KOVALEN: Jurnal Riset Kimia
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Siklisasi Sitronelal Menggunakan Polimer Penyangga Katalis H2SO4 Berbahan Dasar Eugenol: Citronellal Cyclization Using Polymer Based-Eugenol Supported H2SO4 Catalyst
Get PDFResearch on citronellal cyclization using a polymer based on eugenol supported H2SO4 catalyst has been carried out. The study aim was to determine the ratio of the addition of polymer based-eugenol supported H2SO4 catalyst used to produce the highest isopulegol. Citronellal cyclization was carried out using variations of catalyst concentration (1, 2, 3, 4, and 5%) and reaction time (30, 60, and 90 minutes). The results have obtained a yield of 50.67% found in the catalyst concentration of 1% and 90 minutes reflux time. From the results of GC-MS analysis, 29 compounds were read and among them isopulegol which was read at retention time 19.703 at peak 9 and peak area 4.76%. And the isopulegol results obtained are 11.34%
Potential Combination of Kapok Leaf Extract (Ceiba pentandra G.) and Turmeric Extract (Curcuma domestica Va) as an Anticancer Compound
Get PDFCombination of kapok leaf extract (Ceiba pertandra G.) and turmeric extract (Curcuma domestica Va.) was carried out to determine the potential of extracts in treating cancer with BSLT and murine cells P388. Cancer is a disease that is very feared because it’s difficult to cure, and even rarely causes death. The sample was extracted with methanol, the extract was mixed so that the mixture extract from the two samples was obtained. The results showed that in the BSLT test the mixed extract had a bioactivity against shrimp larvae with an LC50 value of 142.946 ppm. While in Leukemia P388 cell testing showed that the combination of mixed extracts had a cytotoxic effect on Leukemia P388 cancer cells with inhibitory concentration values of 54.34 ppm. This shows that the kapok leaf extract (Ceiba pentandra G.) and combination of turmeric extract (Curcuma domestica Va.) has potential and can be developed as an anticancer agent because it has an IC50 value that can inhibit murine P388 cell growth and LC50 value which can kill shrimp larvae Artemia salina L
Analisis Termodinamika dan Kinetika Nanopartikel Karbon (C-Dot) dari Buah Durian Sebagai Inhibitor Korosi Tembaga: Thermodynamics and Kinetics Analysis of Carbon-Dots from Durian as Copper Corrosion Inhibitor
Get PDFCorrosion is a physical interaction between the metal and its environment, which results in changes in the metal's properties due to chemical or electrochemical reactions. The corrosion rate can be reduced by adding a corrosion inhibitor. Uses of nanotechnology for corrosion prevention is one of the first technical because almost made structures rely on the stability of a 1–2 nm thick passive film which provides stability to the underlying material. Herein we report the thermodynamic and kinetic analysis of carbon-dots from Durian as inhibitor copper corrosion. To test the anticorrosive performance and analyze thermodynamic properties in its role as a corrosion inhibitor on copper using potentiodynamic polarization. The thermodynamic-kinetic parameters of corrosion obtained values of ï„H‡ = 60.44 kJmol-1, ΔS‡ = -73.9 kJmol-1, and ΔG‡ = 82.83 kJmol-1, show that the attendance of C-dot as a corrosion inhibitor causes a non-spontaneous reaction rate to be proven by increasing spontaneity (ΔG‡). The value of activation energy samples was higher than the blank, indicates the presence of C-dot effective to reduce the rate of corrosion of the metal
Kajian Pustaka Karakterisasi Perekat Polivinil Asetat Berbasis Air dengan Variabel Surfaktan: Water Base Polyvinyl Acetate Characterization with Surfactant Variable – a Review
Get PDFPolyvinyl acetate (PVAc) is an applicative polymer used as an adhesive material for one to another. These polymers can be synthesized through an emulsion polymerization process. In the industrial world, the process of making adhesive still involves environmentally unfriendly organic compounds containing xylene, benzene, and toluene. Therefore, water-based adhesive was introduced as an alternative to the PVAc synthesis solution. The aim of this literature review is to identify the type of surfactants used and analyze the PVAc characterization. This literature study focuses on the characterization of water-based PVAc with non-ionic nonylphenol (NP) surfactants including: NP-06, NP-10, NP 10 + 30, NP-30 and NP-40. Another surfactant used in this literature study is anionic surfactant Sodium Lauryl Sulfate (SLS) in units of Critical Micelle Concentration (CMC) including 1 CMC, 3 CMC, 5 CMC, 10 CMC, and 15 CMC. The result is a similarity in phenomena between the two types of surfactants. There is an increase in viscosity and a decrease in the value of the particle size as the surfactant increasing concentration used. However, in terms of the particle size, there is an optimal value where the specific NP surfactant concentration produces specific particle size with grit and at the specific SLS surfactant concentration produces relatively similar particle size
Pengaruh Penambahan Abu Sekam Padi Terhadap Peningkatan Kualitas Minyak Mandar: The Effect of Rice Husk Ash Addition on The Increasing of Mandar Coconut Oil Quality
Get PDFMandar coconut oil is one of the coconut processed products, which has become superior product in West Sulawesi especially in Majene regency. Unfortunately, the Mandar coconut oil can’t be used more than a month because the water content and free fatty acid content of the oil have exceeded the maximum standard of SNI, so it can adversely affect on health. On the other hand, the existence of rice husk in Indonesia itself especially in West Sulawesi has not received attention and is limited to a few needs such as for ash or livestock feed, and the rest is thrown away. This research aims to determine the effect of rice husk ash addition on the increasing of Mandar coconut oil quality. Completely randomized design was used in this research with 6 rice husk ash concentration variation levels i.e. 0%, 5%, 10%, 15%, 20% and 25%. The result shows that the addition of rice husk ash with 10% to 25% can reduce the water content of the oil until the quality standard of SNI is full filled. The highest reduction of water content was reached with 25% of rice husk ash concentration with 81% of reduction percentage. While, the addition of rice husk ash with 15% concentration can reduce the free fatty acid content of Mandar coconut oil until 32%
Elektroplating Grafena-Polianilina pada Stainless Steel sebagai Elektroda pada Elektrolisis Air untuk Produksi Hidrogen: Electroplating of Graphene-Polyaniline on Stainless Steel as Electrodes on Water Electrolysis for Hydrogen Production
Get PDFHydrogen production by water electrolysis can be optimalized by improve the working electrode. Stainless steel as working electrode was coated with graphene and polyaniline by using cyclic voltammetry method with Ag/AgCl as reference electrode and Pt as counter electrode. Coated electrodes were characterized by SEM-EDS and cyclic voltammetry method. Furthermore, the synthesized electrode was applied for water electrolysis by adding 1- 5 g/L NaHCO3. The characterization data showed that Stainless steel/Graphene-Polyaniline electrode can be synthesized by using cyclic voltammetry. The coating process was conducted at sweeping rate 10 mV/s on voltage -0.2 to 0.8 V for 10 cycles. The voltammograms showed that the highest cathodic peak current of electrolysis obtained at 0.491 mA by addition 2 g NaHCO3 on SS/G-PANi0,5 electrode, and the highest anodic peak current obtained at 0.191 mA by addition 2 g NaHCO3 on SS/G-PANi0,5 electrode. Based on the overpotential data, the smallest average potential difference of H+ adsorption obtained by SS/G-PANi1,0 electrode, and the smallest average potential difference of H+ desorption obtained by SS/G-PANi0,5 electrode.
Keywords: Stainless steel, hydrogen production, electroplating, electrocatalyst, electrolysi
Pemanfaatan Selulosa dari Rumput Gajah (Pennisetum purpureum) pada Sintesis Karboksimetil Selulosa (CMC) : [Utilization of Cellulose from Pennisetum purpureum at The Synthesis of Carboxy Methyl Cellulose (CMC)
Get PDFCellulose from Pennisetum purpureum has been used as the main ingredient in the synthesis of carboxymethyl cellulose (CMC). The purpose of CMC synthesis from the cellulose of Pennisetum purpureum is to obtain CMC compounds with the best degree of substitution (DS) value and the highest yield. The study was conducted using a completely randomized design with a factorial pattern consisting of two independent variables, namely the concentration of trichloroacetic acid (10%, 20%, and 30%) and reaction time (3 and 4 hours). The results showed that the CMC with the highest DS value (0.839) was obtained using 20% trichloroacetic acid with a reaction time of 3 hours. The highest CMC yield was 30.15% which was obtained using 30% trichloroacetic acid with a reaction time of 4 hours.
Keywords: Pennisetum purpureum, carboxymethyl cellulose, substitution degree
Pengaruh Asam Itakonat terhadap Properti Polimer Perekat Akrilik Berbasis Air: Effect of Itaconic Acid on the Properties of Acrylic Water Base Adhesive Polymer
Get PDFAcrylic-based polymer adhesive is a type of adhesive that can be used for pressure sensitive adhesive (PSA). Itaconic acid (IA) is a type of acid with 2 (two) OH groups which can form hydrogen bonds. The acrylic base can be used purely from its class. In some cases, however, the acrylic base can be used together with another base. Therefore acrylic-based adhesive with variable addition of itaconic acid was introduced in this study. In this application, the holding power property is one of the important parameters of a PSA. Therefore, holding power is the main parameter in this study. This research includes the preparation of tools and materials, mixing the main raw materials of acrylic monomer and itaconic acid with the types of surfactants and water, and product characterization. The polymerization process is carried out at a pressure of 1 atm with a temperature of 75°C - 80°C accompanied by stirring with a rotation rate of ± 500 rpm. The characterization of this research resulted in a PSA product with a holding power of 2 kg for 30 seconds to 620 minutes. While the resulting peel strength is 1.12 kgf / inc to 0.76 kgf / inc.
Keywords: itaconic acid, acrylic PSA, holding powe
Penyarian Konstituen Organik Daging Buah Gaharu (Aquilaria malaccensis Lamk.) dengan Metode Maserasi Berbantu Microwave dan Uji Aktivitas Sebagai Antioksidan: Organic Constituent Extraction of Gaharu Fruit (Aquilaria malaccensis Lamk.) Using Microwave Assisted Maseration Method and Activity Test as Antioxidant
Get PDFThis study was conducted to determine the organic constituents and to test the antioxidant activity and toxicity of gaharu fruit pulp extract (Aquilaria malaccensis Lamk.). Gaharu fruit pulp extract was obtained through Microwave Assisted Extraction (MAE) method and then extracted with a solvent with different polarity, namely ethyl acetate and n-hexane. The obtained yield of ethyl acetate extract of the gaharu fruit pulp was 40.827% w/v, whereas 0% w/v in n-hexane extract, therefore, no further test for n-hexane extract, so that the n-hexane extract was not tested for the next stage. The results of the organic constituents of the ethyl acetate extract of gaharu fruit pulp showed flavonoids, saponins, glycosides, phenols and tannins. Antioxidant activity testing was carried out using the DPPH method with vitamin C as a positive control. The results of the antioxidant activity test showed that IC50 of ethyl acetate extract of gaharu fruit pulp and vitamin C were 143.789ppm and 13.797ppm, respectively. Extracts from microwave-assisted maceration that were partitioned with ethyl acetate solvent were categorized into moderate antioxidants because the IC50 value was between 101-150ppm, while vitamin C was categorized as a strong antioxidant because the IC50 value was between 0-100ppm. Toxicity testing was also carried out on ethyl acetate extract of gaharu fruit pulp using the BSLT method. The results of the toxicity test of the ethyl acetate extract of gaharu fruit pulp showed activity with an LC50 value of 11.282ppm. Based on this research, the ethyl acetate extract of gaharu fruit pulp is considered to have an anticancer potential
Limbah Sabut Kelapa Muda (Cocos nucifera L.) sebagai Sumber Pewarna Kain: Young Coconut Coir (Cocos nucifera L.) Waste as a Source of Cloth Dye
Get PDFYoung coconut coir (Cocos nucifera Linn.) waste has the potential to be processed into a useful product, namely as a source of natural dyes, especially in cotton fabrics. Processing is carried out through a maceration process for 72 hours using 96% ethanol as solvent. The obtained extract was applied on cotton cloth with various concentrations of the extract solution, 5, 10, 15, 20, and 25%, and various soaking times of the fabric in the extract for 60, 90, 120, 150, and 180 minutes. The extract was analyzed using Uv-Vis Spekctrofotometer it showed that the ethanol extract or dye that is absorbed into the cotton fabric with various concentrations is 3.43, 4.82, 6.61, 7.79, and 9.03%, respectively. The various soaking times show that on the other hand that the extract absorbed into the fabric was successfully obtained around 7.75, 9.64, 10.81, 11.65, and 12.04%. The results show that the concentration of the extract solution and the increasing length of soaking time can increase the percentage of extract or dye absorbed in cotton fabric