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KOVALEN: Jurnal Riset Kimia
Published by Universitas Tadulako
ISSN : -     EISSN : 24775398     DOI : https://doi.org/10.22487/kovalen
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry
KOVALEN: Jurnal Riset Kimia is a peer-reviewed journal of chemistry published by the Tadulako University, Indonesia. This journal concern with publishing the original research articles, review articles, and the current issues related to chemistry. Publishing frequency 3 issues per year, in April, August, and December.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 9 Documents
 1 
Search results for , issue "Vol. 10 No. 3 (2024): December Edition" : 9 Documents clear
Induksi Aquilaria malaccensis Menggunakan Kombinasi Fusarium oxysporum dan Asam Salisilat: Aquilaria malaccensis Induction Using a Combination of Fusarium oxysporum and Salicylic Acid Rani, Diah Puspa; Jayuska, Afghani; Khotimah, Siti; Ardiningsih, Puji; Agus Wibowo, Muhammad
KOVALEN: Jurnal Riset Kimia Vol. 10 No. 3 (2024): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2024.v10.i3.17041

Abstract

Agarwood is a resin from agarwood-producing plants that are given certain stimulants, thus stimulating the tree's defense system. The defense system produced is in the form of a sweet-smelling phytoalexin compound, better known as agarwood. Stimulants that can stimulate the formation of Gaharu are biological inoculants and chemical inducers. In this research, the biological inoculant used the Fusarium oxysporum fungus, and the chemical inducer used salicylic acid. This research aims to determine the effectiveness of using a combination of Fusarium oxysporum and salicylic acid in producing agarwood resin. The combination treatment of Fusarium oxysporum and salicylic acid was carried out using the injection method on Aquilaria malaccensis tree branches, and induction was carried out for 3 months. This research shows that the TLC test results in all treatments contain aloes, which is proven by the discovery of phenolic and terpenoid compounds. The combination treatment produces a color change intensity that is not darker and has a broader color change zone compared to the single treatment. Therefore, it can be concluded that the combination of Fusarium oxysporum and salicylic acid is less effective in producing Gaharu than the single treatment.
Pemanfaatan Limbah Tandan Kosong Kelapa Sawit dan Kulit Jagung Manis menjadi Kertas Karton menggunakan Metode Organosolv: Utilization of Empty Fruit Bunch and Sweet Corn Husk Waste into Paperboard using the Organosolv Method Ramayanti, Cindi; Sari, Winda Febrina; Mustain; Oktaviani, Erika Dwi; Mujiyanti, Apri
KOVALEN: Jurnal Riset Kimia Vol. 10 No. 3 (2024): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2024.v10.i3.17358

Abstract

Paper is generally made using cellulose, which comes from wood, as raw material. However, if wood is used without stopping, it will cause global temperatures to rise and depletion of wood resources. One alternative to replacing wood in paper production is to use empty fruit bunch (EFB) waste and sweet corn husks. This research aims to obtain optimum conditions from variations in the ratio of raw materials and cooking process solutions and to obtain cardboard paper quality under SNI 0123:2008. The method used in this research is raw material preparation, and the pulp-making process uses the organosolv method. From the results of this research, the characteristics of pulp and paperboard obtained under optimum conditions at a raw material ratio of 30:70% w/w with a cooking solution ratio of 30:50:20% v/v have a cellulose content of 60% w/w, a tensile index of 5 .83 kN/m, absorption capacity 2.35 gr/m2, and grammage 428.67 gr/m2. From these data, it can be concluded that cardboard paper is produced from EFB raw materials and sweet corn husks with a raw material ratio of 30:70 %w/w and a cooking solution ratio of 30:50:20 %w/w using the process organosolv has met SNI 0123:2008 standards on tensile index, absorption capacity and grammage regarding the quality requirements for paperboard.
Pemanfaatan Limbah Puntung Rokok sebagai Inhibitor Korosi pada Baja St40 Menggunakan Metode Microwave Assisted Extraction (MAE) di Lingkungan NaCl 3,56%: Utilization of Cigarette Butts Waste as Corrosion Inhibitor on St40 Steel Using Microwave Assisted Extraction (MAE) Method in 3.56% NaCl Environment Alatif, Ikhsan Akmal; Permatasari, Rahma Puspa; Nurulgina, Rahma; Adzkia, Zahrotul Filza; Andayani, Puri; Putri, Sabrina Aisyah; Adinda; Trirahayu, Dhyna Analyes; Hadiningrum, Kunlestiowati
KOVALEN: Jurnal Riset Kimia Vol. 10 No. 3 (2024): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2024.v10.i3.17394

Abstract

Corrosion is a problem that occurs in many industries and causes large losses. The use of corrosion inhibitors is one way to reduce or inhibit corrosion. Cigarette butt waste extract can be utilized as an organic corrosion inhibitor. This study aims to determine the yield of cigarette butt waste extract, the content of cigarette butt waste extract produced using the MAE method qualitatively, determine the optimum conditions for the extraction process with the MAE method based on variations in microwave power of 150 and 300 watts and calculate the efficiency of corrosion inhibitors and the effect of compounds contained in cigarette butt waste extract in 3.56% NaCl environment. The optimum MAE condition was 150 watts and 15 minutes, with an extract yield of 54.38%. Based on the GC-MS test, it is known that cigarette butts waste extract contains alkaloid, terpenoid, and phenol compounds as corrosion inhibitor compounds. Based on corrosion inhibitor testing, the addition of cigarette butt waste extract corrosion inhibitors can suppress or reduce the corrosion rate that occurs on metals with an inhibitor efficiency of 79.19% in non-aerated conditions and 71.53% in aeration with an inhibitor concentration of 1000 ppm in a 3.56% NaCl environment.
Aplikasi Edible Coating Albedo Semangka dengan Penambahan Ekstrak Etanol Daun Bandotan pada Tomat Napu: Application of Edible Coating of Watermelon Albedo with the Addition of Ethanol Extract of Bandotan Leaves on Napu Tomato Lutfi, Mohammad; Wulandari, Asri; Fito; Rahmadina, Hizra Nur; Chaedar, Nur; Nurhaeni; Amar, Aini Auliana
KOVALEN: Jurnal Riset Kimia Vol. 10 No. 3 (2024): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2024.v10.i3.17408

Abstract

One of the causes of food waste is due to the lack of post-harvest handling of fruits or vegetables, therefore, an innovation is needed to overcome this problem, one of which is with edible coating. This study aimed to determine the characteristics of edible coatings from watermelon albedo pectin with the addition of Bandotan leaf extract as an antibacterial against Napu tomatoes. This study used a completely randomized design (CRD) consisting of 4 treatments, namely tomatoes (edible coating), tomatoes (edible coating + 12.5% bandotan leaf ethanol extract), tomatoes (edible coating + 25% bandotan leaf ethanol extract), and tomatoes (edible coating + 50% bandotan leaf ethanol extract). The watermelon albedo pectin characterization test results were the equivalent weight of 558.3 mg, methoxyl content of 6.1%, galacturonic acid content of 32.1%, moisture content of 11.469%, and ash content of 9.378%. From the results of tomato characterization tests for weight loss, moisture content, and microbial tests, the best treatment was produced by tomatoes (edible coating + 50% antibacterial), with consecutive results of 7.90%, 53.18%, 16.6 colonies (10-4 dilution), and 5.6 colonies (10-5 dilution).
Sintesis dan Karakterisasi Katalis Bentonit Termodifikasi TiO2 dan Terinpregnasi Logam Ni : Synthesis and Characterization of TiO2 Modified Bentonite Catalyst and Ni Metal Impregnated Mirzan, Mohamad; Duda, Nining Austi; Khairuddin; Nurakhirawati; Ruslan
KOVALEN: Jurnal Riset Kimia Vol. 10 No. 3 (2024): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2024.v10.i3.17411

Abstract

TiO2-modified and Ni-impregnated bentonite catalysts have been synthesized and characterized to determine their physicochemical properties. Ni(NO3)2.6H2O was used as a precursor for impregnation. The physicochemical properties determined include surface acidity by acid-base titration method, FTIR spectrum, and XRF and XRD data. The highest surface acidity value was obtained from the Ni-TiO2/bentonite catalyst sample of 1.57 mmol/g. The results of FTIR analysis showed that the peak at wave number 3441 cm-1 in TiO2/bentonite shifted to 3458 cm-1 in Ni-TiO2/bentonite. The distribution of bentonite content after being pillared with TiO2 = 8.68% and impregnated with NiO = 0.58%. The success of nickel metal impregnation into the TiO2/bentonite support was obtained from XRD data, which was marked by the appearance of a typical Ni peak at 2θ = 37.70° d = 2.38 Å, 2θ = 39.39° d = 2.28 Å, 2θ = 43.02° d = 2.10 Å, 2θ = 51.38°d = 1.77 Å.
Sintesis dan Karakterisasi Komposit Mn-N-TiO2/Bentonit untuk Degradasi Polutan Organik: Synthesis and Characterization of Mn-N-TiO2/Bentonite Composite for Organic Pollutants Degradation Ruslan; Prismawiryanti; Sumarni, Ni Ketut; Ridhay, Ahmad; Riski, Mutiara Zalfa; Nurhalisa, Sitti; Marsela, Anggi
KOVALEN: Jurnal Riset Kimia Vol. 10 No. 3 (2024): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2024.v10.i3.17502

Abstract

Research has been conducted on the synthesis and characterization of Mn-N-TiO2/Bentonite composites for the degradation of organic pollutants. This study aims to synthesize the Mn-N-TiO2/Bentonite composite as a catalyst in degrading congo red in visible light and to determine the effect of irradiation time on the effectiveness of photodegradation of congo red catalyzed Mn-N-TiO2/Bentonite. The synthesis of the Mn-N-TiO2/Bentonite composite was carried out using the sol-gel method. Characterization was carried out with UV-Vis DRS, XRD, FTIR, and SEM-EDX. A photocatalytic activity test on Congo red degradation was carried out using ultraviolet and visible lamps. The results of the characterization of the Mn-N-TiO2/Bentonite configuration show that the band gap energy of Mn-N- TiO2/Bentonite with a variation of 5 g has a band gap energy of 2.14 eV with anatase crystal form. In the IR spectrum, there is a shift in wave number from 1634.49 to 1433.11cm-1, there is the vibration of the NO bond, absorption below 1000 cm-1 indicates the presence of Mn-O bonds, and absorption at wave number 1049.28 cm-1 indicates the presence of ions. manganese metal trapped in the TiO2 matrix. This spectrum indicated the presence of manganese and nitrogen. These results were confirmed by the EDX instrument, which showed the presence of 0.60% Mn and 0.04% N. SEM results show that particles that are still agglomerated and have a large size, which is influenced by water vapor in the TiO2 crystal structure. The results showed that the photodegradation activity increased significantly up to 40.9075% at 30 minutes of irradiation for the Mn-N- TiO2/Bentonite composite and 20.0225% under exposure to ultraviolet light.
Profil Morfologi dan Difraksi Arang Hasil Pirolisis Beberapa Jenis Kayu Lokal Provinsi Bengkulu, Indonesia: Morphology and Diffraction Study of Charcoal By-Products from the Pyrolysis of Several Local Woods from Bengkulu Province, Indonesia Nurwidiyani, Ria; Triawan, Deni Agus; Rahman, Arief Aulia; Yudha, Sal Prima
KOVALEN: Jurnal Riset Kimia Vol. 10 No. 3 (2024): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2024.v10.i3.17289

Abstract

Wood, as a basic material for the furniture industry, creates waste problems in the form of wood sawdust. Wood sawdust is a material that can be utilized by processing it through a pyrolysis process to produce liquid smoke and charcoal. Charcoal resulting from sawdust pyrolysis of Azadirachta excelsa, Durio zibhetinus, Swietenia mahagoni, and Coffea sp. wood has different characteristics. Pyrolysis was carried out at 300–350 °C for 6 hours. Characterization was carried out using SEM-EDS and XRD. Based on the research, it is known that the character of the charcoal resulting from pyrolysis using XRD shows that the charcoal composition of each wood has similar characteristics, as indicated by the presence of a broad peak at 2 theta 25° indicating that the charcoal formed has an amorphous structure. In comparison, the 2 theta peaks of 17° and 29° respectively, indicate the presence of lignin and CaCO₃ in charcoal. The morphological structure of the charcoal surface based on the results of SEM analysis shows a similarity in morphology between Swietenia mahagoni and Coffea sp. Wood charcoal with small pore diameters and distances apart, as well as between Durio zibhetinus and Azadirachta excelsa wood charcoal, which resembles a honeycomb structure. The composition of charcoal resulting from pyrolysis shows that the largest component of charcoal is carbon with a percentage of 45.4-56%, calcium with a percentage of 10-15.2%, and oxygen with a percentage of 22.5-38.4%, with minor components in the form of aluminum, boron, silicon, and potassium.
Efektivitas Limbah Puntung Rokok sebagai Inhibitor Korosi dalam Medium Asam Klorida pada Baja A36 dengan Metode Microwave Assisted Extraction: Effectiveness of Cigarette Butts Waste as Corrosion Inhibitor in Hydrochloric Acid Medium on A36 Steel by Microwave Assisted Extraction Method Alatif, Ikhsan Akmal; Permatasari, Rahma Puspa; -, Maya Futri Nur Rachmat; Wulandari, Dwi Arsya; Sonia, Gina; Aura, Azma Addina; Trirahayu, Dhyna Analyes; Hadiningrum, Kunlestiowati
KOVALEN: Jurnal Riset Kimia Vol. 10 No. 3 (2024): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2024.v10.i3.17395

Abstract

Cigarette butts are one of the wastes found in many places, and their presence can damage the environment. One way to reduce the amount of cigarette butts waste is to process them into corrosion inhibitors. This study aims to extract tobacco from cigarette butts using 96% ethanol solvent by varying the extraction time for 5, 10, 15, and 20 minutes, and microwave power of 150 watts and 300 watts, and calculating the efficiency of corrosion inhibitors in acidic environments. The extraction method used was Microwave Assisted Extraction (MAE). From the extraction process, it is known that the optimum extraction power of 150 watts in 15 minutes produces the highest yield of 64.52%. Based on phytochemical and GC-MS tests, it is known that cigarette butt extract contains antioxidant compounds in the form of alkaloids, pyranones, and terpenoids as corrosion inhibitor compounds. Based on corrosion testing, it is proven that the addition of cigarette butt waste extract corrosion inhibitors can suppress or reduce the corrosion rate that occurs on metals with the most excellent efficiency of 82.26% with an extract concentration of 2000 ppm. And the SEM-EDX test results concluded that the corrosion inhibitor from cigarette butts waste extract can withstand the formation of rust on the metal.
Klasifikasi dan Autentifikasi Tanaman Seurapoh (Chromolaena odorata Linn) Menggunakan Metode Kombinasi Spektroskopi Inframerah dan Kemometrik: Classification and Authentication of Seurapoh Plant (Chromolaena odorata Linn) Using a Combination of Infrared Spectroscopy and Chemometric Methods Karma, Taufiq Karma; Kala, Pasyamei Rembune; Shofi, Shofi; Zafirah, Zafirah
KOVALEN: Jurnal Riset Kimia Vol. 10 No. 3 (2024): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2024.v10.i3.17460

Abstract

This study classifies the Seurapoh plant (Chromolaena odorata Linn) collected from various locations across Aceh Province. The analysis aims to determine the influence of geographic differences on the origin of Seurapoh plants by performing classification and authentication. Seurapoh leaf samples in this study were obtained from several locations, including Aceh Besar, Sabang, Southwest Aceh, South Aceh, Aceh Jaya, Bireun, Bener Meriah, and Central Aceh. Classification of Seurapoh leaf extracts was carried out using Principal Component Analysis (PCA), while authentication was conducted using Linear Discriminant Analysis (LDA). The PCA score plot analysis results indicate that it can explain a total data variance of 62%. Based on the PCA score plot, samples generally form three distinct groups: Group 1 consists of samples from the highland region of Gayo, specifically Central Aceh (TA) and Bener Meriah (BM); Group 2 consists of samples from the coastal areas of Aceh, namely Southwest Aceh (ABD), South Aceh (AS), Aceh Jaya (AJ), and Bireun (Br); and Group 3 comprises samples from geothermal manifestation areas of Seulawah Agam and Jaboi. The classifications derived from PCA analysis were subsequently authenticated using LDA. The LDA analysis results indicate that the LDA model, based on cross-validation, accurately predicts the origin locations of Seurapoh leaf samples with a 100% accuracy rate.

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