Unravelling the Potency of Activated Carbon Powder Derived from Cultivated Marine Microalgae as a Promising Filler in Mixed Matrix Membranes

Abstract

Activated carbon-filled mixed matrix membranes were commonly used to enhance the separation performance of liquid or gas separation processes. Activated carbon is traditionally derived from agricultural crops such as coconut shells or wood biomass. Marine microalgae however have a great potential to produce powdered activated carbon. In this study, marine microalgae Chlorella vulgaris have been evaluated for their carbon content, and the 16.09% carbon content has potential to be employed as a raw material in manufacturing activated carbon powder. Dry microalgae were carbonized at a temperature of 500 °C for 30 min, at a constant increment rate of temperature of 10 °C per minute to produce microalgae charcoal. Chemically-based activation treatments using H3PO4 and ZnCl2 with concentrations of 10%, 30%, and 50%, respectively, assisted by microwave irradiation, have been used to prepare activated carbon. The properties of activated carbon powder were analyzed including yields, ash content, volatile substances, pure activated carbon content, absorption of iodine solution, surface area, and imaging of activated carbon using SEM-EDX. The best treatment characteristics were obtained using H3PO4 at a concentration of 50% with characteristics of 19.47% yield, 11.19% ash content, 31.92% volatile content, 56.89% pure activated carbon, 325.17 mg g−1 iodine absorption, and 109.273 m2 g−1 surface area based on the Brunauer–Emmett–Teller (BET) method, as well as a 5.5-nm average pore diameter. The SEM-EDX imaging results showed the formation of micropores on the surface of activated carbon, with carbon content reaching 72.31%; however, impurities could decrease the surface area and reduce the absorption performance of microalgae activated carbon.

Refining micropore capacity of activated carbon derived from coconut shell via deashing post-treatment

“…The increase of ash content of the activated carbon was caused by the oxidation reaction during the physical activation, which reduced the adsorption capabilities. This is mainly due to pores clogged by various minerals including Ca and K. The deposition of minerals on the surface of activated carbon was also reported by Sukoyo et al (2019). As noted by Husillos Rodríguez et al (2016), the largest components found in activated carbon ash were Si, Fe, and S. The EDXRF result reveals that distilled water post treatment decreased the ash forming elements including Fe, K, and Ca.…”

Activated Carbon Loaded Mixed Matrix Membranes Extracted from Oil Palm Empty Fruit Bunches for Vehicle Exhaust Gas Adsorbers

“…and its absorption of iodine was used for the synthesis of nano-activated carbon 19) . This synthesis was carried out by chemical activation assisted by ultrasonic waves with a frequency of 28 KHz for 45 minutes, then allowed to stand for 24 hours at room temperature and filtered.…”

Preparation of Activated Carbon from Local Biowaste as Fillers for Mixed Matrix Membranes

“…Commercial activated carbon commonly derived from bituminous coal, coconut shell, and woods [13]. Recent studies reported the manufacture of activated carbon from other biomass source, such as oil palm empty fruit bunch [14,15], palm shell [16], langsat (Lansium domesticum) empty fruit bunch waste [17], coconut leaves [18], pine cone shell [19] and microalgae [20]. Most of the studies reveals the potency of agricultural biowaste as activated carbon sources.…”