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INDONESIA
Indonesian Journal of Chemical Science
Published by Universitas Negeri Semarang
ISSN : 22526951     EISSN : -     DOI : -
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry
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Articles 830 Documents
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The Utilization of Medical Mask Waste as a High-Quality Nanofiber Material a Review Victory, Shelly; Putri, Restani Eka; Sakhila, Shania; Hutagalung, Soluna Desbait; Amelia, Addela; Fabiani, Verry Andre
Indonesian Journal of Chemical Science Vol 10 No 2 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i2.49538

Abstract

Medical mask waste is part of the covid waste that can threaten the living creatures and environment since it was pathogenic and indestructible. Moreover, the waste management of medical mask waste is still ineffective due to the limit of technology and resource. The purpose of this review is to learn the potency of medical mask waste as the main component of nanofiber fabrication. This review is using the literature review method. There are some fundamental stages for creating nanofiber from polypropylene of medical mask waste, such as pre-treatment, making polypropylene solution, fabrication, and characterization. Removal of medical mask waste contaminants can be using a chemical solvent, dry heat, or exposure to ultraviolet C. Type of solvent plays a principal role in producing polypropylene solvent that is ready to fabricate. On the industrial scale, electrospinning is a commonly used method for nanofiber fabrication. The characterization of the fiber and pore size can be analyzed with scanning electron microscope (SEM) analysis, material crystallinity using x-ray diffraction (XRD) spectroscopy, and thermogravimetric analysis (TGA) measuring the thermal stability of nanofiber.
Characterization of Bioplastic Compostable PLA-Cellulose Based as Eco-friendly Packaging Karim, Wouda Fiorendita; Harahap, Muslim Arfanshah; Prakoso, Mochamad Galih; Finaldin, Muhammad Alhas; Kemala, Tetty
Indonesian Journal of Chemical Science Vol 10 No 3 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i3.49654

Abstract

Bioplastics have the potential a substitute for conventional plastics. Bioplastics can be made from PLA and cellulose formulated with organic fertilizer granules which have the potential to be environmentally friendly bioplastics because they are easily degraded in the environment. This study aims to determine the effect of adding granulated organic fertilizer (POG) to compostable bioplastics and to analyze its potential as environmentally friendly packaging. Bioplastics are made from PLA granules and cellulose with the same ratio of 95%: 5% and POG with a variation of 0.00 g; 0.50 g; 1.00 g; 1.50 g; and 2.00 g in 5.00 g (PLA-cellulose). The resulting bioplastics were investigated for their properties, including water vapor transmission rate, density, water absorption, and mechanical properties. The results showed that the addition of granule organic fertilizer (POG) had an effect on the rate of water vapor transmission, density, and mechanical properties of bioplastics and also provided good quality as environmentally friendly packaging. The elongation of bioplastic with the addition of 2 g of POG has a value of 11.86% water vapor transmission rate while the density of the addition of POG shows no significant difference.
Modification of Magnesium Oxide from Bittern Waste with Strontium Oxide for Palm Oil Transesterification Process Qoyyima, Diana; Jumaeri, Jumaeri
Indonesian Journal of Chemical Science Vol 10 No 2 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i2.50033

Abstract

Bittern has a high magnesium content, so that it can be used as a catalyst in the production of biodiesel through the transesterification process. MgO catalyst has a relatively low basicity, so it is necessary to add metal oxides such as SrO. This study aims to determine the characteristics and catalytic effectiveness of the SrO/MgO catalyst in the transesterification process of palm oil using GC and GCMS tests. Modification of SrO on the MgO catalyst was carried out using the impregnation method with a ratio of 1:3. The presence of SrO diffraction peaks on XRD analysis showed that SrO agglomerated on the MgO surface, this can be attributed to the morphology of the spheres which are homogeneously agglomerated. The result of basicity analysis shows that the addition of SrO can increase the number of moles of base of MgO. In the palm oil transesterification process using an SrO/MgO catalyst, the methyl ester conversion increased by 47.17% at the optimal reaction time of 2 hours, while the MgO catalyst only resulted in a conversion of 2.35%. Based on the results of the study, it was found that the addition of SrO could increase the catalytic effectiveness of MgO.
Method Validation on Functional Groups Analysis of Geopolymer with Polyvinyl Chloride (PVC) as Additive Using Fourier Transform Infrared (FT-IR) Sulistyani, Martin; Kusumastuti, Ella; Huda, Nuril; Mukhayani, Feri
Indonesian Journal of Chemical Science Vol 10 No 3 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i3.50419

Abstract

Fourier transform infrared (FT-IR) transmission spectroscopy is a method of analyzing functional groups on a compound that is simple, economical, and non-destructive. Geopolymers with PVC synthetic fiber additives are considered to have complete functional groups representing organic and inorganic compounds. The purpose of this study was to validate the functional group analysis method on geopolymers using FT-IR. To analyze the typical peaks of the spectra of the geopolymer compound, KBr pellets were prepared with 7 sample variations (0.25 mg; 0.50 mg; 0.75 mg; 1.00 mg; 1.25 mg; 1.50 mg; and 1. ,75 mg) on ​​the addition of KBr up to 16 mg interday and intraday for 3 consecutive days. The FT-IR spectroscopy method was validated with the parameters of linearity, detection limit (LoD), quantization limit (LoQ), accuracy, and precision. The analytical method applied is linear with the measured sample concentration range. The absorbance at wave number 986 cm-1 as the Si-O-Si absorption peak was chosen for method validation. From the results of the analysis, the regression coefficient (R2) is 0.9938 for geopolymers and 0.9923 for geopolymers with PVC as an additive. The analytical method that has been carried out shows that FT-IR spectroscopy is precise and accurate for measuring the spectrum of geopolymers and geopolymers with PVC additives.
Porcine Detection on Anti-Covid 19 Immunity Gelatin Capsules Sold at Market X in North Surabaya Using Quartz Crystal Microbalance (QCM) Sensors Syukrianto, Syukrianto; Umarudin, Umarudin; Madurani, Kartika Anoraga; Kurniawan, Fredy
Indonesian Journal of Chemical Science Vol 10 No 3 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i3.50456

Abstract

Immune gelatin capsules, which have not been fully indicated on the packaging, need to be investigated porcine or bovine using a Quartz crystal microbalance (QCM) tool. The advantages of the QCM tool are sensitivity to the crystal oscillation frequency at a specific temperature, humidity, pressure, speed, and vibration, which will make this piezoelectric oscillator used as a sensor with a high accuracy level. The purpose of this study was to determine the content of porcine (pork) or bovine (beef) in anticovi19 immunity gelatin capsules sold at market X, North Surabaya. The method used to distinguish pork gelatin and beef gelatin is a Quartz crystal microbalance (QCM) tool. In this study, the detection of anti-covid19 immunity gelatin capsules was carried out using a QCM tool. This research method was carried out in a factual experimental manner, and sampling with the quota technique was 3 grams for each sample with a different brand. The results of research conducted on four samples with other brands originating from the market X area of North Surabaya showed the detection results of 2 samples with adverse effects (-), and two samples with positive results (-), meaning that the negative samples contained beef gelatin (bovine) and the positive sample contains pork (porcine). A decrease in frequency characterized the sample of immunity gelatin capsules containing bovine gelatin. In contrast, the sample of immunity gelatin capsules containing porcine gelatin was characterized by increased frequency.
Analysis of the Load and Status of Organic Matter Pollution in Beringin River Semarang Afwa, Rainuy Saninzita; Muskananfola, Max Rudolf; Rahman, Arif; Suryanti, Suryanti; Sabdaningsih, Aninditia
Indonesian Journal of Chemical Science Vol 10 No 3 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i3.50705

Abstract

Beringin river is a river located in Tambakaji Village, Ngaliyan District, Semarang City. This river flows from Mijen District and Ngaliyan District and empties into Tugu District. Disposal of domestic waste and industrial waste in Beringin River it can cause a decrease in water quality such as increasing concentrations of Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) which can affect organic matter to be high. The purpose of this study was to analyze the BOD and COD pollution loads and to assess the pollution status of the Beringin River, Semarang using the Pollution Index method based on the Decree of the Minister of Environment Number 115 of 2003. Sampling was carried out two times with an interval of 2 weeks on March 16, 2021 and March 30, 2021. The material used in this research is water samples taken from three stations determined using the purposive sampling method based on regional characteristics. Water quality variables analyzed were temperature, discharge, pH, DO, BOD and COD. The results of the water quality research show that BOD and COD variables do not meet the quality standards. The calculation of the pollution load of the BOD and COD variables in the first sampling obtained an average result of 2.176.97 kg/day and 7,022.82 kg/day, while in sampling two each obtained an average result of 6,306.69 kg /day and 20,345.39 kg/day. The results of the Pollution Index (IP) on the Beringin River ranged from 4.82 to 4.84 classified as mildly polluted.
Preparation of PVA/ME/β-CD and PVA/ME Nanofibers by Electrospinning and Their Activity as a Drosophila melanogaster Attractant Islamiyah, Anisalia Nur; Cahyono, Edy
Indonesian Journal of Chemical Science Vol 10 No 3 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i3.51118

Abstract

Nanofibers are fibers with diameters in the nanometer range. In this study, PVA/ME and PVA/ME/β-CD nanofibers membrane are made by electrospinning method to determine the effect of matrix composition on the characteristics of the nanofibers and their activity as a Drosophila melanogaster attractant. PVA, Methyl Eugenol 98%, and β-Cyclodextrin were used for the electrospinning process. To get the best fibers morphology, the concentration of the sample was varied β-cyclodextrin (β-CD) (30% and 61%), methyl eugenol (5%, 10%, and 12%). The PVA concentration was prepared (was kept) at 12%. The ratio of β-CD and methyl eugenol was set at 1:1; 1:2; and 2:1. The electrospinning parameters were adjusted as 15 kV applied voltage, 10 cm tip-to-collector distance, and 0.5 mm inner diameter of the metallic needle. The average diameter of nanofibers PVA is 92 ± 890 nm. The average diameter of nanofibers PVA/ME is 95±10 nm. The average diameter of nanofibers PVA/ME/β-CD is 100 ± 150 nm. The result of IR spectra shows that PVA and β-CD matrix can trap methyl eugenol compounds as seen from the groups of C=C, –OCH3, and –CH=CH2. Attractant test showed that nanofiber PVA/ME/β-CD is the best product of nanofiber because it has the smallest number of beads and has the maximum activity that can trap the fruit flies with a total amount of 71 flies in a week
Acivated Activated Carbon from Kepok Banana Peel (Musa padisiaca L.) as Methyl Orange and Methyl Violet Adsorbent in Aqueous Solution Anindya, Bella Diska; Mahatmanti, F. Widhi; Kusumastuti, Ella; Wahyuni, Sri
Indonesian Journal of Chemical Science Vol 10 No 3 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i3.51178

Abstract

Kepok banana peel is used as raw material for activated carbon for adsorption of methyl orange and methyl violet because it has a high lignocellulose content of 90.7%. Methyl orange and methyl violet are azo dyes that have a benzene structure that is very difficult to degrade. This study aims to determine the characteristics of activated carbon from kepok banana peel waste and to determine the optimum conditions for adsorption of methyl orange and methyl by activated carbon which include pH, contact time, and initial concentration of dye. This study includes the preparation of adsorbents (activated carbon from banana peels activated ZnCl2) and adsorption optimization includes optimization of pH, contact time, and concentrations of methyl orange and methyl violet in solution. The results showed that the characterization of activated carbon using an infrared spectrophotometer contained the presence of O-H, C=O, C-H, and C-O groups on activated carbon without activation, activated ZnCl2, and after adsorption was used. Characterization using a surface area analyzer with the BET method showed that activated carbon without activation had a surface area of ​​2.278 m2/g and a pore diameter of 2.0548 nm which was included in the mesoporous category. While activated carbon activated ZnCl2 has a surface area of ​​106.287 m2/g and a pore diameter of 1.5111 nm which is included in the category of micropores. The optimum conditions for methyl orange adsorption were obtained at pH 3, a contact time of 80 minutes, and a concentration of 0.3 mmol/L, while the optimum conditions for methyl violet adsorption were obtained at pH 5, a contact time of 80 minutes, and a concentration of 0.4 mmol/L.
The Synthesis of TiO2/PDMS Composites as Antibacterial Coatings on Cotton Fabrics Priyadi, Rizki Feby Gardika; Wahyuni, Sri
Indonesian Journal of Chemical Science Vol 10 No 3 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i3.51297

Abstract

Antibacterial properties on a substrate surface can occur due to two mechanisms, photocatalytic mechanism and the hydrophobic mechanism. Titanium dioksida (TiO2) is a material that has photocatalytic properties and polydimethylsiloxane (PDMS) is a material that is hydrophobic. TiO2 can be modified with PDMS to produce antibacterial materials. This modification can be done by compositing TiO2 and PDMS. The aim of the study was to determine the effect of TiO2/PDMS composites on the antibacterial properties of the coated cotton fabric on the surface. TiO2/PDMS composites were synthesized using the sonication method. The results of XRD analysis of TiO2 showed that TiO2 was crystalline with an anatase phase and had an average crystal size of 31.24 nm. The results of the FTIR analysis showed that Si–O–Ti vibrations appeared at a wave number of 874.53 cm-1 which indicated the formation of bonds between TiO2 and PDMS. TiO2/PDMS composites were coated on the surface of cotton fabrics by the dip-coating method. The results of the hydrophobic test showed that the largest contact angle was produced by the TiO2/PDMS composites coated fabric with a ratio of 1:2. The hydrophobic nature contributes to not getting wet easily on cotton fabrics, thereby reducing moisture which can prevent the growth of bacteria on the fabric. The results of the antibacterial test showed that the composites had an inhibitory effect on S. aureus bacteria. The UV irradiated TiO2/PDMS composite provided a larger diameter of inhibition zone. The diameter of the largest inhibition zone in the TiO2/PDMS composite coated fabric with a ratio of 2:1.
Effect of Hidoxyl Substitution on Cobalt Phthalocyanine as Catalyst for Oxygen Reduction Reaction Using DFT Method Wulandari, Hepi; Kasmui, Kasmui
Indonesian Journal of Chemical Science Vol 10 No 3 (2021)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v10i3.51605

Abstract

Oxygen Reduction Reaction (ORR) is an important reaction in the cathode and the main limiting factor of performance for fuel cells. The process of dioxygen (O2) reduction is not easy, due to its electronic configuration and high activation energy barrier, thus ORR needs to be catalyzed. Today there have been many developed catalysts such as phthalocyanine metal. CoPc compounds modified with hydrogen atoms are substituted by the OH group into CoPc(OH)16 to increase the activity of catalysts and the stability of the molecular structure of these catalysts in ORR applications. The purpose of the study was to explain the ORR reaction path in CoPc(OH)16 molecule, calculate DFT calculations using Material Studio software with DMol3 modules, PBE and PW91 exchange-correlation functions, and DNP basis set to determine structure optimization, with adsorption energy of O2, H2O, OH, H2O2, and H2O molecules on the surface of CoPc(OH)16 molecules. The results of CoPc(OH)16 optimization cause an increase in electron affinity values, decrease chemical hardness values, increase molecular reactivity and also increase binding energy between atoms. While adsorption results by CoPc(OH)16 amplify O2 adsorption energy and H2O2 adsorption energy, weakening OH adsorption energy. Through optimization results during the adsorption process also proves the CoPc(OH)16 catalyst through the two-electron reduction pathway in the ORR process. Calculations using the PW91 function produce lower adsorption energy than the PBE function, so the calculation using the PW91 function is better.

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