Universitas Negeri Manado, Jurusan Kimia: Open Journal Systems
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Sintesis Selulosa Suksinat Melalui Reaksi Esterifikasi Asam Suksinat
Get PDFCellulose is a biopolymer that is widely applied in various fields. Modification of cellulose is needed to increase the added value of cellulose. One of these cellulose derivatives is cellulose succinate. This study aims to synthesize succinic cellulose using succinic acid. This research covers the synthesis of cellulose succinate via esterification reaction with a variation of succinic acid (1.6%; 2.4%; 3.2% and 4.0%), DS determination by titration method, and characterization with FTIR. Based on the synthesis results, the optimum DS was obtained at 2.4% succinic acid (SS3) concentration, namely 0.692. The results of the characterization with FTIR also showed the presence of a C=O absorption band indicating the presence of cellulose succinate monoester
Effectiveness of Natural Zeolite Mass Variation for Turmeric Solution Adsorption Process
Get PDFThe purpose of this study was to observe the effectiveness of adsorption process in turmeric solution with different zeolite masses. The method used was to highlight the solution with flashlight which was then measured using a lux meter. To support this research, we used a solution of turmeric with zeolite with mass variations ranging from and tested 3 times with a lux meter. The results obtained indicated that there are differences in the adsorption rate of turmeric solution with zeolite mass from 1 to 2,5 grams. This difference occurred because of the difference in the mass of the zeolite between which adsorbed the turmeric solution. The lux meter showed different results in each test and the water clarity level was different for each added mass variation. In addition, the compatibility of the experimental results with the isotherm adsorption model shows the adsorption mechanism that occurred. Thus, the difference in mass has an impact on use on a larger scale as needed. This research is expected to provide new knowledge for the community about the benefits of zeolite for water purification process in daily life
PEMBUATAN DAN KARAKTERISASI KARBON AKTIF DARI ARANG TEMPURUNG KELAPA DENGAN KOMBINASI AKTIVASI KIMIA DAN FISIKA
Get PDFKajian pembuatan karbon aktif dari tempurung kelapa telah dilakukan dengan perlakuan kimia dan fisika menggunakan aktivator HNO3 dan zat pengaktif gas CO2. Pembuatan karbon aktif dilakukan dengan pirolisis tempurung kelapa, kemudian diaktivasi secara kimia melalui proses perendaman dalam larutan HNO3 pada variasi konsentrasi 0,5; 1,0; 1,5; dan 2,0 M selama 12 jam. Karbon aktif dengan kualitas terbaik dihasilkan dari karbon aktif dengan konsentrasi HNO3 1,5 M pada temperatur 8000C . Hasil karakterisasi pada konsentrasi ini menghasilkan rendemen karbon aktif sebesar 73,41%%, kadar air 3,25%, kadar zat mudah menguap 19,20%, kadar abu 1,18%, karbon terikat 78,29% dan daya serap terhadap iodium sebesar 294,60 mg.g. Angka daya serap iodium ini memenuhi Standar Industri Indonesia no.0258-7
Aktivitas Antioksidan Ekstrak Etanol Batang, Daun Dan Akar Kopasanda (Chromolaena odorata L) dengan Metode ABTS (2,2’- azino - bis (3-etilbenzotiazolin -6- asam sulfonat)
Get PDFKopasanda (Chromolaena odorata L.) is a plant that contains flavonoid compounds that can act as antioxidants. This study aims to determine the antioxidant potential of the ethanol extract of the stems, leaves and roots of kopasanda by looking at the IC50 value. The stems, leaves and roots of Kopasanda were extracted by maceration using 70% ethanol as solvent. The results of the antioxidant activity test using the ABTS method (2.2'- azino - bis (3 - ethylbenzothiazoline - 6- sulfonic acid) showed a very strong antioxidant activity with an IC50 value of 11.5380 g/ml leaves, 31.161 g/ml stems and 36,860 roots. g/ml with positive control of quarcetin obtained IC50 value of 1.698 g/ml. Based on these results, it can be concluded that the stems, leaves and roots of the encounter have very strong antioxidant activity against ABTS free radicals (2,2'- azino - bis (3 - ethylbenzothiazoline). - 6- sulfonic acid)
Analisis Struktur Morfologi Dan Gugus Fungsi Serbuk Kopi Robusta Toraja
Get PDFCoffee is one of the most popular beverages in the world. The purpose of this research is to examine the morphological structure and composition of Toraja Robusta coffee. Scanning Electron Microscopy (SEM) was used to analyze the morphological structure and elemental analysis of Robusta coffee powder, as well as functional group analysis using Fourier transform infrared spectroscopy (FTIR). Microscopic examination reveals that the surface of Toraja Robusta coffee grounds is uneven. Furthermore, the elements Carbon, Oxygen, Nitrogen, Potassium, and Magnesium were discovered in Toraja Robusta coffee powder. Furthermore, functional group analysis results show that Toraja Robusta coffee powder has several functional groups at various wave numbers. This research advances our understanding of the morphological structure and composition of Toraja Robusta coffee powder, which can be used as a reference in coffee processing and marketing. Furthermore, the findings of this study can help improve the quality and selling value of Toraja Robusta coffee as a local Indonesian coffee product that is distinct and distinct from other types of coffee
Skrining Fitokimia Dan Uji Sun Protection Factor (SPF) Ekstrak Daun Sungkai (Peronema Canescens Jack) Secara In Vitro
Get PDFSungkai leaves have bioactive compounds in the form of triterpenoids, alkaloids, flavonoids, phenolics, steroids and saponins. This compound contains a chromophore group (conjugated single double bond) which is able to absorb ultraviolet light thereby reducing radiation to the skin. The higher the value, the better it is used as a sunscreen. The purpose of this study was to determine the results of the phytochemical test of the ethanol extract of Sungkai leaves (Peronema Canescens Jack) and the Sun Protection Factor (SPF) test of the ethanol extract of Sungkai leaves (Peronema Canescens Jack) in vitro. The SPF values ​​produced at concentrations of 100, 200, 300, 400, and 500 ppm in ethanol extraction were 7.51; 15.93; 27.40; 34.87; and 39.86. Sungkai Leaf Extract (Peronena Cenescens Jack) can be used as a sunscreen ingredient, at concentrations of 200 ppm, 300 ppm, 400 ppm it is included in the suntan category (moderate to ultra protection) and in this SPF test the concentration will affect the resulting SPF value
Aplikasi Metode Titrasi Iodometri Untuk Determinasi Kadar Vitamin C Pada Jambu (Myrtaceae Family
Get PDFVitamin merupakan senyawa penting di dalam makanan walaupun kandungan yang terdapat di dalam makanan tersebut sedikit, hal ini disebabkan vitamin memiliki peranan vital di dalam tubuh manusia. Vitamin dapat dikelompokan dalam 2 golongan yaitu vitamin yang larut di dalam lemak yaitu A, D, E, F dan K, sedangkan untuk vitamin yang larut dalam air diantaranya adalah vitamin C dan vitamin B. Vitamin C merupakan senyawa antioksidan sekunder yang bekerja dengan cara menangkap senyawa radikal bebas. Kandungan vitamin C mudah ditemukan di dalam sayur-sayuran dan buah-buahan. Salah satu buah-buahan yang mengandungi vitamin C adalah buah jambu (Myrtaceae family). Penelitian ini bertujuan untuk mengetahui dan menganalisis kadar vitamin C yang terkandung dalam beberapa jenis buah jambu (Myrtaceae family). Metode yang digunakan adalah metode titrasi iodometri. Jenis penelitian ini yaitu kuantitatif-kualitatif eksperimental laboratorium. Sampel yang digunakan dalam penelitian ini yaitu jambu biji merah (Psidium guajava L.), jambu kristal (Psidium guajava, L.), dan jambu air merah (Syzygium aqueum). Penelitian diawali pembuatan iodium 0,05 N, pembakuan iodium, kemudian pembuatan indikator amilum 3%. Selanjutnya penetapan kadar vitamin C pada sampel jambu menggunakan metode titrasi iodometri. Rata-rata kadar sampel jambu biji merah, jambu kristal, dan jambu air merah 2,42 mg/100 gram
Pengaruh Penambahan FAME Terhadap Parameter CCR (Condradson Carbon Residu) Dan Sulfur Content Pada Produk Biosolar
Get PDFThe increasing number of vehicles in Indonesia causes the need for energy to increase. This situation has an impact on the decreasing availability of fuel oil. Currently, the Government of Indonesia has stipulated in the Regulation of the Minister of Energy and Mineral Resources No. 12 of 2015 the use of FAME mixed fuel by 30% in diesel products (B30). But it does not rule out the possibility that Indonesia will increase the content of FAME. So this study aims to determine the effect of adding FAME to Biosolar products on CCR and Sulfur Content parameters. The methods used are CCR (condradson carbon residue) analysis using ASTM D-189 and Sulfur Content Analysis using ASTM D-4294. The results showed that the higher the FAME, the higher the residual carbon value and the results for B0, B30, B35, and B40 were 0.0257; 0.039; 0.063; 0.0787%. While the value of sulfur content is decreasing where the more FAME is added to biodiesel products, the sulfur content in these products decreases in B0, B30, B35, and B40, namely 0.181; 0.114; 0.104; 0.096%
Pengaruh Model Pembelajaran ICARE Terhadap Hasil Belajar Kimia Siswa Pada Materi Hidrokarbon Kelas XI MIA di SMA Negeri 1 Tombatu
Get PDFTujuan dari penelitian ini adalah untuk mengetahui perbedaan hasil belajar kimia siswa yang diberi perlakuan menggunakan model pembelajaran ICARE dengan siswa yang diajarkan dengan cara konvensional pada materi hidrokarbon kelas XI MIA di SMA Negeri 1 Tombatu serta efektvitas model pembelajaran ICARE dan pembelajaran konvesional. Jenis penelitian yang dilakukan Quasi Experimental Design yaitu pretest-posttest control group design, yang merupakan penelitian menggunakan dua kelompok, yang satunya kelompok eksperimen sedangkan yang lainnya kelompok kontrol. Populasi dalam penelitian ini yaitu seluruh kelas XI MIA SMA N 1 Tombatu dan sampel terdiri dari 2 kelas, yaitu kelas XI MIA 2 sebagai kelas eksperimen dan kelas XI MIA 1 sebagai kelas kontrol masing-masing berjumlah 18 orang. Berdasarkan data hasil penelitian diperoleh hasil analisis uji-t dengan sig (2-tailed) sebesar 0,001 < 0,05, artinya H0 ditolak dan H1 diterima. Melalui uji efektivitas (N-Gain) didapat 63% model pembelajaran ICARE masuk dalam kategori cukup efektif. Dengan demikian terdapat perbedaan Model Pembelajaran ICARE dengan pembelajaran konvensional pada Hasil Belajar Kimia Siswa materi Hidrokarbon kelas XI MIA di SMA Negeri 1 Tombatu serta model pembelajaran ICARE cukup efektif dalam pembelajaran kimia materi hidrokarbon dan pembelajaran konvensional tidak efektif
Mechanical And Microstructural Assessment Of Synthetic Aluminosilicate Based Geopolymer Dental Material
Get PDFOrthodontic treatment with fixed brackets was performed to transmit the pressure from the wire to the periodontal tissues to produce tooth movement. Ceramic material can be used not only to improve the aestheticness but also maintains good mechanical properties. This study aims to determine the mechanical properties and morphological of synthetic aluminosilicate based geopolymer for aesthetic orthodontic brackets applications made by synthesizing alumina (Al2O3), silica (SiO2), and magnesia (MgO) from sol-gel method. Geopolymer nanocomposite was made by activating synthetic precursor with alkali solutions consists of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) solution which has molarity variations of 8M (GP-8M) and 14M (GP-14M). The test results using an X-Ray Diffractometer (XRD) showed that the crystalline phase of (Mg,Si)Al2O4 spinel was successfully presented in the synthesized nanocomposite. The average hardness test results using the Vickers hardness tester for Geopolymer Nanocomposite with 8M and 14M alkali activator were 259.15 and 298.90 VHN, respectively. The results of the surface morphological characterization using Scanning Electron Microscope (SEM) of the samples showed the porosity of GP-14M was smaller than GP-8M, which explains the hardness test value difference. This shows Geopolymer is a potential material for orthodontic brackets manufacture