Kinetics of Hydrogen Production of Methanol Reformation Using Cu/ZnO/Al₂O₃ Catalyst

Abstract

The catalytic performance of methanol reformation using Cu/ZnO/Al2O3 was investigated at low temperature. The operation conditions, such as composition of Cu, Zn, and Al, temperature, molar ratio of H2O/CH3OH, weight hourly space velocity, catalyst weight, and kind and flow rate of carrier gas (helium and air), were evaluated to obtain the optimum reaction condition. The catalysts were prepared by oxalic coprecipitation, coprecipitation, and polyol method. The weight composition of Cu, Zn, and Al prepared by oxalic coprecipitation was 15:15:5 by high-throughput screening of combinatorial chemistry method, which was the best Cu/ZnO/Al2O3 catalyst. The prepared catalysts showed high activity and selectivity towards hydrogen formation. The methanol conversion, production rate, and volumetric percentage of hydrogen using this best catalyst were larger than 95%, 0.65 mol/h x g and 59%, respectively, and the CO volumetric percentage was smaller than 0.22% when the reaction temperature was 240 degrees C. The size and dispersity of copper, and the activity and turnover frequency of the catalyst were calculated as well.

Stability of bimetallic Pd–Zn catalysts for the steam reforming of methanol

“…The TOF was estimated to be 0.39 s -1 , which is comparable to the value of 0.8 s -1 reported in the literature for Pd/ZnO catalysts [25]. As a comparison, the TOF for Cu/ZnO/Al 2 O 3 catalysts reported in the literature has been reported to range from 0.0152 s -1 [26] to 0.11 s -1 [27]. After Table 2: Reactivity comparison of two catalysts exposed to different pretreatments prior to steam reforming conditions The TOF was estimated to be 0.39 s -1 , which is comparable to the value of 0.8 s -1 reported in the literature for Pd/ZnO catalysts [25].…”

Cu/ZnO/Al2O3/Cr2O3/CeO2 Catalyst for Hydrogen Production by Oxidative Methanol Reforming via Washcoat Catalyst Preparation in Microchannel Reactor

“…The preparation of catalysts was reported in our previous study [7,8,9]. Catalyst-precursor solutions were prepared by adding Cu(NO3)2.2.5H2O(s) (11.7 g), Zn(NO3)2.6H2O(s) (11.7 g), Al(NO3)3.9H2O(s) (2.56 g), C r ( N O 3 ) 2 .…”

“…Next, 0.1 g of sample was placed in a quartz fixed bed reactor, and 30 mL/min a high-purity flow of 10 vol% H2-Ar mixtures (TPR) was passed through the bed. The temperature of sample was raised at a rate of 5 o C/min from 30 o C up to 400 o C and the composition of hydrogen was monitored by means of TCD cell in GC (Shimadzu 8A) and the results were recorded with a computer [7].…”

Thermal Behavior and Hydrogen Production of Methanol Autothermal Reforming Performed Using Oxygen Enrichment and Cu/ZnO/Al2O3/Cr2O3/CeO2 Catalyst

“…The preparation of catalysts was reported in our previous study [7,18,19]. Catalystprecursor solutions were prepared by adding Cu(NO3)2.2.5H2O(s) (11.7 g), Zn(NO3)2.6H2O(s) (11.7 g), Al(NO3)3.9H2O(s) (2.56 g), Cr(NO3)2.6H2O(s) (0.43 g), and Ce(NO3)3.6H2O(s) (0.90 g) into flasks containing ethanol (100 ml, -5 °C), and the solutions were stirred until the compounds dissolved.…”

“…The experimental apparatus used was described in our previous work [19]. First, the Cu/ZnO/Al2O3/Cr2O3/CeO2 catalysts were prepared as mentioned in Section 2.2.…”