Pembuatan dan Karakterisasi Elektroda Karbon Aktif dengan Karbonisasi dan Aktivasi Bertingkat Menggunakan Gas Co2 dan Uap Air

Has been conducted a research to produce cell supercapacitor electrodes of activated carbon (AC) which were prepared using rubber wood sawdust (SGKK). KA electrode is made via carbonization and activation method integrated using CO2 and water vapor for 4 hours. N2 flow is maintained from room temperature to a temperature of 600 0C, followed by CO2 to a temperature of 900 0C for 2 hours, water vapor flow continued for 2 hours at a temperature of 900 0C. Crystallite structure is reviewed samples using X-Ray Diffraction (XRD). Methods Scanning Electron Microscopy (SEM) was used to analyze the surface morphology. While the composition of the content chemical elements the samples were analyzed using Energy Dispersive X-ray (EDX). Electrochemical properties of samples were tested using the method Cyclic Voltammetry (CV). Overall characterization of physical properties indicates that the sample is a carbon material with a carbon content of 90%. Electrochemical test proved that the integrated activation method can produce a electrode with excellent performance with a specific capacitance value of 72 F/g

Pembuatan dan Karakterisasi Karbon Aktif Monolit dari Kayu Karet dengan Variasi Konsentrasi Koh untuk Aplikasi Superkapasitor

Development of monolithic carbon electrodes with a combination of physical and chemical activation process can improve performance of cell supercapacitor. Monolithic carbon electrodes were made from rubber wood cross-section of the printed form of pellets, then were carbonized at temperature of 600ºC in N2 gas atmosphere and followed by physical activation process at 900ºC for 2 hours in a CO2 gas atmosphere. KOH of 1 and 5 M and HNO3 of 25% solutions were used as of the chemical activation in order to activate functional groups. Characterization of electrochemical supercapacitor cell utilized two-electrode of cyclic voltammetry with 1 M H2SO4 solution was used as electrolyte. Scanning electron microscope and X-ray diffraction were carried out to study the structure of surface morphology and crystalline properties of monolithic carbon electrodes. Specific capacitance for electrodes 1 M KOH and 5 M KOH was obtained as high as 71.08 and 115.38 F/g respectively. These results indicate that increasing the concentration of KOH can improve the performance of the electrode supercapacitor cells

Penentuan Kualitas Batu Bata Merah Berdasarkan Konduktivitas Termal

A compressive strength testing ( ) and thermal conductivity testing (k) havebeen performed on red bricks from the district of Tenayan Raya and Rumbai. Thisresearch using a compression machine, iron, solder, thermometer, styrofoam and itspurpose was to prove the theory of the thermal conductivity having relationship tocompressive strength. The result showed that the highest compressive strength due tothe conventional red brick of Rumbai district is 10.82 x 10 5 N/m 2 and the lowestcompressive strength due to the press red brick of Tenayan Raya district is 3.67 x 10 5N/m 2 . The research results of thermal conductivity showed that the thermal conductivityvalue of the best sample of conventional red brick of Rumbai district is 1.05 J/sm C andthe thermal conductivity value of the lowest sample of press red brick of Tenayan Rayadistrict is 0.857 J/sm C . The affecting factor of the quality of red bricks is density. Thedensity of conventional red bricks of Rumbai district for compressive strength andthermal conductivity, are 2486.880 Kg/m 3 and 2200 Kg/m 3 , respectively. Meanwhileaverage density of press red brick of Tenayan Raya district for compressive strength andthermal conductivity are 1696 Kg/m 3 and 2000.5 Kg/m 3 , respectively. Based on theresult there was in relationship between compressive strength and thermal conductivitywhich was discribed by the regression equation Y 2 x 10 7 X 0 . 81

Efek Variasi Waktu Ball Milling terhadap Karakteristik Elektrokimia Sel Superkapasitor Berbasis Karbon

Supercapacitor electrodes from rubber wood saw dust (RWSD) have been fabricated using experiment method to study the ball milling variation time on performance of the supercapacitor cells. The carbon electrodes were prepared with time variation of 20, 40, and 80 hours and thickness of 0.2 mm. Carbon electrodes were carbonized at 600oC and followed by physical activation method in CO2 gas atmosphere on the constant temperature of 900o C, and chemical activation was performed by KOH as an activating agent. Densities of the electrodes were 0.849 g/cm3 , 0.892 g/cm3 , 0.982 g/cm3 respectively. XRD measurement showed the peaks of carbon electrodes at 2θ of 24.091o and 44.473o which represented the presence of carbon materials with their crystal orientation of (002) and (100). SEM micrograph on magnification of 1000X showed that the pore distribution of the carbon electrodes dominant on macropores. This study found that the effects of increasing of ball milling time influenced the electrochemical properties of supercapacitor electrodes fro m RWSD. The optimum supercapacitor performance was found on 20 hour milling time electrode and had a specific capacitance of 55.414 F/g