Paper sludge contains papermaking mineral additives and fibers, which could be reused or recycled, thus enhancing the circularity. One of the promising technologies is the fast pyrolysis of paper sludge, which is capable of recovering > 99 wt.% of the fine minerals in the paper sludge and also affording a bio-liquid. The fine minerals (e.g., ‘circular’ CaCO3) can be reused as filler in consumer products thereby reducing the required primary resources. However, the bio-liquid has a lower quality compared to fossil fuels, and only a limited application, e.g., for heat generation, has been applied. This could be significantly improved by catalytic upgrading of the fast pyrolysis vapor, known as an ex-situ catalytic pyrolysis approach. We have recently found that a high-quality bio-oil (mainly ‘bio-based’ paraffins and low-molecular-weight aromatics, carbon yield of 21%, and HHV of 41.1 MJ kg-1) was produced (Chem. Eng. J., 420 (2021), 129714). Nevertheless, catalyst deactivation occurred after a few hours’ of reaction. As such, catalyst stability and regenerability are of research interest and also of high relevance for industrial implementation. This project aims to study the potential of the add-on catalytic upgrading step to the industrial fast pyrolysis of paper sludge process. One important performance metric for sustainable catalysis in the industry is the level of catalyst consumption (kgcat tprod-1) for catalytic pyrolysis of paper sludge. Another important research topic is to establish the correlation between yield and selectivity of the bio-chemicals and the catalyst characteristics. For this, different types of catalysts (e.g., FCC-type E-Cat) will be tested and several reaction-regeneration cycles will be performed. These studies will determine under which conditions catalytic fast pyrolysis of paper sludge is technically and economically viable.
Sustainable energy production relies on smart design of functional nanomaterials with controllable sizes and structures. Core-shell nanoparticles are highly functional materials with properties arising from the core or shell materials or a combination of both. Changing the electronic properties of the shell by tailored design or induced by the underlying core lead to enhanced catalytic performances, especially in electrocatalysis. Tailoring the structure and functions of core and shell materials simultaneously often involves complex chemical methods. In this KIEM GoChem project, University of Amsterdam will work together with VSParticle, Spark904 and Inholland University of Applied Sciences to develop a novel and environmentally friendly method for the gas-phase synthesis of core-shell nanoparticles. A physical process will be used to control the growth and the mean size of the core whilst the structure and thickness of the shell will be tuned via selective adsorption and thermal processes. Core-shell nanoparticles produced by the proposed method can be directly incorporated into the next process step, e.g. at electrode surface or in (conductive) composites.
