Jurnal Pendidikan Kimia
Not a member yet
236 research outputs found
Sort by
Analysis of Chloride Levels in Well and PDAM Water in Ngelom Village, Sidoarjo
Get PDFChloride is an anion that dissolves easily in water samples and it is the main inorganic anion founded in water samples. Excess of chloride ions in drinking water can damage the kidneys. The aims of this study is to determine chloride levels in well and PDAM water samples in Ngelom Village. Determination of chloride levels in water samples using the Mohr argentometric titration method. The samples used was well water and PDAM water, each was taken from 20 locations in Ngelom Village. The samples were mixed with K2CrO4 indicator and then were titrated using the silver nitrate standard solution until the end point of the titration was marked with a brick red color. The results of the analysis of chloride levels in well water of 92 to 491 mg/L and in PDAM of 57 to 230 mg/L. Based on these results, it can be concluded that chloride levels in both well water and PDAM water samples were below maximum threshold which appointed in Permenkes RI No. 416/Menkes/Per/IX/1990 (≤600 mg/L)
Decoction as an Alternative to Producing Indigo Tarum Areuy (Marsdenia tinctoria) Dyes and Its Role on Fiber Coloration from Cellulose
Get PDFIndigo natural dyes are generally made by maceration-fermentation for 24 - 72 hours impacting on productivity. A faster extraction method is needed by decoction methods. The faster production of indigo tarum areuy dyes is done by decoction at temperatures of 60ºC, 70ºC and 80ºC for 5 minutes, 10 minutes and 15 minutes. The extract was adjusted to reach pH 11. Aeration was carried out 30 minutes and then deposited for 24 hours. Indigo dyes are determined yield, purity of indigo, and evaluation of the quality of the staining results using spectrophotometric methods and color fastness testing of washing. Increased yield of indigo dyes occurs at temperatures of 60ºC and 70ºC. At 80ºC, the yield decreases with increasing decoction time. The best temperature and decoction time for pure indigo yield and the quality of the dyeing results in cotton were at 70ºC for 15 minutes with a yield of 3.625 grams per 500 grams of leaves. The dyeing color of the cotton fabric has increased along with the increase in yield and the purity of the dye. The highest color determination is achieved by a cloth dyed by indigo dyes from the decoction process at 70ºC for 15 minutes, with a K / S value of 3.8754. The extraction time and temperature did not affect the washing fastness
Au Extraction from Mineral Rocks with Aeration-Cyanidation Hydrometallurgy and Comparative Study of Its Effectiveness in Various Methods and Solvents
Get PDFIndonesia is a country with abundant mining potential, one of it is gold (Au) which has a high economic value. Separation of gold metal from mineral rock consists of several methods, such as extraction, hydrometallurgy, and membrane emulsifier technology. These three methods produce different effectiveness of percentage recovery (%recovery), depend on the optimum conditions of each method and type of solvent. This study aims to separate the gold metal from mineral rocks through the hydrometallurgical method with an aeration-cyanidation solvent combination. Hidrometallurgy method is liquid extraction from ores. The test used is a qualitative test of SnCl2 solution and characterization test with XRF. The results showed that the percentage of recovery (%recovery) of Au with aeration and cyanidation process for 24 hours was 92.8%. Aeration and cyanidation better than emulsifier membrane method and hydrometallurgy with sodium bisulphite, hydrogen peroxide, Cyanex 272 and NH4Cl 0.9 M
Pollutant Concentration and Trajectory Patterns of PM2.5 including Meteo Factors in Jakarta City
Get PDFPM2.5 particulate monitoring has been carried out in South Jakarta. The research objective is to examine the effect of meteorology and pollutant trajectories on PM2.5 conditions based on daily and seasonal patterns from January 2016 to December 2017. The sources of PM2.5 data come from DKI Jakarta BPLHD. The data analysis method uses excel to obtain daily and seasonal PM2.5 patterns (rainy season, transition season and dry season). PM2.5 pollutant trajectory patterns were obtained using a single-Particle Lagrangian Integrated (HYSPLIT) forward trajectory derived from NOAA (National Oceanic and Atmospheric Administration). Then the correlation between PM2.5 with meteorological parameters during 2016-2017 was analyzed. The results showed the maximum concentration of PM2.5 in 2016 occurred in the dry season (June-August) of 57.43 µg/m3 and decreased for 2017 by 50.84 µg/m3. Meanwhile, minimum PM2.5 concentration occurs during the rainy season (December-February) which is equal to 20 µg/m3 in 2016, in 2017 PM2.5 decreases to 15.5 µg/m3. The results of running model (HYSPLIT) forward trajectory of PM2.5 pollutants show when dry season pollutant leads to the western part of Jakarta city while the PM2.5 pollutant in rainy season moved from Jakarta city leads to the eastern region
Effect of Heating on the Pretreatment Process for Recycling Li-Ion Battery Cathode
Get PDFThe use of Li-ion batteries has increased with the increasing of portable electronic media. Li-ion batteries have a life cycle hence a recycling process is needed in order to reduce the potential hazard of waste while increasing the economic value of unused battery material, especially its cathode active material. This study used Lithium Nickel Cobalt Oxide (NCA) cathode scrap to be regenerated which NCA material has high energy density and high capacity. The pretreatment process is one of the determinants in the subsequent recycling process. In this study, the effect of heating on the pretreatment process was carried out with variation temperatures of 500-8000C to obtain powder which will be recycled. The combination process of the leaching and co-precipitation was used to regenerate the cathode active material. Atomic Absorption Spectrophotometry (AAS) was performed to determine leaching efficiency using 4M H2SO4 at 400C for 3 hours. X-ray Diffraction (XRD) analysis showed that NCA material has been successfully regenerated which the diffraction peaks of NCA material was in accordance with JCPDS standards. The morphology of NCA material was tested using Scanning Electron Microscopy (SEM). Electrochemical testing uses a cylindrical battery at 2.7-4.2 Volt which the initial specific discharge capacity of the power is 62.13 mAh / g
Synthesis of Nano Silver using Bioreductor of Tristaniopsis merguensis Leaf Extracts and Its Antibacterial Activity Test
Get PDFSynthesis nanosilver from pelawan leaf extract (Tristaniopsis merguensis) has been carried out. The variables of this study were variations in the concentration of AgNO3 1 mM, 1.5 mM and 2 mM. Pelawan leaf extract acted as a bioreductor that converts Ag+ to Ag0. The synthesis was carried out in a ratio of 1: 4 (opposition leaf extract: AgNO3 solution) at 70 °C for 1.5 hours. The results of the UV-Vis analysis showed the maximum at the 1 mM; 1.5 mM; 2 mM AgNO3 concentration were 391 nm, 392 nm and 400 nm, respectively. XRD analysis explained that the resulting nanosilver was crystalline and according the Scherrer equation an average particle size was of 22.8 nm. The antibacterial activity test of nanosilver was carried out by disc method, nanosilver showed the existence of strong antibacterial activity against E. coli and S. aureus bacteria.
Optimization of Thyroglobulin Coated Tube for Thyroglobulin IRMA Kit
Get PDFImmunoradiometric assay (IRMA) is a method of analysis based on immunological reactions of antigens-antibodies binding. This highly specific and sensitive method was used for in vitro diagnosis in small quantity of sample. Center for Radioisotope and Radiopharmaceutical Technology, BATAN has developed Thyroglobulin IRMA Kit using coated tube method that can determine thyroglobulin levels in microgram quantities. Coated tube was made with immobilisation of anti thyroglobulin into polistyrene tube. Development of IRMA kit performed through several steps including: optimization component of kit, optimization assay and kit validation. Optimization of coated tube involved selection and volume of solvent, using blocking and non-blocking agent, and volume of blocking agent. The optimum condition for coated tubes was found to be using 0.1M phosphate buffer pH 7.4 with coating volume of 500 μL, 3% BSA in 500 μL blocking agent 0.1M phosphate buffer pH 7.4, with maximum binding and non-specific binding (NSB) of 60.58 and 1.40%, respectively. The optimized coated tube was found to be stable up to 4 weeks