Jurnal Akademika Kimia
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Synthesis and Characterization of Activated Carbon from Waste Compedak Fruit (Artocarpus Champeden) Activated H3PO4 as Adsorbent of Methylene Blue
Get PDFSynthesis of activated carbon from cempedak peel waste is carried out to utilize biomass waste. This study aimed to synthesize and characterize activated carbon from cempedak peel waste. The synthesis was carried out by chemical activation using phosphoric acid with a dry impregnation ratio of 1:4 (g sample:g H3PO4). Samples impregnated for 24 hours were then heated at 250℃—and then calcined at 350℃ and 450℃. The XRD and FTIR characterization results indicated that the activated carbon obtained had an amorphous structure and the activated carbon obtained had hydroxyl, carbonyl, and carboxylic groups. Activated carbon with the highest yield was obtained at a temperature of 350, namely 43%. The results of determining the water content of activated carbon obtained are 8.36% at 350 0C and 7.1% at 450 ℃. The value of water content and ash content of activated carbon from the skin of this cempedak fruit has met the Indonesian National Standard (SNI 06-3730-1995). The best-activated carbon yield was at a calcination temperature of 450, with the percentage of adsorption efficiency on methylene blue of 98.88%
Analysis of Water Quality and Pollution Index at Karangantu Fishing Port Area, Banten
Get PDFKarangantu fishing port symbolizes the rapid fishing industry in Serang, Banten. So many activities in the Karangantu fishing port area, such as a place for landing fisherman’s boats, shipping fish catches, and tourism object. These activities may impact the water quality. This research aims to analyze the water quality and pollution index in Karangantu fishing port. The water sample was carried out by purposive sampling in three stations around the Karangantu fishing port area: the estuary area, the fish auction, and the dock. Twelve parameters were analyzed: temperature, turbidity, transparency, TDS, TSS, pH, DO, COD, nitrate, cadmium, lead, and total coliforms. The water quality analysis result was compared by Class III water classification based on PP RI Nomor 82. Water quality was determined by the pollution index based on the minister of environment decree No. 115/2003. The result indicates that the estuary area is polluted, with a PIj score of 6.35; the fish auction and the dock f are in the moderately polluted categories, with PIj scores of 4.99 and 3.90. The worse pollution can be prevented by raising public awareness about the importance of clean water and providing waste management facilities
Comparison of the Composition of Cinnamomum verum J. Presl and Zingiber officinale Roscoe to the IC50 Value
Get PDFAntioxidants are substances that can reduce and prevent free radical damage or prevent oxidative damage. The combination of two or more plant species can result in a greater potential for antioxidant activity. The purpose of this study was to determine the IC50 value of the combination of Cinnamomum verum J. Presl and Zingiber officinale Roscoe with a ratio of 1:2, 1:1, and 2:1. Antioxidant activity was determined by the amount of DPPH absorption inhibition (% Inhibition) and the value (50% Inhibition Concentration). The IC50 value in antioxidant activity measurement of ethanol extract combination of Cinnamomum verum J. Presl and Zingiber officinale Roscoe in the ratio of 1:2, 1:1, and 2:1, was 372.3078 ppm, 354,3077 ppm, and 344.0863 ppm respectively. The ethanol extract of Cinnamomum verum J. Presl and Zingiber officinale Roscoe at a ratio of 2:1 was the best combination with total phenolic content of 5.63 mgGAE/100 g and produced an IC50 value of 344.0863 ppm
Characterization of Natural Clay from Gowa Regency, South Sulawesi Province, Indonesia
Get PDFClay is one of the essential natural minerals in human life, especially in the industrial sector, which is widely used as a raw material for ceramics fabrication, adsorbents, and photocatalysts. The characteristics of clay significantly affect the quality of the resulting material. This study will study the aspects of natural clay in Gowa Regency, South Sulawesi Province, without the leaching process and with acid leaching. Acid leaching uses 3 M HCl, previously roasted at a temperature of 600 oC. The characterization consisted of metal oxide analysis using XRF, mineral content analysis using XRD, morphological analysis, and compound content using SEM-EDX. The results showed that the primary metal oxide content in natural clay was Fe2O3, Al2O3, and SiO2, the content of Fe2O3 decreased after the raw clay was treated with acid. The main mineral content in the sample is quartz, kaolinite, and hematite. The sample's morphology looks different after being given acid treatment; the acid leaching natural clay sample shows a porous morphology, while the natural clay without acid leaching shows the morphology in the form of lumps. The EDX mapping analysis showed that the number of impurities decreased after being given acid treatment
Synthesis and Characterisation of B-CDs/TiO2 Composite
Get PDFSynthesis of composite boron-doped carbon nanodots (B-CDs)/TiO2 using the sol-gel method performed with titanium tetraisopropoxide (TTIP) precursor and B-CDs prepared by the microwave method using citric acid monohydrate, urea, and boric acid as precursors. The optimum concentration of boron dopant (B) on B-CDs/TiO2 is 0.5% boron (w/w) which is then used as a composite on TiO2 resulting in a brown solid and has blue luminescent under UV light. The result with UV-Vis/DRS for variation in B-CDs concentration of 0.5%, 1.25%, and 2.5% showed Eg values of 2.34 eV, 2.00 eV, and 2.29 eV. B-CDs cause the maximum emission peak (λEm) to redshift and affect the intensity of photoluminescence TiO2. The characterization of FT-IR does not indicate a new peak, there is no bonding in the B-CDs/TiO2 composite. The TiO2 diffractogram was observed to shift towards a larger 2θ which caused the crystallinity of TiO2 to decrease. Based on the photocatalytic activity test on the degradation of methylene blue solution, it showed fairly good activity. It is expected that the B-CDs/TiO2 composite has the potential to be applied as a photocatalyst to degrade organic pollutants under visible light illumination
Evaluation of the Addition of Eugenol of Clove Leave Essential Oil in the Ration on Phenol and Antioxidant Levels of Male Laying Hens Meat
Get PDFEugenol is a component of phenol, biologically it can function as an anti-bacterial, anti-fungal, insecticide, and antioxidant. The content of eugenol which is quite large in clove leaf essential oil is used as a bioactive substance to increase antioxidant levels in meat. Experimental by using 100 male laying hens were then placed into 20 cage units, each cage unit filled with 5 experimental chickens. Meat sample collection for analysis of phenol and IC50 levels was carried out by slaughtering experimental chickens at 8 weeks of age. Samples of chicken meat were taken from the breast of each experimental animal as much as 100 grams. Determination of the total phenol content of chicken meat using Folin-Ciocalteu with gallic acid as a comparison, while the antioxidant activity testing using the DPPH free radical absorption method. In this experiment, eugenol was added to the basal ration with 5 treatments, namely: E0 = without eugenol; E1 = 0.5% eugenol; E2 = 1% eugenol; E3 = 1.5% eugenol; E4 = 2% eugenol. The variables observed were phenol levels and IC50 values which can describe the antioxidant power in male laying hens. The results showed that the addition of clove leaf eugenol as an additive in the ratio had a very significant effect (p < 0.01) on phenol levels and IC50 values. male laying hens. Each increase in the use of 0.5% eugenol in the ration can increase the phenol content and decrease the IC50 value significantly in the meat produced. The level of eugenol in the ration was positively correlated with the levels of phenol and antioxidants in the meat of laying hens, while the levels of eugenol in the ration and the levels of phenol in the meat had a negative correlation with the IC50 value of the meat of laying hens
Utilization of Papaya and Pandan Leaf Extract as a Source of Vegetable Pesticides
Get PDFIn this study, the manufacture of vegetable pesticides using natural ingredients of papaya leaf extract and pandan leaf extract has been carried out as a substitute for synthetic pesticides to kill plant pest organisms (OPT). This research was an experimental study using 250 experimental organisms Larvae of Spodoptera litura which were divided into 5 groups. Each group consisted of 10 larvae of Spodoptera litura. Each group was repeated 5 times. As test materials, papaya leaf extract and pandan leaf were added to the media solution containing the test organisms. The concentration of each extract was different for each treatment in each vial, for P1 (Papaya Leaf) which was 150 ml, P2 (Pandan Leaf) 150 ml, and P3 300 ml (Mixture of Papaya Leaves and Pandan Leaves), and Control was 0ml. Data were obtained by counting the number of larvae that died on the first day after application. Based on the data, the percentage value of larval mortality was calculated using the Percentage formula, while the percentage value of larval mortality in the control treatment was calculated using the Abbott formula, the average value of mortality for each replication was calculated using the Datum formula. Based on the testing of vegetable pesticides from papaya leaf extract and pandan leaf extract, the characteristics of vegetable pesticide products from papaya leaf extract and pandan leaf extract were obtained, with the highest mortality percentage obtained in P3 treatment (a mixture of papaya leaf extract and pandan leaf extract) of 88%, while the percentage of mortality was 88%. in treatment P1 (pawpaw leaves) by 70%, and the percentage value of death in treatment P2 (pandan leaves) by 38%. From these results, papaya leaves and pandan leaves are effectively used as sources of environmentally friendly vegetable pesticides in killing plant pests of Spodoptera litura larvae
Enhancement Mechanical Properties of Simalambuo Wood (Loppophetalum spp) Delignified using NaOH in The Thermomechanical Densification Method
Get PDFOne of the problems with fast-growing wood is the low density, which causes poor mechanical properties, so a densification process is carried out to increase the wood's density, surface hardness, and strength. In this study, the delignification process using NaOH was carried out at variations of 12.24, and 48 hours and then continued with the thermomechanical densification process. This study decreased lignin content in delignification simalambuo wood from 30% to 4%. The value of the Modulus of Rupture, Modulus of elasticity, and surface hardness increases with increasing immersion time during the delignification process. The highest values of Modulus of Rupture, Modulus of elasticity, and surface hardness were obtained by simalambuo wood soaked for 48 hours, namely, 2828.23 kg/cm2, 97.47 kg/cm2, and 256.73 kg/cm2
The Extraction of Nickel from Morowali Laterite Ore with Nitric Acid
Get PDFNickel extraction from Morowali laterite ore has been carried out with nitric acid as the solvent. This study aims to determine the effect of nitric acid concentration, temperature, and stirring time on nickel content in laterite ore originating from Morowali. Morowali laterite seeds were extracted using the leaching method using nitric acid as the solvent with various concentrations of 0.5, 1, and 2, temperatures of 30, 60, and 95, and stirring times of 3, 6, and 12. Taguchi analysis was used in this study to obtain the effect of the three parameters used. The results showed that the optimum conditions were obtained at a concentration of 2 molars nitric acid, a temperature of 95°C, and a stirring time of 12 hours, with a nickel content of 16.469 ppm and a nickel recovery percent of 3.88%
Analysis of the Ability to Understand the Basic Law of Chemistry for Science High School Students
Get PDFThis study aimed to describe the student's capability of grade XI Science at SMA 3 Palu in understanding Fundamental Chemical Laws. This study was a qualitative descriptive study. The sample was students in the class XI Science 7, which amounted to 29 students, and XI Science 8, which amounted to 31 students. The sample was determined based on nonprobability sampling with a purposive technique based on the suggestions from the chemistry teacher that the two classes were homogeneous. Data were obtained from the test of students' understanding of fundamental Chemical Laws consisting of six essay questions and supported by the interview results. Respondents for the interview were six students based on the categorization of high, medium, and low scores, which were obtained from the calculation of the average score of students and standard deviation. The results showed that the capability on understanding Fundamental Chemical Laws of students of grade XI Science at SMA 3 Palu which was included in the high category was the ability to interpret as much as 79.58%, and included in the sufficient category was the ability to classify as much as 56.25%, while those included in the low category was the ability to exemplify, conclude, compare, and explain, with successive as much as 30, 24.58, 32.08, and 40.42%, respectively