Chairul Irawan

Facile Strategy for Surface Functionalization of Corn Cob to Biocarbon and Its Catalytic Performance on Banana Peel Starch Hydrolysis

The sulphonated biocarbon (C-SO 3 H) has been prepared from carbonization of corn cob and followed by one-step hydrothermal treatment. This research focus on characterization of C-SO 3 H and evaluate the capability of C-SO 3 H for hydrolyzed banana peel starch, and also investigate the optimum concentrations of substrate and the reaction time for hydrolysis. The C-SO 3 H was produced from corn cob (±60 mm mesh); it was carbonized at 400 °C for 1 hour. The resulting carbon was sulphonated by hydroxy ethyl sulphonic acid at 180 °C for 4 hours, and then washed with 50% methanol and water, and then resulting biocarbon was dried at 80 °C for 6 hour in oven. Based on Scanning Electron Microscopy (SEM) observation, structure morphology of corn cob was changed due to carbonization process. The C-SO 3 H after sulphonation has random pores with diameter around 3 µm–10 µm. The X-Ray Diffraction (XRD) showed increased of crystalline index of corn cob about 133% after carbonization. Analysis of EDX result for S component on C-SO 3 H is 3.79% w/w and capacity of H + is 1.447 mmol/g. The apparent peaks of -SO 3 H functional groups (1207 cm -1 and 1720 cm -1 ) on C-SO 3 H were indicated the by Fourier Transform Infra Red (FTIR). Optimum hydrolysis concentration of banana peel starch is 7% w/v for 60 min at 100 o C which Total Reducing Sugar (TRS) concentration about 0.688 mg/mL. Reusability of C-SO 3 H for 4 repeated used which showed a good performance that only 6% of decreasing activity of C-SO 3 H. The utilization of corn cob can be enhanced of corn cob and also it can be utilized as heterogeneous catalyst.

Biocomposite Materials of Eleocharis dulcis Fibers with Iron (III) Nanoparticles and Its Potential for Sasirangan Textile Wastewater Treatment

Eleocharis dulcis (Chinese water chesnut), locally Kalimantan named Purun Tikus, is a plant that grown in highly acidic swamps areas in South Kalimantan. Eleocharis dulcis (ED) , was usually used as material for traditional handicrafts. Therefore it is necessary for develop and innovate to convert the material becomes valuables. This research focus on the study of biocomposite nanoparticles of ED and its potentials as an adsorbent to reduce concentration of Pb 2+ ion, Total Suspended Solid (TSS) and color from Sasirangan textile industry wastewater. The synthesis of the biocomposite nanocomposite was made by solvothermal synthesis. Firstly, ED stemsdried was cutted to small size (250 micron), then through delignification process to eliminate lignin by 1% w/v NaOH solution. ED delignification put into hydrothermal reactor, right afterward was carried out by one-pot solvothermal reaction of 1,6-diaminohexane, iron (III) chloride hexahydrate, and ethylene glycol at 200 o C for 6 h.The process was produced two types of biocomposites, without the amino group (EDB-M) and the amino group (EDB-MH). The characterization results shown by SEM, magnetic nanoparticles have been formed on the surface of EDfiber.The ED biocomposite nanoparticles (EDB) with diameter size around 30–50 nm could be obtained. X-Ray Diffraction (XRD) analysis showed treatment of EDdelignification was increased the porosity of the fiber, shown by increased Crystalinity Index (CrI) about 72.75%. The biocomposites adsorbent, EDB-M and EDB-MH had adsorption capacity for Pb 2+ ions about 44.21 mg/g and 55.62 mg/g at equilibrium pH (pH e ) of 6 and equilibrium time of 2 hour. The effectiveness of reduced TSS was about of 91.9% and 98.1%. Beside that, the colour intensity of color was decreased about 96.7% and 97.8% for the EDB-M and EDB-MH, respectively.