Abstract:
Low steam-to-carbon ratio dry reforming of methane is a potential route for simultaneously achieving emission reduction and syngas production. However, the strong coupling among the reactions and the high risk of carbon deposition in this system make it difficult to simultaneously optimize methane conversion, syngas composition, and carbon deposition. To optimize the operating conditions of low steam-to-carbon ratio methane dry reforming , a fixed-bed experimental setup was used to investigate the effects of key factors such as reforming temperature (
T),
n(CO
2)∶
n(CH
4),
n(H
2O)∶
n(CH
4), and total inlet flow rate (
QV) on methane conversion (
XCH4) and the
n(H
2)∶
n(CO) . Based on single-factor screening ,
QV was fixed at 3 L·min
−1, and a Box–Behnken design was employed to establish a response surface model for multi-factor coupling analysis and operating-condition optimization. The catalyst under the optimal conditions was further characterized by temperature-programmed oxidation coupled with mass spectrometry (O
2-TPO-MS). The results show that increasing
T,
n(CO
2)∶
n(CH
4), and
n(H
2O)∶
n(CH
4) enhance
XCH4, while increasing
QV reduce
XCH4. At
T=
1000 °C, CH
4 =1 L·min
−1、H
2O =1 L·min
−1、CO
2 =1 L·min
−1,
XCH4reach a maximum of 96%,while the
n(H
2)∶
n(CO) is approximately 1. Under the optimal conditions, the carbon deposition amount is determined to be 1.59 mg·g
−1, and the deposited carbon is dominated by relatively easy-to-oxidize carbon species. These results provide a reference for subsequent reactor development and carbon suppression strategies in low steam-to-carbon ratio methane dry reforming.