactor, the oxygen permeation flux reached at 8.2 ml cm(-2) min(-1). After that, the oxygen permeation flux increased slowly and it took 12 h to reach at 11.0 ml cm(-2) min(-1). SEM and EDS analysis showed that Sr and Ba segregations occurred on the used membrane surface exposed to air while Co slightly enriched on the membrane surface exposed to ethane. The oxygen permeation flux increased with increasing of concentration of C2H6, which was attributed to increasing of the driving force resulting from the more reducing conditions produced with an increase of concentration of C2H6 in the feed gas. The tubular membrane reactor was successfully operated for POE reaction at 875 degreesC for more than 100 h without failure, with ethane conversion of similar to 100%, CO selectivity of >91% and oxygen permeation fluxes of 10-11 ml cm(-2) min(-1). (C) 2002 Elsevier Science B.V. All rights reserved.

Partial oxidation of ethane to syngas over nickel-based catalysts modified by alkali metal oxide and rare earth metal oxide

The catalytic activity, thermal stability and carbon deposition of various modified NiO/gamma-Al2O3 and unmodified NiO/gamma-Al2O3 catalysts were investigated with a flow reactor, XRD, TG and UVRRS analysis. The activity and selectivity of the NiO/gamma-Al2O3 catalyst showed little difference from those of the modified nickel-based catalysts. However, modification with alkali metal oxide (Li, Na, K) and rare earth metal oxide (La, Ce, Y, Sm) can improve the thermal stability of the NiO/gamma-Al2O3 and enhance its ability to suppress carbon deposition during the partial oxidation of ethane (POE). The carbon deposition contains graphite-like species that were detected by UVRRS. The nickel-based catalysts modified by alkali metal oxide and rare earth metal oxide have excellent catalytic activities (C2H6 conversion of similar to 100%, CO selectivity of similar to 94%, 7x 10(4) l/(kg h), 1123 K), good thermal stability and carbon-deposition resistance.