Volume 3, Issue 2, Pages 334-347 (August 2017) Bifunctional Catalysts for One-Step Conversion of Syngas into Aromatics with Excellent Selectivity and Stability  Kang Cheng, Wei Zhou, Jincan Kang, Shun He, Shulin Shi, Qinghong Zhang, Yang Pan, Wu Wen, Ye Wang  Chem  Volume 3, Issue 2, Pages 334-347 (August 2017) DOI: 10.1016/j.chempr.2017.05.007 Copyright © 2017 Elsevier Inc. Terms and Conditions

Chem 2017 3, 334-347DOI: (10.1016/j.chempr.2017.05.007) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 1 Effect of Temperature on Catalytic Performance (A) Zn–ZrO2 for syngas conversion. (B) Zn–ZrO2/ZSM-5 for syngas conversion. Reaction conditions: catalyst weight, 0.10 g for Zn–ZrO2 and 0.30 g for Zn–ZrO2/H-ZSM-5; 573–723 K; H2/CO, 2:1; 3 MPa; 25 cm3 min−1. Selectivity was calculated on a molar carbon basis for CO hydrogenation. Black arrows denote CO conversion. See Table S3 for detailed product distributions. The formation of CO2 by the WGS reaction is also shown in Table S3. Chem 2017 3, 334-347DOI: (10.1016/j.chempr.2017.05.007) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 2 Effect of Contact Time on Catalytic Performance (A) Zn–ZrO2 for syngas conversion. (B) Zn–ZrO2/H-ZSM-5 for syngas conversion. (C) Reaction scheme over the bifunctional catalyst. Reaction conditions: catalyst weight, 0.010–3.0 g; 673 K; H2/CO, 2:1; 3 MPa; 25 cm3 min−1. The selectivity was calculated on a molar carbon basis for CO hydrogenation. Black arrows denote CO conversion. See Table S4 for detailed product distributions. The formation of CO2 by the WGS reaction is also shown in Table S4. Chem 2017 3, 334-347DOI: (10.1016/j.chempr.2017.05.007) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 3 Effect of Key Catalyst Factors on the Performance of Bifunctional Catalysts (A) Zn/Zr molar ratio. (B) ZrO2/H-ZSM-5 with different densities of strong acid sites. Reaction conditions: catalyst weight 1.0 g; 703 K; H2/CO, 2:1; 3 MPa; 25 cm3 min−1. C5+ denotes aliphatic hydrocarbons with carbon numbers ≥5. Selectivity was calculated on a molar carbon basis for CO hydrogenation. The formation of CO2 by the WGS reaction also occurred and the selectivity of CO2 was in the range of 38%–42% over these catalysts. Black arrows denote CO conversion. Chem 2017 3, 334-347DOI: (10.1016/j.chempr.2017.05.007) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 4 Effect of the Proximity of the Two Components (A) (i) Dual bed (0.33 g Zn–ZrO2 + 0.67 g H-ZSM-5); (ii) mixing of granules of two components with sizes of 250–600 μm; (iii) Zn–ZrO2 nanoparticles dispersed on micrometer-sized H-ZSM-5 crystallites; (iv) nanocomposites of Zn–ZrO2 and H-ZSM-5. Reaction conditions: catalyst weight 1.0 g; 673 K; H2/CO, 2:1; 3 MPa; 25 cm3 min−1. (B) Scanning electron microscopy images for the sample with Zn–ZrO2 nanoparticles dispersed on micrometer-sized H-ZSM-5 crystallites. Scale bar, 1 μm. (C) Transmission electron microscopy images for the nanocomposite of Zn–ZrO2 and H-ZSM-5. Scale bar, 50 nm. Chem 2017 3, 334-347DOI: (10.1016/j.chempr.2017.05.007) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 5 Stability of the Zn–ZrO2/H-ZSM-5 Catalyst Reaction conditions: catalyst weight 3.0 g; 673 K; H2/CO, 2:1; 3 MPa; 25 cm3 min−1. Chem 2017 3, 334-347DOI: (10.1016/j.chempr.2017.05.007) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 6 Tuning the BTX Fraction in Aromatics by Silylation of H-ZSM-5 with TEOS (A) Fractions of products in aromatics. Reaction conditions: catalyst weight 1.0 g; 703 K; H2/CO, 2:1; 3 MPa; 25 cm3 min−1. See also Table S8. (B) 2,6-DTBPy-adsorbed FT-IR. (C) Scheme for suppressing the formation of heavier aromatics by selective silylation of external Brønsted acidity. Chem 2017 3, 334-347DOI: (10.1016/j.chempr.2017.05.007) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 7 Effect of CO on Methanol Conversion over the Zn–ZrO2/H-ZSM-5 Catalyst (A) Effect of CO on product selectivity in methanol conversion. (B) Functioning mechanism of CO. (C) Incorporation of 13C into toluene during the conversion of CH3OH under 13CO. Catalytic reactions were performed at 673 K with 100% CH3OH conversion in each case. Experimental details are shown in Supplemental Information. Chem 2017 3, 334-347DOI: (10.1016/j.chempr.2017.05.007) Copyright © 2017 Elsevier Inc. Terms and Conditions

Scheme 1 Typical Reaction Processes Related to Syngas Chemistry The red-line route demonstrates our SMA process for the direct synthesis of aromatics via reaction coupling. Chem 2017 3, 334-347DOI: (10.1016/j.chempr.2017.05.007) Copyright © 2017 Elsevier Inc. Terms and Conditions