KOVALEN: Jurnal Riset Kimia
Not a member yet
324 research outputs found
Sort by
Penggunaan Sabut Kelapa Teraktivasi NaOH sebagai Adsorben Metilen Biru: Utilization of Coconut Fiber NaOH-Activated as Blue Methylene Adsorbent
Full text linkMethylene blue is a textile dye with carcinogenic and mutagenic properties which can cause various problems for the environment and organisms, therefore it is necessary to treat the waste. This study describes the adsorption of methylene blue using base-activated coconut coir. Coconut coir as waste was prepared into 80 mesh-sized powder and then activated using NaOH solution. The base-activated coconut fiber was then used for methylene blue adsorption under several optimization conditions such as pH, contact time, concentration, and adsorption isotherm. The determination of methylene blue was adsorbed by the adsorbent measured using UV-VIS. The pH and contact time results were 7 and 75 minutes, respectively, with the adsorption capacity (qe) of 1.98 mg g-1 and 99.91%. The isotherm adsorption of blue methylene followed the Langmuir isotherm model with the maximum adsorption capacity (Qmax) of 0.2 mg -1. The result showed that the coconut fiber base activated could be used as a dye adsorbent
Analisis Kadar Kadmium (Cd) dalam Bawang Merah Lokal Palu (Allium cepa L. var. aggregatum) pada Berbagai Lokasi dan Umur Tanam: Analysis of Cadmium (Cd) in Palu Local Shallots (Allium cepa L. var. aggregatum) at Various Locations and Planting Ages
Full text linkThe local Palu shallot (Allium cepa L. var. aggregatum) plant is one of the leading products in the Central Sulawesi region. Shallots can experience a decrease in quality if they are contaminated with heavy metals, such as cadmium (Cd) in amounts that exceed the threshold. This study aims to determine the effect of planting age on cadmium levels in local Palu shallots cultivated in Oloboju Village and Solove Village, Biromaru District, Sigi Regency. The research variables used were the planting age which consisted of 4 levels (age 40, 50, 60, and 70 days), and the planting location which consisted of 2 levels (Solove Village and Oloboju Village). Cd levels were analyzed using an Atomic Absorption Spectrophotometer (AAS). Cadmium levels in shallot roots at two planting locations decreased with increasing planting age, from 101.34 - 107.18 mg/kg at 40 days of age to 1.68-3.78 mg/kg at 70 days of age. Shallot bulbs at two locations had lower cadmium levels than roots, namely 0.01-0.04 mg/kg. The results of the study found that planting time had a significant effect on cadmium levels in the roots of shallots, but planting age and planting location had no significant effect on cadmium levels in local Palu shallot bulbs with levels that met the SNI (Indonesian national standard) quality requirement
Produksi Konsentrat Protein dari Ampas Kelapa (Cocos nucifera L.) Menggunakan NaOH dan (NH4)2SO4 : Production of Protein Concentrate from Coconut Pulp (Cocos nucifera L.) using NaOH and (NH4)2SO4
Full text linkCoconut pulp wasted from processed coconut oil has a protein content of up to 18.20%. The potential coconut pulp protein can be processed in protein concentrate which has many benefits. This research was conducted to determine the effect of NaOH and (NH4)2SO4 concentrations in isolating protein and producing protein concentrates that have the highest yield and protein content. Isolation of coconut pulp protein was carried out using NaOH at several concentrations, namely 0, 0.2, 0.4, 0.6, 0.8, and 1 M, while the protein concentrate was prepared using the salting out method with a saturation level of the ammonium sulfate salt of 55%, 60%, and 65%. Analysis of protein content was carried out using the Kjeldahl method. The use of NaOH 0.2 M and (NH4)2SO4 with a saturation level of 60% was the chosen treatment with crude protein content and yield of 75.63% and 33.83%, respectively
The Effect of Solvent-to-Coffee Ratio on Caffeine Content in Ethyl Acetate Extracts of Arabica Gayo Coffee Beans
Full text linkThis paper studies the optimal ratio that gives the highest caffeine amount and improves the efficiency and quality of extraction from Arabica Gayo coffee beans. No previous studies have explored the best ratio of Gayo Arabica coffee beans to ethyl acetate solvent for extracting caffeine. The paper explains the method used, which has four main steps: preparing materials, extracting and measuring caffeine, and analyzing the results. The paper presents the experimental findings and discusses how different ratios affect caffeine content in Arabica Gayo coffee beans. It uses statistics to show significant differences between the ratios and compares them using Tukey tests. The paper concludes that the best solvent-to-coffee ratio for maximizing caffeine in ethyl acetate extracts is 1:5, resulting in a concentration of 1411.1 ppm. This ratio gives the best balance between caffeine yield and solvent usage
Total Metabolit Sekunder dan Uji Aktivitas Antioksidan Daun Juwet (Syzygium cumini L.) dengan Spektrofotometer Uv-Vis: Total Secondary Metabolites and Test of Antioxidant Activity of Juwet Leaves (Syzygium cumini L.) with Uv-Vis Spectrophotometer
Full text linkThe aim of this research is to determine the total amount of secondary metabolites (alkaloids, flavonoids, saponins and tannins) contained in the ethanol juice of juwet leaves (Syzygium cumini L.) using the UV-Vis spectrophotometry method and to determine the antioxidant activity of the ethanol juice of juwet leaves based on IC50 value. Determination of total levels of secondary metabolites using UV-Vis spectrophotometry and antioxidant testing using the DPPH method. The results of qualitative analysis of the ethanol juice of juwet leaves contained secondary metabolite compounds, namely flavonoids, saponins, tannins and alkaloids. The average value obtained for the level of total secondary metabolites for flavonoid compounds was 0.417% w/w., saponins 0.766 w/w., tannins 0.282 w/w and alkaloids 0.384% w/w. The results of testing the antioxidant activity of juwet leaf ethanol extract and quercetin as a comparison had antioxidant activity, the average IC50 results were 14.289 ± 0.255 ppm and 102.45 ppm, therefore they were classified as moderate antioxidants
Sintesis dan Uji Kinerja Membran Selulosa Termodifikasi Polistirena dari Ampas Tebu dengan Aditif Monosodium Glutamate untuk Menurunkan Nilai BOD dan COD Limbah Cair Tahu: Synthesis and Performance Testing of Modified Cellulose Membrane with Polystyrene Derived from Sugarcane Bagasse and Monosodium Glutamate Additive for Decreasing BOD and COD Values in Tofu Wastewater
Full text linkTofu liquid waste, which has high BOD and COD values, can contaminate waters if it is directly disposed of without prior treatment. Therefore, waste treatment is necessary before being released into water. One method for treating this waste is by using a cellulose acetate membrane. In this research, a cellulose acetate membrane was synthesized from sugarcane bagasse fibers using the phase inversion method. The membrane was added 6% MSG as an additive to improve its performance. The membrane was applied to treat tofu waste with BOD and COD parameters. The membrane’s flux values obtained in this study were 33.56 L/(m².hour) for water and 26.85 L/(m².hour) for tofu liquid waste. SEM test result showed that the membrane with a 6% MSG additive had more pores and a denser surface compared to the membrane without the additive. The membrane was capable of decreasing BOD and COD values by 62.5% and 75.3% respectively in liquid tofu waste
Pembuatan dan Karakterisasi Kertas Kemasan Berbasis Ampas Kunyit dan Jahe Merah dengan Variasi Konsentrasi Natrium Hidroksida: Preparation and Characterization of Packaging Paper Based on Turmeric and Red Ginger Pulp with Varying Concentrations of Sodium Hydroxide
Full text linkThe production of herbal beverages such as ginger, turmeric, and other spices generates waste that is commonly discarded. The cellulose content in red ginger is about 60-80%, and in turmeric, it is 50%. The high cellulose content makes red ginger and turmeric waste suitable for use as raw materials for paper production. The objective of this research is to determine the optimum conditions for making paper based on red ginger and turmeric waste. The pulp formation process was carried out using the Semi-Mechanical Method, which involves the addition of chemical solutions and grinding, on a mixture of turmeric and red ginger waste (60:40) with variations of NaOH concentration at 8%, 10%, and 13% (w/v). The papermaking process began with refining and drying the waste, cooking the pulp, adding water and kaolin filler, and then printing. Characterization included antibacterial testing, tensile strength, and grammage. Based on the pulp characterization results at the optimum NaOH concentration of 8%, the moisture content was 8.89%, cellulose content was 49.28%, and lignin content was 9.28%. These parameters comply with the national standard (SNI) for packaging paper. The paper characterization results showed a tensile index of 2.12 Nm/gram, an antibacterial inhibition zone of 5 mm, and a grammage of 13 g/m2. This research indicates that the NaOH concentration influences the moisture, cellulose, and lignin content. Furthermore, based on the characterization results, paper made from turmeric and ginger waste has the potential to be used as antimicrobial packaging paper
Analisis Kadar Kurkumin pada Herbal Oil Kunyit Ekstrak Virgin Coconut Oil dengan Metode Ultrasonik dan Maserasi: Analysis of Curcumin Levels in Turmeric Herbal Oil Extract Virgin Coconut Oil with Ultrasonic and Maceration Methods
Full text linkVegetable oil theoretically and experimentally has proven its potential as an alternative solvent in the extraction of natural materials. Turmeric infused with virgin coconut oil (VCO) is a way to take advantage of the active compounds from the herbs and the oil itself. This study aims to determine the ability of the VCO solvent in extracting curcumin compounds from turmeric with the addition of tween 80 surfactants. The extraction method used was maceration at 60℃ and an ultrasonic frequency of 40 kHz for 15 minutes. Thin layer chromatography (TLC) was used for qualitative analysis of each herbal oil extract using chloroform: methanol (95:5) eluent and FTIR spectrophotometer to identify functional groups. The highest curcumin content was found in herbal oil with tween 80 of 2 ml, namely 31 ppm in maceration extraction and 260.7 ppm in ultrasonic extraction. Identification of curcumin functional groups in herbal oils showed absorption patterns of O-H, C=O, aromatic C=C, C-O-C, and C-H
Studi Awal Sintesis ZnO/SiO2 dengan Silika dari Limbah Padat Geothermal dan Uji Performansinya dalam Penghilangan Metilen Biru : Preliminary Study of ZnO/SiO2 Synthesis with Silica from Geothermal Solid Waste and Its Performance Test in Methylene Blue Removal
Full text linkIndustrial development impacts environmental problems, such as the emergence of wastewater containing methylene blue. In this research, SiO2 was composited with ZnO to remove methylene blue. The steps of this study include SiO2 extraction from geothermal solid waste, ZnO/SiO2 synthesis, and methylene blue removal test. The process of extracting SiO2 from geothermal solid waste used the sol-gel method. The FTIR analysis showed that SiO2 contains siloxane group (Si-OH) and silanol group (Si-O-Si). ZnO/SiO2 synthesis was done by making SiO2 suspension and continued with adding the addition of several Zn(NO3)2.6H2O. The FTIR analysis of ZnO/SiO2 showed no absorption at the wavenumber 960 cm-1 and there is a shoulder around the number 950 cm-1 which indicates the vibration of Si-O-Zn. Meanwhile, methylene blue removal tests were carried out on artificial wastewater. Based on the research results, the highest percent removal (99%) was obtained under operating conditions, including a dose of 500 mg/L, pH 10, and contact time of 30 minutes. Based on box-benkhen analysis, it is known that dose and pH singularly affect the percent removal, while contact time does not affect the percent removal. The optimization results obtained optimum conditions for methylene blue removal at a dose of 581.952 mg/L, pH of 10, and contact time of 30 minutes. Percent removal in conditions without irradiation and with irradiation of UV light were 98.758% and 99.178%. It shows that the adsorption process is the main process in removing methylene blue, while the photocatalytic process has little effect because it is possible that only a small amount of ZnO can attach to the surface of SiO2
Isotermal Adsorpsi Ion Tembaga (II) Menggunakan Arang Tongkol Jagung (Zea mays L.) Teraktivasi Kalium Permanganat: Isothermal Adsorption of Copper (II) Ions Using Charcoal from Corn Cobs (Zea mays L.) Activated by Potassium Permanganate
Full text linkCorn cobs which generally only become waste can be processed into activated carbon and used for the absorption of heavy metals, such as copper(II) ions. This study aims to determine the morphology of corn cobs charcoal after activation, determine the isothermal adsorption model of copper (II) metal ions on corncob-activated carbon, and then determine the adsorption capacity of copper (II) metal ions on corncob-activated carbon. The morphology of the corncob-activated charcoal obtained was analyzed using Scanning Electron Microscopy (SEM). Isothermal adsorption of copper (II) ions was carried out with various concentrations of copper (II) ions of 5, 10, 20, 50, and 100 ppm. The results of the analysis using SEM showed that the surface shape of the corncob-activated charcoal is regular and has pores with a pore diameter obtained in the range between 1.08-1.26 m and 1.38-1.59 m. The mechanism of adsorption of copper (II) ions by corncob-activated charcoal using KMnO4, following the Freundlich isothermal model with a value of R2 0.9993 with an adsorption capacity of 51 x 10-4 mmol/L. The utilization of activated carbon from corn cobs that are activated by potassium permanganate is very effective for adsorbing copper metal ion pollutants through an adsorption mechanism on the surface of activated carbon