Efluen pewarna yang merbahaya daripada kilang tekstil, kertas, kosmetik dan pemproses makanan telah menjadi kebimbangan utama kerana ia toksik kepada alam sekitar. Kajian ini bertujuan untuk meghasilkan karbon teraktif (KT) daripada tempurung kelapa (TK) untuk menyingkirkan metelina biru (MB) daripada larutan akuas. Karbon teraktif berasaskan tempurung kelapa (KTTK) telah disediakan melalui proses pengaktifan fizikal dengan menggunakan penyinaran gelombang mikro di bawah pengegasan karbon dioksida (CO2). Kesan masa hubungan (0-24 jam), kepekatan awal (25mg/L-300mg/L) dan suhu (30˚C, 45˚C dan 60˚C) terhadap prestasi penjerapan KTTK telai dinilai. Keadaan optimum untuk penyediaan KTTK diperoleh masing masing pada kuasa 440W dan masa 6 minit dengan menggunakan kaedah permukaan respon. KTTK yang dioptimumkan mempunyai luas permukaan BET yang tinggi, luas permukaan liang-meso, jumlah isipadu liang dan karbon tetap masing masing sebanyak 658.44m2/g, 502.31m2/g, 0.4898cm3/g and 82.13%. Liang KTTK adalah sejenis liang-meso dengan diameter liang sebanyak 5.72nm. Model Langmuir dan model pseudo-kedua telah didapati sebagai model terbaik untuk data keseimbangan dan data kinetik. Kapasiti penyerapan lapisan-mono MB keatas KTTK ialah 217.39 mg/g. Sistem penjerapan adalah bersifat endotermik dan ia ditadbir oleh penjerapan fikizal. Kajian mekanisme memdedahkan bahawa proses penjerapan MB keatas KTTK adalah dikawal oleh mekanisme difusi filem.
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The hazardous dye effluent from the textile, paper, cosmetic and food processing plant have become a major concern because of the toxicity to the environment. This study aims to synthesis activated carbon (AC) derived from coconut shell (CS) in order to remove methylene blue (MB) dye from aqueous solution. The coconut shell based activated carbon (CSAC) was prepared via physical activation process by using microwave irradiation under the flow of carbon dioxide (CO2) gasification. The effect of contact time (0-24 hours), initial concentration (25mg/L-300mg/L) and temperature (30˚C, 45˚C and 60˚C) on the adsorption performance of CSAC were evaluated. Optimum condition for the CSAC preparation was obtained at power and time of 440W and 6 minutes, respectively by using response surface methodology (RSM). The optimized CSAC has high BET surface area, mesopore surface area, total pore volume and fixed carbon of 658.44m2/g, 502.31m2/g, 0.4898cm3/g and 82.13%, respectively. The pore for CSAC was the mesoporous type with pore diameter of 5.72nm. Langmuir isotherm and pseudo-second-order was found as the best fitted model for MB adsorption equilibrium and kinetic onto CSAC. The monolayer adsorption capacity of MB onto CSAC was 217.3 mg/g. The adsorption system was endothermic in nature and it was governed by physisorption. The mechanism studies revealed that the adsorption process of MB onto CSAC were controlled by film diffusion mechanism.
Synthesis of microwave-assisted coconut shell based activated carbon for removal of methylene blue dye from aqueous solution / Nazatul Shima Nordinn