KOVALEN: Jurnal Riset Kimia
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Pemanfaatan Lumpur Minyak dengan Solar sebagai Energi Alternatif Bahan Bakar: Utilization of Oil Sludge with Diesel as Fuel Alternative
Get PDFOil sludge resulting from crude oil processing in the petroleum industry could have a negative impact on the environment. Oil sludge could also be classified as hazardous waste and able to damage the environment and human health. Therefore, it was necessary to solve this issues. Oil sludge hydrocarbon utilizing to get higher value was one of solution offered by these research. In the utilization process, filtration method was used at first procedure and followed by diesel mixing at ratio 1:0.1, 1:0.2, 1:0.3, 1:0.4, and 1:0.5. The mixture was then analyzed for several parameters such as heating value, moisture content, ash content, and flashpoint. The results of heating values ranging from 5.966 calories/ gram to 7.210 calories/ gram, the flashpoint was from 38 â°C to 76 â°C, the water content was from 51.89% to 54.52%, the ash content was from 12.3% to 18.03%. The results showed that utilization of oil sludge could be used as liquid fuel alternative energy.
Keywords: oil sludge, energy alternative, liquid fue
Studi dan Aplikasi Elektroda FeTiO3-TiO2/Ti untuk Degradasi Reactive Blue 160 dengan Metode Fotoelektrokatalisis: Study and Application of Photoelectrocatalytic FeTiO3-TiO2/ Ti Electrode to High-Degradation of Reactive Blue 160
Get PDFThe manufacture of titanium dioxide (TiO2) electrodes is made by anodizing method and coated with ilmenite (FeTiO3) through a dip-coating technique. The ilmenite (FeTiO3) coated TiO2/Ti plate electrode was developed for the degradation of the reactive blue 160 dye under photoelectrocatalytic UV and Visible light irradiation. The performance of FeTiO3-TiO2 / Ti composites degrades reactive blue 160 under UV irradiation and is visible photoelectrocatalytically compared to TiO2. The results of XRD characterization of TiO2 crystals in the form of anatase at 2θ, namely 35.1 ° (110), and the substitution of Fe dopant on TiO2 in the form of anatase and rutile crystals. FTIR data indicated the presence of Fe-O bonds at wave numbers <700 nm. SEM-EDX results showed a thin layer of FeTiO3 was formed, indicating that the dip-coating method was effective in the coating process. The performance of the FeTiO3-TiO2 / Ti electrode has the highest activity against the oxidation process under visible light than the TiO2/Ti electrode. The results of degradation of reactive blue 160 dye with a concentration of 0.5 ppm by photoelectrocatalytic showed that the TiO2 / Ti and FeTiO3-TiO2/Ti electrodes were active in visible irradiation with degradation rate constants of 48% and 69%.
Keywords: Electrodes, ilmenite, TiO2 / Ti, degradation, reactive blue 160, photoelectrocatalysi
Adsorbsi Ion Logam Cu (II) Menggunakan Biomassa Daun Genjer (Limnocharis flava): Adsorption of Cu (II) Ions by Biomass of Genjer Leaves (Limnocharis flava)
Get PDFThe adsorption of Cu (II) ions by Genjer (Limnocharis flava) biomass has been carried out. This research aims to determine the optimum pH of the plant and the contact time between the metal ion Cu (II) with the plant that produces the highest absorption, as well as knowing the best adsorbent mass for absorption between Cu (II) metal ions and genjer plants. The study used a completely randomized design (CRD) with variables of pH, contact time, and adsorbent mass. The testing of the absorption of the Genjer leaves biomass against Cu (II) was carried out with Atomic Adsorption Spectrophotometric (AAS). The results showed that the optimum absorption produced was 83.34% at pH 4, and 91.54% with the highest contact time of 30 minutes, and 82.04% with an adsorbent mass of 1 gram.
Keywords: Limnocharis flava, pH, contact time, adsorbent mass, adsorption, Cu (II) io
Penentuan Aktivitas Antioksidan dan Kandungan Flavonoid Total Ekstrak Daun Papasan (Coccinia grandis L.) Berdasarkan Perbedaan Pelarut Polar : Determination of Antioxidant Activity and Total Flavonoid Contents Extract of Papasan Leaves (Coccinia grandis L.) Based on The Differences Polar Solvents
Get PDFPapasan leaves have several properties, including antihyperglycemic, diabetes, antipyretic and antioxidant. Minor metabolite compounds that have the potential as antioxidants from this plant are flavonoids, alkaloids, saponins, and tannins. This study's purpose to determine the antioxidant activity and the flavonoid total contents of Papasan (Coccinia grandis L.) leaf extract based on the differences in polar solvents. The polar solvents used were ethanol, methanol, and water. Extraction used by maceration and dekokta. The antioxidant activity and the flavonoid total contents were established by UV-Vis spectrophotometry according to the decrease in absorbance at a maximum wavelength of 515 nm by the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. Determination of antioxidant activity and the flavonoid total contents were excluded on quercetin comparisons. The values of IC50 and the flavonoid total contents in the ethanol extract respectively were 287.92 ppm and 49.825 mg QE/g while the IC50 values and total flavonoid levels in the extract of methanol were 73.29 ppm and 50.415 mg QE/g. In the extract of the water, the value of IC50 was 39.80 ppm and the total flavonoid contents were 50.415 mg QE/g. The conclusions of these studies were that the most antioxidant activity was found in water extract, while water and methanol extract had the same and highest levels of total flavonoids
Skrining Fitokimia dan Uji Aktivitas Antibakteri Fraksi Etil Asetat dan n-Heksana dari Daun Mangga Kasturi (Mangifera casturi Kosterm.): Antibacterial Activity Test of Ethyl Acetate and n-Hexane Fraction from Kasturi Mango Leaves (Mangifera casturi Kosterm.)
Get PDFKasturi mango (Mangifera casturi Kosterm.) is a typical mango of South Kalimantan. Kasturi mango leaves are reported to have antioxidant activity and are potential for treating various diseases, including diseases related to antibacterial. This study examines the antibacterial activity of ethyl acetate fraction and the n-hexane fraction of mango musk leaves on bacteria that cause acne. Experimental research started with plant determination, making extracts and fractions, phytochemical screening, and antibacterial testing against Staphylococcus aureus and Propionibacterium acnes using the disk diffusion method. The study results found that the ethyl acetate and n-hexane fractions had weak antibacterial activity against S. aureus and P. acnes bacteria, which cause acn
Aktivitas Antischistosomiasis Sediaan Nanopartikel Ekstrak Biji Pinang pada Tikus Putih Jantan Terinfeksi Schistosoma japonicum: The Antischistosomiasis Activity Test on Nanoparticles Ethanolic Extract of Betel Nut to Male Rats Infected with Schistosoma japonicum
Get PDFSchistosomiasis is a disease caused by Schistosoma japonicum worms and Oncomelania hupensis lindoensis as the intermediate snails. Praziquantel is a drug used to reduce the prevalence of schistosomiasis. However, its use has several side effects such as headaches, dizziness, nausea, vomiting as well as abdominal, joint, and muscle pain. The development of alternative drugs is a solution to reduce side effects. Betel (A. catechu) seeds are known to the public to have an anthelmintic effect because they contain alkaloids, tannins, flavan, phenolic compounds, as well as arecoline. To increase the bioavailability and efficacy of the extract, the seeds were prepared in the formulation of nanoparticles. This study aims to determine the antischistosomiasis activity of the ethanol extract nanoparticles of betel nut as an antischistosomiasis. The rats were divided into 9 treatment groups consisting of normal, negative and positive control groups, extract treatment and treatment of nanoparticle preparations with dose variations of 30, 60, and 120 mg/kgBW. The parameter observed was the number of S. japonicum eggs in rat feces before and after treatment. Data obtained from the mean number of S. japonicum eggs was tested for normality with Saphiro-Wilk test, and showed that the data were not normally distributed. Furthermore, nonparametric statistical analysis was carried out with Kruskal-Wallis which showed there was no significant difference in the mean number of S. japonicum eggs in all treatment groups. The results showed that the ethanol extract nanoparticles of A. catechu had antischistosomiasis activity
Kapasitas Bioadsorpsi Bakteri Simbiosis Spons Laut Terhadap Kontaminan Logam Berat: Bio-adsorption Capacity of Marine Sponge Symbiosis Bacteria on Heavy Metal Contaminants
Get PDFHeavy metal pollution in the marine environment is quite high. Arsenic and Mercury are two types of dangerous heavy metals because they are toxic and are often found as components of pollution. The research objective was to determine the bio-absorption capacity and efficiency of sponge symbiotic bacteria against arsenic and mercury contaminants. The bio-absorbent material was used by two bacterial isolates, namely Bacillus licheniformis strain ATCC 9789 (Bl.6), the sponge symbiont Auletta Sp and Acinetobacter calcoaceticus strain PHCDB14 (Ac.8), the sponge symbiont Callyspongia aerizusa. The isolates were prepared through culture, then incubated 2 x 24 hours, suspension Bl.6 and Ac.8 were made, then adapted for 24 hours. Interaction with As3 + and Hg2 + contaminants with a concentration of 100 ppm in vials with time variations 0, 4, 8, 12, 16 days. The resulting interactions are extracted, concentrated, and acidified. The bio-absorption capacity and efficiency were determined based on absorption data using Atomic Absorption Spectrometry (AAS). The average efficiency of the bio-absorption of isolate Bl.6 against As3+ = 99.95%, Hg2+ = 88.49%, while isolate Ac.8 against As3+ = 99.95% and Hg2+ = 85.73%. Based on efficiency data, capacity and bio-absorption power relative to Bl.6 = Ac.8 against As3+ and Bl.6 ≥ Ac.8 contaminants to Hg2+. Isolates Bl.6 and Ac.8 adsorbed more strongly against As3+ contaminants than Hg2+
Analisis Metabolit Sekunder dan Aktivitas Ekstrak Etanol Kulit Buah Salak (Salacca zalacca (Gaertn.) Voss) Terhadap Kadar Glukosa dan Ureum Kreatinin Tikus Putih Jantan (Rattus norvegicus): Analysis of Secondary Metabolites and Activity of Ethanol Extract of Snake Fruit Peel (Salacca zalacca (Gaertn.) Voss) on Glucose and Ureum Creatinine Levels of Male White Rats (Rattus norvegicus)
Get PDFThe snake fruit peel (Salacca zalacca (Gaertn.) Voss) traditionally has several health benefits, one of which is to treat diabetes mellitus. This study aimed to determine the content of secondary metabolites in the ethanolic extract of snake fruit peel and its activity on glucose and urea creatinine levels in male white rats (Rattus norvegicus). Phytochemical screening of extracts was carried out qualitatively and quantitatively using UV-Vis Spectrophotometry. This study is a laboratory experimental study using 30 test animals divided into 6 treatment groups (normal control, negative control, positive control, 70 mg/kg BW, 140 mg/kg BW, and 280 mg/kg BW). The results showed that the ethanol extract of the bark of the salak fruit contained 7.61 %w/w alkaloids, flavonoids 0.041% w/w, tannins 1.18% w/w, and saponins 2% w/w. Ethanol extract of salak fruit peel dose of 140 mg/kg BW affected decreasing blood glucose and urea creatinine levels. The skin of the salak fruit has the potential to be further investigated as an antidiabetic
Kajian Kadar Akrilamida dalam Kopi Arabika dengan Variasi Suhu Penyangraian: Study of Acrylamide Levels in Arabica Coffee with Variations in Roasting Temperature
Get PDFAcrylamide levels in Arabica coffee at various roasting temperatures have been determined. Coffee beans are roasted at 160°C, 180°C, and 210°C for 8 minutes. Analysis was carried out using High-Performance Liquid Chromatography (HPLC) with C-18 reversed-phase, mobile phase using methanol and 0.1% phosphoric acid solution (5:95), flow rate 1 mL/min, UV-Vis detector 198 nm wavelength. Acrylamide levels in Arabica coffee are 160°C of 14.665 ppm, 180°C of 15.973 ppm, and 210°C of 18.501 ppm. Based on the results of the acrylamide content in Arabica coffee, the higher the roasting temperature, the greater the acrylamide content. ANOVA test regarding the normality test sig value of 0.637, 0.463, and 0.637 normally distributed. Based on the homogeneity test, it was found that the variation between groups was the same or homogeneous. The results of the ANOVA test stated that there were differences in the acrylamide levels of Arabica coffee in the roasting temperature difference group and the results of the post hoc Bonferroni test found that the average differences in the roasting temperature of Arabica coffee were significantly different 160°C-180°C and 160°C-210°C
Adsorpsi Logam Merkuri (Hg) dari Limbah Tanah Tercemar Menggunakan Tanaman Sawi (Brassica juncea L) pada Berbagai Waktu Tanam: Adsorption of Mercury (Hg) from Contaminated Soil Waste Using Sawi Plants (Brassica juncea L) in Various Planting Times
Get PDFMercury (Hg) as a gold extractor can cause environmental pollution, therefore, hyperaccumulator plants are needed, such as mustard greens (Brassica juncea L). Research on the effect of planting time of mustard greens on the adsorption of mercury (Hg) metal ion on contaminated soil waste has been carried out. The purpose of this research was to determine the concentration and adsorption mechanism of Hg metal ion from contaminated soil at roots and canopy of mustard plants at various planting times. Amount of Hg metal ion adsorbed on the roots and canopy of mustard greens at 2, 4, and 6 weeks of planting times were analyzed using Atomic Absorption Spectrophotometry (AAS). The results showed that the average levels of Hg metal ion adsorption at various planting time of 2, 4, and 6 weeks at roots were 156.611 μg/g, 810.256 μg/g, and 888.711 μg/g, respectively, and at the canopy were 69.486 μg/g, 134.580 μg/g, and 60.416 μg/g, respectively. The planting time of 6 weeks resulted in the highest adsorption ability of Hg at the roots. The results of the bioconcentration factor (BCF) test showed that the adsorption of Hg in the roots and canopy of the mustard plant took place using a phytoextraction mechanism (BCF < 1)