Jurnal Riset Kimia
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Potensi Daun Sirsak (Annona Muricata L.) sebagai Kandidat Fungisida Nabati Penghambat Pertumbuhan Cendawan Patogen Colletotrichum Gloeosporioides
Get PDFThe attack of the Colletotrichum gloeosporioides fungus causes losses to farmers. The prolonged use of synthetic fungicides to treat this fungus harms the environment and consumers. Soursop leaves (Annona muricata L.) contain antioxidant compounds that act as antifeedants, contact poisons, and stomach poisons for plant pests and can potentially become a vegetable fungicide as a growth inhibitor for Colletotrichum gloeosporioides in postharvest horticulture. This study used a multilevel extraction method with solvents of n-hexane, ethyl acetate, and 95% ethanol. Tests for the content of secondary metabolites of soursop leaf extract in the form of alkaloids, flavonoids, saponins, and tannins were carried out qualitatively and quantitatively using a UV-Vis Shimadzu 1800 spectrophotometer. The inhibition test of the extract against the fungus Colletotrichum gloeosporioides was carried out using disc paper soaked with soursop leaf extract for a certain time. The qualitative test results of soursop leaf extract showed that it contained alkaloids, flavonoids, saponins, and tannins. The fungal inhibition zone test showed the most optimal results on soursop leaf extract with a long extraction time of 144 hours and a content of 50%, indicated by the largest diameter of the inhibition zone against the fungus Colletotrichum gloeosporioides, namely 1.7 cm
Decreasing of Mangan (II) in The Water Using Membrane of Moringa Seed Powder-TiO2 with Variation of Mass TiO2
Get PDFMn (II) is a metal ion commonly used in steel alloys, pigment industries, welding, fertilizers, pesticides, ceramics, and electronics. According to the Regulation of the Minister of Health No. 32 of 2017, the permissible content of Manganese in dug well water is 0.5 mg/L. The purpose of this study was to determine the concentration of Mn (II) ions in water before and after passing through a Moringa Seeds Powder (MSP)-TiO2 membrane 20:1; 20:3; 20:5; 20:7; 20:9 and measure the percentage decrease in the concentration of Mn (II) ions in water after through the MSP-TiO2 membrane. The object of this research is a 55 ppm Mn (II) ion artificial sample at a flow rate of 0.56 mL/minute for 90 minutes with 90-watt radiation UV. The concentration of Mn (II) ion was measured by visible spectrophotometric method, the morphology of MSP, TiO2, and MSP-TiO2 membranes was characterized by SEM-EDX, and its diffraction spectra by X-Ray diffraction. The results obtained that the initial Mn(II) was 55.06 ± 0.031 ppm, the concentration of Mn (II) ions with the MSP-TiO2 membrane of mass MSP-TiO2 were 20:1; 20:3; 20:5; 20:7; 20:9 respectively 36.47±0.00; 44.16±1.15; 44.31±1.04; 44.94±0.94; 42.27±2.61 ppm. The percentage of decrease concentration of Mn (II) ion are 34.19±0.44%; 21.37±0.43%; 20.94±0.85%; 19.24±0.86%; and 19.66±0.86%. The highest percentage decrease in Mn (II) ion concentration was 34.15±0.44% in the variation of mass MSP-TiO2 20:1. This study concludes that the MSP-TiO2 membrane has the potential to reduce the concentration of Mn (II) ions in water
Synthesis of Mg-doped TiO2 Using a Hydrothermal Method as Photoanode on Bixin-Sensitized Solar Cell
Get PDFTitanium dioxide (TiO2) with magnesium (Mg) doping for dye-sensitized solar cell (DSSC) photoanode application has been synthesized. DSSC components used in this study were photosensitizer (bixin), electrolyte (), cathode (platinum), and photoanode (Mg-TiO2). This research aims to determine the characteristics of Mg-doped TiO2 photoanode with variations in dopant concentration based on the results of XRD and DR/UV-Vis analysis, as well as to determine the maximum efficiency conversion energy of DSSC using Mg-doped TiO2 and undoped TiO2 as photoanodes. The synthesis of TiO2 and Mg-TiO2 was carried out using the hydrothermal method with variations in the concentration of Mg dopant of 0, 0.5, 1, and 2% based on the molar ratio. The presenceof 2% of Mg in anatase TiO2 paste decreased the TiO2 band gap from 3.15 to 2.60 eV. Analysis results show that adding Mg dopant decreased the crystal size. Mg dopants on TiO2 could also form new energy levels, which reduced the band gap energy of TiO2. In addition, the increased concentration of Mg dopants also shifted the absorption capacity of TiO2 from the ultra-violet (UV) wavelengths region to the visible light area. The maximum energy conversion efficiency of the DSSCs with Mg-doped TiO2 photoanode of 0.5, 1, and 2% are 0.045; 0.070, and 0.172%, respectively, where these three efficiency values are higher than undoped TiO2 (0.017%). The results proved that the presence of Mg dopants on the TiO2 photoanode can increase the efficiency of DSSC
The Extracted Pectin from Ambarella Fruit Peel (Spondias dulcis) as Biosorbent in Adsorption of Cu(II) Metal Ions
Get PDFHeavy metals are known to seriously injure land plants and animals, including humans, as well as marine species when present in contaminated water. For the batch adsorption technique used in this study, Cu(II) ions were removed from an aqueous solution using an inexpensive environmentally friendly adsorbent prepared from the extracted pectin of ambarella fruit peel. The functional groups of the extracted pectin were studied using Fourier Transform Infrared Spectroscopy (FT-IR). Operational conditions like pH, contact time, and initial adsorbate concentration were investigated. FTIR characterization showed that pectin was successfully extracted from ambarella fruit peel with the appearance of the peaks at 3331.36 cm-1, 2924.02 cm-1, 1727.38 cm-1, 1626.20 cm-1, 1329.31cm−1, 1232.43cm−1, 994.18 cm−1 and these peaks have similar characteristic with a commercial pectin. The maximum uptake of Cu(II) ions was obtained at a pH of 4, a contact time of 90 min, an initial metal concentration of 150 ppm. The extracted pectin has an adsorption capacity of 6.5860 mg/g for the removal of Cu(II) ions from aqueous solution under the optimum adsorption conditions. In addition, the data obtained from contacting the extracted pectin of ambarella fruit peel in Batang Arau River water showed an adsorption capacity of 0.0376 mg/g. Therefore, the pectin that was extracted from the peel of the ambarella fruit could be used to filter out Cu(II) ions from aqueous solutions
Pemanfaatan Zeolit Alam Ende Sebagai Katalis dalam Pirolisis Polietilena dari Sampah Plastik
Get PDFPyrolysis is one way to minimise plastic waste. This process requires a catalyst such as zeolite. Natural zeolite needs to be activated to increase its catalytic activity. Therefore, this research was carried out by activating Ende's natural zeolite using 1% hydrofluoric acid (HF), 6M hydrochloric acid (HCl), and 1M ammonium chloride (NH4Cl) to be used as catalysts in the pyrolysis of polyethylene from plastic waste. Pyrolysis was carried out at operating temperatures of 300 oC, 350 oC, 400 oC, and 450 oC, and treated with a catalyst composition of 0%, 5%, 10%, and 15% from 1000 grams of polyethylene. Based on the results of the study, it was concluded that activation of Ende's natural zeolite could change the chemical and physical properties of Ende's natural zeolite, including crystallinity, surface area, pore volume, and pore radius, and acidity to serve as a catalyst. Treatment of 10% catalyst from 1000 mg of plastic at an operating temperature of 400oC reduced the activation energy to 4.371.1 cal/mol and produced 80% more paraffin fraction in polyethylene pyrolysis oil from plastic waste
Synthesis and Characterization of Adsorbent Materials Magnetite Mercaptosilicate Ion Imprinted Polymer as Cadmium Ion Adsorbent
Get PDFCadmium (Cd) is a toxic heavy metal with the active property of reacting with other components so that cadmium residues can quickly enter the food chain and cause cardiovascular, kidney, and cancer diseases. The purpose was to synthesize the magnetite mercaptosilicate ion imprinted polymer adsorbent material by forming Ion-Imprinted Polymer as a template, to analyze the characterization results using XRD and SEM-EDS, and to determine the adsorption test results for Cd metal ions. The results of the characterization of XRD show that there is a broad peak at a diffraction angle of 2θ= 20-220 with an amorphous structure, which is silica, and there is a high peak at a diffraction angle of 2θ= 35.55140 which indicates magnetite. The results of SEM analysis with magnifications of 500x, 1000x, and 5000x showed that the surface morphology of the particles was not uniform. For the EDS results, it can be seen that the components of the magnetite mercaptosilicate ion imprinted polymer material are elements C, O, Si, S, and Fe, with a mass percentage of 25.0%; 41.2%; 29.9%; 3.28% and 0.8%. The results of the adsorption test for the Magnetite-IIP-Mercaptosilika Material were able to adsorb Cd ions with the highest adsorption capacity of 10.536 mg/g at a concentration of 100 mg/L. Then the selectivity coefficient value of the Ion Cd metal ion is 2.32 greater than 1, indicating that the selectivity of the magnetite mercaptosilicate ion imprinted polymer material is much higher for Ion Cd metal ions than for Cu and Cr ions with a selectivity coefficient of 0.1 and 0.26
Sintesis dan Uji Fotostabilitas Kompleks Zn(II)-Astaxanthin
Get PDFAstaxanthin is a pigment from the carotenoid group found in algae, shrimp, and crabs. Due to its chemical structure, astaxanthin has many health benefits but low stability against direct exposure to light and oxygen. In this study, the Zn-astaxanthin complex was synthesized using a reflux reactor at 37o and 60oC. Complex compounds were analyzed using a UV-Vis spectrophotometer and FTIR. The UV-Vis spectrophotometer analysis showed a bathochromic shift in acetone (475 to 477 nm). In comparison, in dimethyl sulfoxide, a hypsochromic shift (493 to 475 nm) was observed, and a new absorption peak was observed at 330 nm. FTIR analysis shows a decrease in the intensity of the C=O stretching vibration and -OH group vibration at 1712 and 1219 cm-1, respectively. This indicated an interaction between the metal ion Zn2+ and astaxanthin. Zn-astaxanthin has better stability than astaxanthin during irradiation, using a halogen lamp at a light intensity of 300 W/m2 for 6 hours. Based on the zero-order degradation kinetics model, the degradation rate constant of the Zn-astaxanthin complex was 0.0621, smaller than that of astaxanthin (0.0880)
Optimasi Proses Hidrolisis Rumput Laut Ulva Reticulata dengan Pelarut HNO3 untuk Produksi Bioetanol
Get PDFOne alternative to make biofuels and replace petroleum-based fuels is to convert non-food ingredients from Ulva reticulata seaweed into bioethanol. Seventy percent of the earth's surface is covered by microalgae and seaweeds that can be converted into bioethanol. Ulva seaweed contains 50.3% carbohydrates in the form of heteropolysaccharides such as glucose, arabinose, rhamnose and xylose. Optimization of the seaweed hydrolysis catalyzed by HNO3 using Microwave irradiation was done by varying acid concentration (1, 3, 5, 7%), hydrolysis time (30, 40, 50, and 60 minutes), and hydrolysis temperature (75, 100, 125, 150°C). Fermentation was carried out by varying inoculum concentrations (6, 8, and 10% (v/v)) for 5, 6 and 7 days at a temperature of 30°C and a pH of 4.5. Analysis of the surface texture of the sample was carried out by Scanning Electron Microscopy (SEM). The analysis of reducing sugars concentration was carried out using the dinitrosalicylate (DNS) method. Ethanol analysis was carried out by Gas Chromatography (GC). The results of SEM analysis showed that prior to hydrolysis, the surface morphology of the powder was still compact and intact. Whereas after being hydrolyzed with HNO3 it was seen that the surface texture of the powder suffered significant damage. The hydrolysis results showed that the optimum conditions during the pretreatment of U. reticulata powder was at acid concentration of 7%, reaction time of 50 minutes, reaction temperature of 150°C and 250 watts of power which gave hydrolysate with reducing sugar concentration of 86.5 g/L. Fermentation of the hydrolysate using yeast Saccharomyces cerevisiae produced bioethanol with concentration of 37.2% as analyzed using a gas chromatograph
Karakterisasi Selulosa dan Selulosa Asetat dari Limbah Cangkang Biji Pala (Myristica Fragransi) Aceh Selatan
Get PDFNutmeg seed shell waste contains 21.34% cellulose, 12.93% lignin, 53.67% crude fiber, 6.16% ash, 0.11% phenol, and 0.38% carbonyl. The content of cellulose and lignin in the nutmeg shell waste is quite large, so it can be used as something of value. Cellulose can be synthesized into cellulose acetate. The use of cellulose acetate is very diverse, such as in the film industry, biodegradable plastics, paper coatings, metals, and glass, as an adhesive for topographic films as the main raw material in membrane synthesis processes. Therefore, it is necessary to characterize cellulose and cellulose acetate from nutmeg shell waste (Myristica fragrance) in South Aceh. The method used is in the form of cellulose isolation using the soxhletation process, then bleaching and hydrolysis processes are carried out, then it is synthesized into cellulose acetate. Characterization of cellulose by determining % yield, cellulose content, ash content, moisture content, FTIR, XRD. Characterization of cellulose acetate by determining the acetyl content and FTIR. The characterization results obtained ash content of 3.04%, moisture content of 15.55%, yield of 35.36% and 5.29% cellulose content. XRD characterization obtained a diffractogram peak at an angle of 2θ = 22.2111o, a crystallinity of 96% and a crystal size of 0.5292 nm. Characterization of the functional groups of cellulose in the form of stretching O-H, C-H and C-O groups which are at wave numbers 3331.04 cm-1, 2871.29 cm-1 and 1024.96 cm-1. Functional groups of cellulose acetate in the form of O-H, C=O, acetyl C-O, bent C-H and C-O groups are at wave numbers 3348.82 cm-1, 1719.61 cm-1, 1227.23 cm-1, 1369.50 cm-1 and 1028.62. The acetyl content is 39.18% and the degree of substitution is 2.65%