Chemically activated carbon using peat soil for heavy metals adsorption in industrial wastewater

The present work is aimed to produce peat soil activated carbon (PSAC) for the removal of heavy metal ions in industrials wastewater. Activated carbon from peat has successfully produced by chemical activation process using sulphuric acid as activating agents. The effect of heating temperature on the carbon content, the physical and chemical characterizations of peat activated carbons were studied. From this study, peat soil heated at 400℃ possess the highest carbon content with concentration of 95.44 % due to the complete degradation of organic matter. The thermogravimetric analysis (TGA) and its derivative thermogravimetric (DTG) confirm the finding where at temperature ≈400°C, peat undergo complete degradation of matter. The heating temperature was set to constant at 400°C for activation process. The BET specific surface area of the activated carbon obtained was 1298.84 m2 g-1. The Raman spectrum gave to main peaks at 1368 and 1590 cm-1 which is attributed to diamond, D and graphitic, G band, respectively. FTIR spectrum analysis showed the carboxyl, ketone, aldehyde, methylene and hydroxyl groups are present on the surface of PSAC due to the activation process with H2SO4. Point of zero charge (pHpzc) of activated carbon is 5.60 which available for heavy metal adsorption due to the adsorbent surface charge was negative. The heavy metal adsorption capacity is evaluate by using an adsorption test. The heavy metal elemental compositions (Cu, Zn, Al, Cr, Pb and Fe) in the industrial wastewater were analysed using ICP – MS. The adsorption test was conducted using batch experiment method where various dosage of PSAC (0.0, 0.2, 0.4, 0.6, 0.8, 1.0 g) mixed to 25 ml water samples. From the adsorption test, the PSAC can be used as adsorbent for industrial waste water treatment

The optimization of heating temperature for carbon extraction from peat soil

This study aims to find the optimised heating temperature for carbon extraction from peat soil. Ccarbon from peat soil was extracted by the pyrolisation process at temperature, T = 200, 300, 400, 500, 600 and 700°C for 5 hours. The carbon, C and silica, Si content extracted from peat soil at various heating temperatures were measured by using an Energy Dispersive X-Ray analyzer (EDX) at 3 points on the sample surface. High atomic percentage of carbon (95.44 %) was measured at T = 400°C, while the highest atomic percentage of silicon was recorded at T = 700°C (30.79 %). The surface morphology of peat soil was analysed using Scanning Electron Microscope (SEM) at 800 magnifying power, and it was clearly seen that peat fragments were pyrolised at high heating temperature with pores enhancement. The molecular structure parameter of the extracted carbon were identified using Laser Raman analysis. The peak positions of D-band and G-band for raw peat soil were observed at Raman shift of 1379.62 and 1549.02 cm-1, respectively. Meanwhile, the D-band for peat soil heated at temperature of 400°C was 1391.56 cm-1 whereas the G-band has peak position at 1562.16 cm-1 . From the Raman spectra of the optimum heating temperature at 400°C, it was revealed that the carbon molecular structure from the peat soil is mainly attributed by graphite and diamond structure