(417g) Renewable H2 Production from Steam Reforming of Glycerol (SRG) over Encapsulated Ni/Silicalite-1 Zeolite Supported Catalyst

Biodiesel, an environmentally friendly fuel can be produced through catalytic reaction of oil and renewable alcohols; however, biodiesel production generates glycerol as a by-product and is being treated as a waste. Therefore, developing a new route for glycerol conversion into high-added value products is an attractive method to utilize it for economic viability of biodiesel industries. As shown by Equations (1)-(3), various reactions, including SRG, glycerol decomposition and water gas shift,¹ making the system rather complex to be selective to produce H₂ can be promoted. Therefore, the aim of this work focuses on improving the catalytic activity, stability and coke-resistant Ni-based silicalite-1 catalyst by encapsulation process.

Materials and Methods

In this study, Ni-Silicalite-1 zeolite crystals were synthesized using similar approach as reported by Wang ¹. The SRG experiments were carried out at 750 ^oC for 6 h, and samples of the product gases (H₂, CO₂, CO and CH₄) were subsequently analyzed using gas chromatograph (GC, PerkinElmer, Clarus® 580) equipped with TCD and FID, respectively.

Results and Discussion

A glycerol conversion of ~ 99% was achieved for Ni/Si-1-Encapsulated catalyst, while a lower glycerol conversion of ~85 % was obtained for Ni/Si-1-impregnated between 1 – 2 h, then it dropped to ~80% for 3-6 h as shown in Figure 1. Similarly, the selectivity of H₂ (Figure 2b) was more active (~60%) and stable during the time-on-stream (TOS) as compared to Ni/Si-1-impregnated catalyst shown in Figure 2a.

Significance

The results showed that the Ni/Si-1-Encapsulated catalyst was more active and selective towards H₂ production from SRG and exhibited coke resistance ability at 750 °C.

Reference

[1] Wang N, Sun Q, Bai R, Li X, Guo G, Yu J. In Situ Confinement of Ultrasmall Pd Clusters within Nanosized Silicalite-1 Zeolite for Highly Efficient Catalysis of Hydrogen Generation. Journal of the American Chemical Society 2016;138(24):7484-7.