This paper concerns on regeneration of spent bleaching earth (SBE) as a filler in biodegradable nanocomposite. The nanocomposite were produced from two different production methods, solvent casting and extrusion. SBE can be used as filler after being regenerated by removing oil and impurities. A regeneration method for SBE was conducted using chemical treatment. Regeneration process was proved to be succesful as shown in FTIR with the absence of peak at 2850 cm—1 – 2930 cm−1 and 1730 cm−1 indicating the disappearance of free fatty acids and ester bonds from regenerated bleaching earth (RBE). The RBE was then applied as filler for PLA-Nanocomposite, biodegradable plastic, a suitable substitute for conventional plastic. The production of nanocomposite used two different surfactants, namely octadecyl amine (ODA) and trimethyl stearyl ammonium chloride (TSC) at two different concentration (20 mmol and 40 mmol). The mechanical property of PLA-Bentonite nanocomposite was then analyzed for tensile strength and permeability. The highest tensile strength and lowest gas permeability was obtained by nanocomposite that used 40 mmol TSC as surfactant, with 12.48 MPa and 0.017 g/day, respectively. Moreover, addition of regenerated bleaching earth to PLA-Nanocomposite during production using extrusion and solvent casting had slight different effect. XRD pattern of all extruded PLA-nanocomposite samples indicated the formation of exfoliated structure, as shown in XRD pattern with very low intensity peak around 2 nm at 2? = 5, while only a few of samples of PLA-nanocomposite created by solvent casting indicating the same structure.

With the increasing development of the battery and electric vehicle industry, student's and teacher's understanding of lithium batteries and skills in assembling electric bikes are very important in competing for jobs in these fields. Educational activities regarding batteries and training on assembling electric bike are carried out at SMK Muhammadiyah 6 Karanganyar, because there were no facilities that support the learning and teaching process about electric vehicles and batteries. The method used in this training is lecture, discussion and practice method. The material presented was about the technology of making lithium batteries and electric bike components. While practical activities include the stages of converting conventional bikes into electric bikes with energy from lithium batteries. This activity shows that participants can understand batteries and can apply batteries to electric vehicles, especially electric bikes.

Spent nickel catalyst is the catalyst residue that has lost its catalytic function. Spent nickel catalyst contains Ni metal which is already high and environmentally hazardous. This problem can be solved by recovering the spent nickel catalyst as an anode and combined with lithium nickel cobalt oxide (NCA) as a cathode for lithium ion batteries. A study about it has never been conducted. The method used to treat the spent catalyst was acid leaching using 1 M citric acid and 4 M hydrochloric acid at 70-80°C for 2 hours, then continued with precipitation and thermal decomposition. Another method employed was direct sintering at 800°C for 12 hours. Material characterisation was carried out by X-Ray Diffraction (XRD), Atomic Absorption Spectrophotometry (AAS), Fourier Transform Infra-Red (FTIR), and X-Ray Fluorescence (XRF), while electrochemical performance was carried out by NEWARE Battery Analyzer and BTS software. The results of this study indicate that Ni can be recovered with hydrochloric acid as much as 15.387 gr higher than citric acid as much as 11.831 gr from 20 gr sample. The XRD pattern also indicates the presence of crystals NiO I and NiO II in the leached and sintered material. The results of acid leaching in the form of NiO I was perfectly formed, but NiO still has a little impurity. Electrochemical performance was tested with a cylindrical battery resulting in a discharge capacity of 37.210 mAh g−1.

Zeolite A has been successfully synthesized from coal fly ash by using fusion followed by hydrothermal method. This paper describes the characterization of zeolite A. The effects of hydrothermal time, Si/Al molar ratio, and alkalinity in the converting coal fly ash to zeolite A were also investigated. The coal fly ash was obtained from a local power plant at East Java, Indonesia and contained major oxides such as SiO2 (18.60 wt%), Al2O3 (7.18 wt%), Fe2O3 (40.20 wt%), CaO (25.20 wt%). The fusion hydrothermal method consists of the following steps: pre-treatment, fusion of coal fly ash with sodium hydroxide, aging, and hydrothermal process. The synthesized material was characterized by using X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR), and specific surface area analytical method. The results show that the products contain zeolite A as the major phase, while the highest specific surface area of zeolite A is 37.121 m2/g. It implies that zeolite A as a higher value added product can be obtained from a solid waste/by-product of power plant, which has wide range applications, including for ion exchange and heavy metal adsorbent from waste water.

Nanocomposites were prepared by melt extrusion technique using single screw extruder and subsequent hot compression. In this work, poly lactic acid-clay nanocomposites were obtained using two types of clays, namely commercial montmorillonite (Cloisite 30B) and commercial bentonite. Nanocomposites were prepared at low clay composition of 0.5, 1, 3, and 5 wt.% of clays. From XRD spectra, the partially exfoliation of nanoclay layers were occurred during melting extrusion. It resulted in improvement of mechanical properties, such as Young’s modulus, tensile strength, and elongation at break. The highest tensile strength was obtained by the addition of 0.5 wt.% commercial bentonite increasing about 23.25% compared to the neat PLA. The increasing composition of clays revealed a decrease in mechanical properties due to filler-filler interaction. Furthermore, water absorption of nanocomposites up to `1 wt.% of clays better than the neat PLA. Biodegradability was enhanced in the presence of higher clay composition due to high hydrophilicity of clay, high water uptake, and high interactions. The results show that the weight loss of the neat PLA and the nanocomposite with the addition of 5 wt.% of Cloisite 30B are 4.0% and 10.8%, respectively.