Kayu cerucuk bakau yang biasanya dianggap sebagai sisa dari tapak pembinaan boleh digunakan untuk menghasilkan karbon teraktif yang mempunyai luas permukaan yang tinggi untuk penyingkiran pewarna yang tidak terurai melalui penjerapan. Objektif utama kajian ini adalah untuk menyediakan karbon teraktifk optimum daripada kayu bakau melalui satu langkah pengaktifan kimia dengan asid fosforik menggunakan metodologi tindak balas permukaan. Kesan pembolehubah penyediaan iaitu suhu pengaktifan dan nisbah pengisitepuan H3PO4 ke pelopor pada hasil karbon teraktif dan kapasiti penjerapan pada pewarna biru metilena disiasat. Berdasarkan reka bentuk komposit berpusat, dua model kuadratik telah diterbitkan untuk mengaitkan pembolehubah penyediaan pada hasil dan kapasiti penjerapan. Faktor yang paling berpengaruh pada setiap respons rekabentuk eksperimen telah dikenal pasti melalui analisis varians. Ramalan hasil dan kapasiti penjerapan selepas proses optimisasi didapati bersetuju secara memuaskan dengan nilai-nilai eksperimen. Karbon teraktif optimum yang disediakan pada suhu pengaktifan 464oC dan nisbah pengisitepuan 1.81 memberikan hasil sebanyak 32.01%, kapasiti penjerapan biru metilena sebanyak 231.16 mg/g dan luas permukaan BET sebanyak 390.39 m2/g. Data eksperimen penjerapan berpandanan dengan isoterma Langmuir dengan nilai R2 sebanyak 0.9981. Keputusan kajian menunjukkan bahawa karbon teraktif yang disediakan daripada kayu bakau sesuai digunakan untuk penjerapan metilena biru daripada larutan akuas.
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The mangrove pile leftover which is normally considered as waste from construction site can be used to produce activated carbon with high surface area for removal of non-degradable dye via adsorption. The main objective of this research was to prepare optimum activated carbon from mangrove timber via single-step chemical activation with phosphoric acid using response surface methodology. The effects of preparation variables which were activation temperature and impregnation ratio of H3PO4 to precursor on the activated carbon yield and adsorption capacity on methylene blue dye were investigated. Based on the central composite design, two quadratic models were developed to correlate the preparation variable to the yield and adsorption capacity. From the analysis of variance, the most influential factor on each experimental design response was identified. The predicted yield and adsorption capacity after process optimization was found to agree satisfactory with the experimental values. The optimal activated carbon which was prepared at an activation temperature of 464oC and impregnation ratio of 1.81 gave yield, methylene blue adsorption capacity and BET surface area of 32.01%, 231.16 mg/g and 390.39 m2/g. The experimental data of adsorption fitted well to Langmuir isotherm with R2 of 0.9981. The results of adsorption study showed that the activated carbon prepared from mangrove timber is suitable for methylene blue removal from aqueous solution.
Preparation of activated carbon from mangrove timber via chemical activation using response surface methodology / Ng Wei Ming