Modifikasi gugus aktif suatu karbon aktif dan karakterisasinya
DOI:
https://doi.org/10.5614/jtki.2004.3.1.6Abstrak
The effect of addition of oxidizing acid on activated carbon surface chemistry is presented in this paper. The Activated carbon used in this study was made from coconut shell. In present study, sulfuric acid was used as the oxidizing acid. In treatment process, activated carbon was impregnated in sulfuric acid solution at various concentrations and temperature for 4 h. Subsequently, the surface chemistry of activated carbon was analyzed by Boehm titration method. From the experimental results it was found that acid functional group in activated carbon increase while the base functional group decreases. In order to know the effect of oxidizing acid on the pore structure of activated carbon, the XRD analyzed were carried out. It was found that oxidizing acid gave no effect on the pore structure of activated carbon studied. The gas phase benzen adsorption experiments were also carried out in order to find the effect of oxidizing acid on activated carbon adsorption capacity.Key Words: Activated Carbon, Base Functional Group, Acid Functional Group
Abstrak
Makalah ini mempelajari tentang pengaruh penambahan asam oksidator terhadap sifat kimia permukaan suatu karbon aktif. Karbon aktif yang digunakan adalah karbon aktif yang terbuat dari tempurung kelapa. Pada percobaan ini, karbon aktif ditreatment dengan menggunakan oksidator asam sulfat. Proses treatment dilakukan dengan merendam karbon dalam asam sulfat pada konsentrasi dan temperatur tertentu selama empat jam. Setelah proses treatment, dianalisa sifat kimia permukaan karbon aktif dengan menggunakan metode Boehm untuk menganalisa gugus asam, dimana karbon direndam dengan larutan basa dan dititrasi balik dengan larutan asam. Sedangkan untuk analisa gugus basa, karbon direndam dengan larutan asam dan dititrasi balik dengan larutan basa. Dari hasil analisa diketahui bahwa penambahan oksidator asam sulfat memperbanyak jumlah gugus asam dan mengurangi jumlah gugus basa pada permukaan karbon aktif. Untuk mengetahui perubahan struktur pori karbon aktif, dilakukan analisa dengan menggunakan X Ray Diffraction (XRD). Dari kurva hasil analisa XRD, dapat dilihat bahwa penambahan oksidator asam sulfat tidak mempengaruhi bentuk dan ukuran pori dari karbon aktif. Analisa kemampuan penyerapan karbon aktif dilakukan melalui adsorpsi benzen pada fase gas. Dari hasil percobaan diketahui bahwa penambahan oksidator asam sulfat mengurangi kemampuan penyerapan karbon aktif terhadap benzen.
Kata Kunci: Karbon Aktif, Gugus Basa, Gugus Asam
Referensi
Abassi, W.A. and Streat, M., 1994, "Adsorption of uranium from aqueous solution using activated carbon", Separ. Sci. Technol., 29, 1217.
Boehm, H.P., 2002 "Surface oxides on carbon and their critical assessment", Carbon, 40, 145-149.
Gil, A.; Puente, G., de la; Grange, P.,1997, "Evidence of textural modification of an activated carbon on liquid phase oxidation treatment", Microporous Mater., 12, 51.
Ismadji, S., & Bhatia, S.K., "Characterization of activated carbons using liquid phase adsorption", Carbon 39(2001), 1237-1250.
Jiang, Z., Liu, Y., Sun, X., Tian, Sun, F., Liang, C., You, W., Han, C., & Li, C., "Activated carbon chemically modified by concentrated H2S04 for the adsorpsion of the pollutants from wastewater and the dibenzothiopene from fuel oils", Langmuir 19 (2003), 731-736.
Moreno-Castilla, C.; Lopez-Ramon, M. V.; Carrasco-Marin, F., 2000, "Change of surface chemistry of activated carbons by wet oxidation" Carbon, 38, 1995.
Smith, M. B., "Organic Synthesis", 2"d ed., 2002, McGraw Hill, Singapore.
