KOVALEN: Jurnal Riset Kimia
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Reduksi Kandungan Zat Aktif Anionik dalam Limbah Laundry dengan Memanfaatkan Kombinasi Zeolit dari Tongkol Jagung dan Pseudomonas aeruginosa: Reduction of Anionic Surfactant Content in Laundry Wastewater by Utilizing a Combination of Zeolite from Corn Cobs and Pseudomonas aeruginosa
The increasing environmental pollution is one of the consequences of human activities that continue to expand. The environment has limitations in coping with pollutants generated by humans, such as waste from the laundry industry. This research aims to evaluate the combined effect of zeolite produced from corn cobs and the use of microorganisms capable of degrading anionic surfactants, with the goal of reducing the concentration of anionic surfactants in laundry wastewater. The methods used include adsorption using corn cobs as adsorbents and biodegradation using surfactant-degrading bacteria. Morphological observations using Scanning Electron Microscope (SEM) indicate that the produced zeolite has a crystal structure that stacks up like clumps of cubes. X-ray Diffraction (XRD) analysis shows that zeolite synthesized with a silica extraction ratio from corn cobs and sodium aluminate of 20:20 mL has been successfully conducted. The biodegradation process of anionic surfactants in laundry wastewater using a combination of synthesized zeolite and Pseudomonas aeruginosa bacteria employing the Methylene Blue Alkyl Substance (MBAS) method has shown a decrease in concentration to 1.66 mg/L and degradation of 33.55%, especially in sample 3 with variations of 7.5 grams of corn cob zeolite and 15% microorganisms, during a 5-day experiment
Sintesis dan Karakterisasi Zeolit X dari Fly Ash Batu Bara Menggunakan Metode Sintesis pada Suhu Rendah: Synthesis and Characterization of Zeolite X From Fly Ash Waste Using Synthesis Method at Low Temperature
Many industries in Indonesia have switched to using coal fuel. The use of coal at PT PLTU Paiton has reached 250 tons per hour and produces 4% of waste by-products of combustion contained from bottom ash by 25% and fly ash by 75%. Fly ash waste will harm the environment and health. Fly ash contains many components, including SiO2 52%, Al2O3 31.86%, Fe2O2 4.89%, CaO 2.68%, and MgO 4.66%. This research aims to synthesize and characterize zeolite X from PT Paiton fly ash using a low-temperature synthesis method. Zeolite X synthesis in this study has 3 steps: The pretreatment process, silica synthesis process, and zeolite synthesis process. The results of silica synthesis obtained SiO2 55.54%. The resulting zeolite product has a typical peak at 2Ï´ 28.72. Zeolite x has a wavelength of 430, 570, 695,7, and 965,7, which respectively indicates Si-O-Si and Si-O-Al bonds, double ring bonds, T-O ring symmetric strain (internal), and asymmetric (internal). The results of zeolite X crystal synthesis in this study could not be formed in the variable of adding time of 3-5 hours with a variation of moles of Al2O3 0,5-1,5 moles
Fitoremediasi Air Tercemar Nikel (Ni) dan Merkuri (Hg) Menggunakan Tanaman Azolla filiculoides Lam.: Phytoremediation of Nickel and Mercury Contaminated Water Using Azolla filiculoides Lam.
Water pollution from settlements, agriculture, and industry is a significant issue, as it introduces pollutants like heavy metals into water bodies, harming both humans and aquatic ecosystems. Phytoremediation is a cost-effective, eco-friendly technology for reducing heavy metals in water bodies. This study aimed to assess Azolla filiculoides plants' ability to absorb heavy metals nickel and mercury. The plants were grown in a hydroponic solution contaminated with 0.25 ppm of nickel and 0.5 ppm of mercury. The growth of the plants was measured based on their wet and dry weight, and the nickel and mercury content in the plant tissue was analyzed using Atomic Absorption Spectrophotometry (AAS). The study found that the growth of A. filiculoides plants was unaffected by the concentration of either nickel or mercury. The amount of nickel absorbed by the plants was 0 µg/g plant dry weight, while for mercury, it was 1654.82 µg/g. Based on the results, A. filiculoides plant is more promising for use as a phytoremediation agent for water bodies contaminated with mercury heavy metals rather than nickel heavy metals
Sintesis dan Karakterisasi Semikonduktor TiO2 Doping Magnesium dengan Metode Hidrotermal: Synthesis and Characterization of Magnesium Doped TiO2 Semiconductor by Hydrothermal Method
Semiconductors are materials that range between insulators and conductors in terms of conductivity value. Titanium Dioxide (TiO2) is a semiconductor that is widely applied to various things. TiO2 has the benefits, such as being environmentally stable and inexpensive. TiO2 is photoactive in the range of ultraviolet radiation due to the band gap value of 3.2 eV. However, ultraviolet is only produced from 5% of sunlight. The research aimed to narrow the band gap energy so as to maximize light absorption. This is done by modification with the addition of Mg elements to TiO2 materials at different mass variations of Mg (1%, 1.5%, 2%) to the mass of TiO2 which is often referred to as doping. TiO2 was doped by Mg using a hydrothermal method for 24 hours with a temperature of 180áµ’C, followed by 2 hours of calcination at 400áµ’C. Then, TiO2 and Mg-doped TiO2 particles were characterized by SEM-EDX, FTIR, and UV-Vis. Based on the results of TiO2 and Mg-doped TiO2 particle characterization using SEM, both particles are spherical in shape. The success of Mg doping was identified from the data of EDX characterization, which revealed that the mass % of the Mg component increased with the greater Mg doping concentration on TiO2 particles. There was no structural change following Mg doping on TiO2 particles, as evidenced by the same peak based on the results of FTIR characterization of TiO2 and Mg-doped TiO2 particles. Moreover, a 2% Mg mass doping on pure TiO2 resulted in a decrease in band gap energy to 3.16 eV, in which the pure TiO2 was 3.39 eV. The mass doping of Mg on TiO2 required further optimization to obtain the maximum band gap energy reduction for photocatalytic applications
Identifikasi dan Uji Aktivitas Antioksidan Senyawa Metabolit Sekunder Ekstrak Tanaman Cleome viscosa L: Identification and Antioxidants Activity Tests of Secondary Metabolite Compounds of Clome viscosa L. Plant Extracts
Cleome viscosa L. has been used empirically by people on the island to treat diseases that have clinical symptoms such as malaria (fever, sweating, chills, and muscle aches). The purpose of this study was to determine the class of secondary metabolites and antioxidant activity. The extraction was carried out using the maceration method, while the fractionation was carried out using the separating funnel. The secondary metabolites found in the Cleome viscosa L. plant extract are alkaloids, flavonoids, steroids, terpenoids, tannins, and saponins. Antioxidant test conducted by DPPH method showed that the positive control of ascorbic acid and methanol extract obtained IC50 values of 3.86 ppm and 37.4 ppm, respectively
Penentuan Suhu Optimum Pirolisis Serbuk Gergaji Batang Kelapa: Determination of the Optimum Temperature of the Pyrolysis of Coconut Trunk Sawdust Waste
Research has been carried out on the utilization of biomass waste of coconut trunk sawdust using the pyrolysis method to produce two products simultaneously, namely charcoal and liquid smoke. In order to obtain charcoal products with optimum calorific value, it is necessary to understand the optimum pyrolysis conditions. One of the optimum conditions, namely pyrolysis temperature, was studied in this research. Pyrolysis was carried out in a simultaneous pyrolysis reactor at a flow rate of argon inert gas into the reactor of 2 liters/minute and a pyrolysis time of 2.5 hours with pyrolysis temperature variations of 350, 400, 450, and 500°C, respectively. The study showed that the optimum temperature of 400oC was obtained which gave a yield of 34% charcoal with a calorific value of 7229 kcal/kg. Compared to the calorific value of the raw material for coconut sawdust which is 4400 kcal/kg, there was an increase in the calorific value of the pyrolysis product by 64%. Based on the optimum temperature condition, liquid smoke as a by-product was also obtained with a yield of 45%. Charcoal can be used as a solid fuel or as a bioadsorbent in the treatment of liquid waste or clarification of liquid food products such as virgin coconut oil (VCO). Grade 3 liquid smoke can be used as a biopesticide, while grade 1 liquid smoke can be used as a food preservative. Given the benefits of the two pyrolysis products, both of the products from the current research have a promising market value
Formulasi Losion Ekstrak Kopi Robusta (Coffea canephora) sebagai Penangkal Radikal Bebas: Lotion Formulation of Robusta Coffee Extract (Coffea canephora) as a Free Radical Antidote
Hand body lotion is a cosmetic used to moisturize skin in order to reduce dehydration. The coffee extract contains bioactive compounds that can provide high antioxidant activation. The purpose of this research is to study the effect of concentration on coffee extract and the addition of olive oil on organoleptic, hedonic, pH, and dispersive properties and to determine the value of the Sun Protection Factor (SPF) in the lotion. The research method involved extracting coffee grounds, heating the oil and water phases to 65°C, and mixing the two phases till it becomes an emulsion. Then add the oil and water to the mixture. The lotion that’s already in the container is ready for testing. This research used 8 formulas with coffee extract concentrations of 2% and 4%, and variations of olive oil from 0, 1, 2, and 3%. Organoleptic and hedonic tests were tried out on 25 respondents for 2 weeks. The pH test was carried out using a universal indicator. The spreadability test was carried out using a petri dish and the SPF test using a UV-visible spectrophotometer. The results showed that 25 respondents preferred formula 4 over the rest, which was white in color, thick in texture, soft scent and the aftertaste was moisturizing. All formulas have good spreading ability and all in the pH range of 5 – 8. The SPF test results were obtained for each formulation in the range of 6.78 – 12.95 and the highest SPF value was owned by F8 of 12.95
Pengujian Antimikroba, Kelembaban, Tingkat Iritasi, dan Tinggi Busa pada Hand Soap Berbasis Minyak Jelantah dan Zaitun: Testing of Antimicrobial, Humidity, Irritation, and Height of Foam for Hand Soap Based of Used Cooking and Olive Oils
Used cooking oil can disturb health if used continues, and the waste can damage of environment if discarded, therefore prevention is needed through processing (recycling) of used cooking oil to economic products, for example, hand soap. This research was the manufacture of hand soap using the waste of cooking oil, olive oil, and KOH as raw materials. The aim is to determine formulations of raw materials on good hand soap on organoleptic tests, pH, microbial inhibitory zones, humidity and irritation levels, and foam height. The formulations between used cooking oil and olive oil are F1 (125 g and 125 g), F2 (150 g and 100 g), F3 (175 g and 75 g), and F4 (200 g and 50 g). This study begins with the manufacture of hand soap using the experimental method, continued by testing the inhibiting zone of growth of Propionibacterium acne bacteria, moisture content, irritation level, foam height through descriptive tests with analytical observational, organoleptic, and pH. Results are all formulas of hand soap have strong effectiveness in inhibiting microbe growth, distinctive organoleptic, moisturizing, and anti-irritation. The foam height has met with SNI 06-4085-1996, however, the pH value has larger than the pH of SNI 06-4085-1966. The best hand soap preparation is Formula 1 (F1) because it has a pH value that is close to the pH value of SNI
Penurunan Logam Fe dan Co Pada Kerang Hijau (Perna viridis) dengan Metode Perendaman Larutan Belimbing Wuluh: Reduction Fe and Co Metals in Green Mussels (Perna viridis) by Soaking in Starfruit Solution
Green mussels with the Latin name Perna viridis are an animal that lives in the ocean and is a type of shellfish that is widely consumed by the public. Along with time, the emergence of factories that can pollute the oceans can cause contamination of marine life in it, one of the pollutants is the heavy metals of Fe and Co. The accumulation of heavy metals Fe and Co in green mussels can be toxic to people who consume them. This study aims to determine the concentration of heavy metals Fe and Co in green mussels before and after immersion in starfruit solution. Tests for immersion of the starfruit solution were carried out at 15, 30, and 45 minutes, then the destruction results were analyzed using inductively coupled plasma (ICP) with the calibration curve method. The Fe content in the green mussel sample before treatment was 2.946 mg/kg and the Co content in the green mussel sample before treatment was 2.6081 mg/kg. After soaking in starfruit solution for 15, 30, and 45 minutes, the Fe metal was 1.572 mg/kg, 1.275 mg/kg, and 1.035 mg/kg and the Co metal was 1.572 mg/kg, 1.275 mg/kg, and 0.683mg/kg. Research of immersing starfruit solution with soaking for 15, 30, and 45 minutes is effective in reducing levels of heavy metals Fe and Co in green mussels. The highest reduction was observed during a 45-minute immersion, with a decrease of 64.87% for Fe and 73.81% for Co, respectively
Ekstraksi Komponen Lipid dari Mikroalga Nannochloropsis oculata dan Nitzschia sp. dengan Metode Sokletasi dan Bligh Dyer: Extraction of Lipid Components from Nannochloropsis oculata and Nitzschia sp. Microalgae with Soxhletation and Bligh Dyer Methods
Dependence on fossil energy sources as non-renewable energy will trigger the threat of an energy crisis in Indonesia in the future. The solution to this issue is through the development of renewable energy and one of them is through the exploration and utilization of biomass such as microalgae. Microalgae have a high lipid content (4-77%) and have potential as raw materials for producing biofuel (biodiesel, bioethanol, and biogas). Lipids can be converted into biodiesel through acid or base-catalyzed esterification and transesterification reactions. The aim of this research was to determine the percentage of lipid components, namely free fatty acids (FFA), monoglycerides (MAG), diglycerides (DAG), and triglycerides (TAG) from microalgae extracts of Nannochloropsis oculata and Nitzschia sp. using Soxhletation and Bligh Dyer extraction methods. This research also aims to determine the comparison of lipid yields from the two extraction methods. Lipid yield percentage was determined through gas chromatography analysis. The research results showed that the percentages of FFA, MAG, DAG, and TAG for N. oculata ranged from 3.34 - 33.79% (soxhletation) and 0 - 17.54% (bligh dyer). Meanwhile, for Nitzschia sp., the percentage ranged from 7.16 - 26.28% (soxhletation) and 0.45 - 13.73% (bligh dyer). Lipid yield for N. oculata was 1.81% (soxhletation) and 2.21% (bligh dyer), while for Nitzschia sp., 0.96% (soxhletation) and 2.10% (bligh dyer). Based on the results of both extraction methods, it was found that the total lipid percentage of the microalgae N. oculata was higher than Nitzschia sp