Karbon yang diaktifkan diperbuat daripada sekam buah pinang dengan menggunakan kaedah pengaktifan fizikal kimia yang terdiri daripada rawatan kalium hidroksida (KOH) dan penggasan karbon dioksida (CO2). Kesan dua pembolehubah berkaitan penyediaan karbon teraktif (suhu pengaktifan CO2 dan nisbah enap jerap KOH:arang) pada penjeraapan metilena biru telah dikaji. Microstruktur karbon teraktif telah dinilai berdasarkan kepada penjerapan N2 dan imbasan mikroskop electron (SEM), manakala penjerapan kinetik dinilai menggunakan pewarna biru metilena. Data eksperimen pada keseimbangan telah dianalisis menggunakan model Langmuir dan model Freundlich untuk penjerapan. Data keseimbangan menepati model Langmuir dengan kapasiti penjerapan monolapisan 576.90 mg/g. Faktor berdimensi, RL mendedahkan sifat yang menggalakkan isoterma system perwarna-karbon diaktifkan.. Kadar penjerapan telah didapati menepati kinetik pseudo-tertib-kedua. Keadaan optimum untuk menyediakan karbon teraktif daripada sekam buah pinang bagi penjerapan metilena biru didapati seperti berikut: suhu pengaktifan CO2 800°C, nisbah KOH:arang 3 dan 1211.65 m2/g untuk luas permukaan spesifik Brunauer-Emmet-Teller (BET).
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Activated carbon was prepared from Areca Catechu husk using physiochemical activation method which consisted of potassium hydroxide (KOH) treatment and carbon dioxide (CO2) gasification. The effects of two preparation variables (CO2 activation temperature and KOH:char impregnation ratio) on the methylene blue uptake and activated carbon yield were investigated. The microstructure was assessed based on N2 adsorption and scanning electron microscopy (SEM) while the adsorption kinetics was evaluated using methylene blue dye. The experimental equilibrium data were analyzed by the Langmuir and Freundlich models for adsorption. Equilibrium data fitted well with the Langmuir model with maximum monolayer adsorption capacity of 576.90 mg/g. The dimensionless factor, RL revealed the favorable nature of the isotherm of the dye-activated carbon system. The rates of adsorption were found to conform to the pseudo-second-order kinetics with good correlation. The optimum conditions for preparing activated carbon from Areca Catechu husk for adsorption of methylene blue were found as follow: CO2 activation temperature 800°C, KOH:char impregnation ratio of 3 and a 1211.65 m2/g Brunauer-Emmet-Teller (BET) specific surface area.