Pembuatan dan Karakterisasi Karbon Aktif Batok Kelapa dengan Aktivator Kalium Hidroksida dan Magnesium Hidroksida
RIDHAR RAHMAN FITRIADI, Robertus Dhimas Dhewangga Putra, S.T., M.Eng., Ph.D.
2024 | Skripsi | TEKNIK MESIN
The depletion of fossil fuel reserves and increasing emissions mean that humans need to think about creating new, renewable energy for sustainable living. Hydrogen energy is considered as a new renewable energy and clean energy that has high gravimetric energy density compared to fossil fuel energy. But the disadvantage, hydrogen has a very low volumetric energy density. Thus, one of the main challange hydrogen energy is its storage. While the common storage systems, compressed gas at 700 bar and liquefaction at -253 C, require substantial energy to process. Hydrogen storage developments have been carried out, one of which is activated carbon-based adsorption as an adsorbent. This research aims to understand the manufacture of activated carbon, find out effect of dehydration in physical activation study the effect of activating substances on the resulting surface area, and determine the structure and morphology of activated carbon.
In this research, coconut shell was chosen as the basic material for activated carbon because of its abundant availability in Indonesia. Coconut shells are used because they have a carbon content of 74.3%. In the impregnation process, the activating agents KOH and Mg(OH)2 are used as chemical activators. Followed by the dehydration process at a temperature of 400 C for 2 hours and physical activation at a temperature of 800 C for 1 hour with argon gas flow as inert. The impregnation treatment with an activating agent is expected to control the oxidation process in carbon so that the number of micropores to mesopores increases followed by an increase in the surface area of the activated carbon.
Activated carbon with a variation of the AC/KOH ratio of 1/6 gets the highest surface area at 1802 m^2/g. Meanwhile, by varying the ratio of KOH and Mg(OH)2 activators, the surface area value is only 120.56 m^2/g. The characterization results show that the average diameter of the pores formed is ± 5 nm which is included in the mesopores. This result is supported by the SEM characteristic test, the largest pore volume was also obtained at a variation of the AC/KOH ratio of 1/6 at 1.066 cm^3/g. Test results from X-ray diffraction (XRD) shows the crystal structure of carbon in the form is amorphous. Other material characterizations carried out were proximate and Fourier Transform Infrared (FTIR) tests.
Kata Kunci : penyimpanan hidrogen, adsorpsi, impregnasi, karbon aktif, tempurung kelapa, luas permukaan