This article provides results of the usability of baobab fruit shell to produce activated carbons by chemical activation using ZnCl2, H3PO4, and KOH. This study indicated that activated carbon produced from baobab fruit shell fruit can be used as a promising adsorbent for the removal of methylene blue from aqueous solutions. Significant changes on the material surface following the activation process were observed through SEM and FTIR analyses. Scanning electron micrographs of BFS-ACs showed that porous structures were formed during activation, while the FTIR results indicated that the carbons have abundant functional groups on the surface. KOH activation led an activated carbon with a high methylene blue adsorption of 95.54% and maximum adsorption capacity of 113.63 mg/g, which is directly related to the specific surface area of activated carbons. The adsorption isotherm data were fitted to Langmuir and Freundlich adsorption models. The Langmuir isotherm model showed better fit to the equilibrium data than the Freundlich model. The adsorption process was well described by the pseudo-second-order kinetics. The BFS-ACs is an effective and low-cost adsorbent for the removal of MB from an aqueous solution. ABSTRAK: Kajian ini memberi input tentang kebolehgunaan kulit buah baobab bagi menghasilkan karbon teraktifan melalui aktiviti kimia menggunakan ZnCl2, H3PO4, dan KOH. Karbon aktif daripada kulit buah Baobab ini berpotensi sebagai penyerap bagi menyingkir larutan akueus metilin biru. Perubahan ketara pada permukaan bahan diikuti dengan proses pengaktifan dipantau melalui analisis SEM dan FTIR. Imbasan elektron mikrograf BFS-AC menunjukkan struktur porus terhasil semasa proses pengaktifan. Sementara dapatan FTIR menunjukkan karbon mempunyai banyak kumpulan berfungsi pada permukaan. Pengaktifan KOH menghasilkan karbon aktif menggunakan larutan biru metilin yang tinggi sebanyak 95.54% dan kapasiti maksimum penyerapan 113.63 mg/g, iaitu berkadar langsung dengan tumpuan kawasan permukaan karbon aktif berkaitan. Data isoterma penyerapan dibina pada model penyerapan Langmuir dan Freundlich. Model isoterma Langmuir lebih padan pada data keseimbangan berbanding model Freundlich. Proses penyerapan menunjukkan lebih kinetik order-kedua-pseudo. BFS-AC sangat efektif dan penyerap murah bagi membuang MB daripada larutan akues.

Chemical agents have a good influence on the formation of activated carbons, surface characteristic, and its adsorption properties. In this study, the effect of activating agents (ZnCl2, KOH, and H3PO4) on baobab fruit shell (BFS) were evaluated. The characteristics of the baobab fruit shell based activated carbon (BF-ACs) were evaluated through the yield and iodine number. BF-ACs were also characterized by Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), and nitrogen (N2) adsorption. SEM analysis illustrates those porous structures formed on the surface of BF-ACs were with different sizes. The XRD analysis show that the main structures of BF-ACs are amorphous. FT-IR data demonstrates the presence of different surface groups on the produced BF-ACs. Among activating agent, the KOH was observed to the most appropriate for the production of activated carbon with a large surface area (1029.44 m2/g) from baobab fruit shell.

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Baobab fruit shell (BFS) biomass was used as an alternative precursor for producing high surface area and microporous baobab fruit shell activated carbon (BFS-AC) by chemical activation using KOH. Scanning electron microscope (SEM) was performed for the characterization of baobab fruit shell activated carbon. The adsorption property of BFS-AC for the removal of phenol from aqueous solution was evaluated. The effect of key adsorption parameters such as the contact time (10-20 min), BFS-AC dose (2.5-3.5 g/L), pH (1-3), and agitation speed (150-250 rpm) were optimized using a response surface methodology (RSM) with faced centered central composite design (FCCCD). Consequently, a maximum adsorption capacity (196.86 mg/g) was achieved at 15 min of contact time, 2 of pH, 3 g/L of adsorbent dosage, and 250 rpm of agitation speed. The results reveal that BFS-AC has an efficient performance for the removal of phenol from aqueous media.

Activated carbons (ACs) were produced from baobab fruit shell (BFS) by varying the operating parameters of activation temperatures, activation times, and impregnation ratios using response surface methodology (RSM). Adsorption tests on an aqueous solution of phenol were used to determine the optimum conditions for BF-ACs produced and central composite design (CCD) was used to determine the effects of the three preparation variables on the adsorption capacity of phenol. Based on the CCD, a quadratic equation was developed for the response, and from the analysis of variance (ANOVA), the most significant factor was specified. The results demonstrated that the optimal activated carbon which had the highest phenol adsorption capacity (93.56 mg/g) was obtained by these conditions as follows: the activation temperature of 700 °C, the activation time of 60 min, and IR of 2. Characterisation of the BF-AC produced showed that good quality adsorbents with the few functional groups and the distribution of the well-forming pores are found during the optimum production conditions. The highest BET surface area and micropore volume were 1263.127 m2/g and 0.453 cm3/g, respectively. It concluded that activated carbons produced from baobab fruit shells using KOH are suitable for the treatment of wastewaters from organic pollutants.