Sustainable microcrystalline cellulose-based activated carbons for a greener carbon capture at post-combustion conditions

Greener carbon capture using microwave heating for the development of cellulose-based adsorbents

“…ACs were produced in a two-stage procedure involving carbonisation, where the MCC was converted into biochar, and then activation. Biochars were obtained from carbonisation at 500°C as described in our previous work [11].…”

“…Initial heating tests in the activation apparatus were conducted to ensure that the material could reach the pre-set temperature under MW irradiation. Heating tests were initially performed with the aim of directly replicating the experimental conditions (activation temperature of 600 °C) used to prepare the conventionally-prepared, MCC-based ACs by Biti et al [11]. Hence, a temperature set point of 600°C, heating rate of 10 °C/min and an inert gas flow rate of 80 NmL/min N2 were all targeted for replication in these experiments.…”

“…Maximising the production viability can be achieved by adjusting key experimental parameters such as the activating agent used, the activation temperature and duration. For instance, in our previous work ACs from microcrystalline cellulose (MCC) were produced using moderate activation temperature (600°C) and activation burn-offs of up to 30 wt % as part of improving the process feasibility [11]. Another key point of consideration for the improvement of the process efficiency is using an alternative, more efficient heating source.…”

“…This study thus aims at capitalising on the potential of MW heating, through expanding on the work by Biti et al, where promising ACs produced by physical activation were successfully reported using microcrystalline cellulose (MCC) as a feedstock [11]. MCC is a generally attractive renewable feedstock for various commercial applications because it possesses beneficial mechanical properties such as high strength and stiffness [16].…”

“…Whilst lignocellulosic feedstocks such as those previously mentioned could be used in their waste form for AC production, the access of these feedstocks individually are more limited by their geographical abundance. Considering the abundance of cellulose, and the abundance of MCC in various waste forms, MCC is a feedstock with greater global accessibility, which is more appropriate to the global challenge of the need for sustainable sorbent production for post-combustion capture [11]. Also, considering the scale of some of the source materials of MCC such oil palm waste, it is worth investigating whether the potential exists for the development of MCC-based sorbents for post-combustion carbon capture.…”