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Today, zeolitic catalysts play an important role in catalytic processes such as cracking, alkylation, etc. However, shaping these catalysts for industrial applications remains a challenge. Despite extensive research in this area in recent years, the number of studies is limited, and detailed information is scarce. Consequently, this study aims to increase awareness of the challenges associated with catalyst shaping and to contribute to the body of knowledge in this field. Following an introduction to the fundamental concepts and shaping techniques, our focus in this review has been on the binder agent, whereby we have categorized the effects of binders that can influence catalyst performance. We demonstrate that while binders may not necessarily possess catalytic properties, the chemical interaction between the binder and the catalyst, as well as the extrusion process, can significantly impact the physicochemical characteristics of the final catalyst, including its acid characteristics, pore characteristics, distribution of loaded metals, and so on. Moreover, depending on the desired properties of the catalyst, different sequences can be employed to utilize the binder. Finally, we identify research gaps in this domain and present recommendations for future studies. [ABSTRACT FROM AUTHOR]

In this study, a series of cobalt-based spinel ferrites catalysts, including nickel, cobalt, zinc, and copper ferrites, were synthesized using the sol–gel auto-combustion method followed by a chemical reduction process. These catalysts were employed for accelerating hydrogen generation via the sodium borohydride hydrolysis process. A continuous stirred tank reactor was used to perform catalytic reactor tests. All samples were subjected to analysis using XRD, FESEM, EDX, FTIR, and nitrogen adsorption–desorption techniques. The results revealed that the cobalt-based copper ferrite sample, Co/Cu-Ferrite, exhibited superior particle distribution, and porosity characteristics, as it achieved a high hydrogen generation rate of 2937 mL/min.gcat. In addition, the higher electrical donating property of Cu-Ferrite which leads to the increase in the electron density of the cobalt active sites can account for its superior performance towards hydrolysis of NaBH4. Using the Arrhenius equation and the zero-order reaction calculation, activation energy for the sodium borohydride hydrolysis reaction on the Co/Cu-Ferrite catalyst was determined to be 18.12 kJ/mol. This low activation energy compared to other cobalt-based spinel ferrite catalysts confirms the catalyst's superior performance as well. Additionally, the outcomes from the recycling experiments revealed a gradual decline in the catalyst's performance after each cycle during 4 repetitive cycles. The aforementioned properties render the Co/Cu-Ferrite catalyst an efficient catalyst for hydrogen generation through NaBH4 hydrolysis. [ABSTRACT FROM AUTHOR]