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ALCHEMY Jurnal Penelitian Kimia
Published by Universitas Sebelas Maret
ISSN : 14124092     EISSN : 24434183     DOI : -
Core Subject : Science, Social, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry Energy Environmental Science Materials Science & Nanotechnology
ALCHEMY Jurnal Penelitian Kimia is a chemistry journal published by Sebelas Maret University, Surakarta. ALCHEMY Jurnal Penelitian Kimia publishes original research articles or review articles in organic chemistry, inorganic chemistry, analytical chemistry, physical chemistry, biochemistry, and environmental chemistry.
Arjuna Subject : -
Articles 264 Documents
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REPLACING SODA ASH (NaOH) WITH KALIUM HYDROXYDE (KOH) IN DESTILATION OF BINARY ETHANOL-WATER MIXTURE Ana Ulfa Istiqomah; Fitria Rahmawati; Khoirina Dwi Nugrahaningtyas
ALCHEMY Jurnal Penelitian Kimia Vol 12, No 2 (2016): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.12.2.1876.179-189

Abstract

Soda ash (NaOH) has been used in bioethanol production in the second step destillation to increase the purity up to 90%. The destillation process will produce waste water with a high sodium content. The soda ash itself serve as an electrolyte to modify the colligative properties of the water-ethanol mixture allowing the disappearance of azeotropic point. This research aims to study the replacement of NaOH with KOH, in which the kalium is a nutrient to maintain soil fertility. This research study the thermodynamics properties, vapor-liquid equilibrium, colligative properties and also its azeotropic point in the destillation of water-ethanol mixture when KOH and NaOH were used as the additive. A model of water-ethanol mixture at a various composition of 0-100 weight % of ethanol was used. The electrolyte addition was 0.1 mol electrolyte/total weight of ethanol-water. The result shows that the addition of electrolyte into ethanol-water mixture eliminate the azeotropic point and allows the ethanol molecules to separate from water. The enthalpy of mixing between water-ethanol is 239.601 kJ/mol. It becomes 259.796 kJ/mol and 264.793 kJ/mol after the addition of NaOH and KOH, respectively. It confirming the endothermic mixing process due to different polarity between water and ethanol. The presence of electrolyte even reduce more their molecular interaction. However, the change to irregularity result a high positive entropy values that result the negative Gibbs free energy. It confirms the spontaneity of mixing. The vaporization enthalpy, Hvap, of water-ethanol mixture is 76.229 kJ/mol and it becomes 235.366 kJ/mol and 126.189 kJ/mol after the addition of NaOH and KOH. It indicates that the presence of electrolyte inhibites vaporization of water as the major component and allowing ethanol molecules to vapor producing more high purity ethanol.
SEPARATION OF CHROM (VI) FROM ELECTROPLATING WASTE USING POLYMER INCLUSION MEMBRANE (PIM) METHOD Muhammad Cholid Djunaidi; Khabibi Khabibi; Rizka Nurfitriana
ALCHEMY Jurnal Penelitian Kimia Vol 13, No 1 (2017): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.13.1.4562.119-132

Abstract

Research of chromium (VI) separation has been done using polymer inclusion membrane (PIM) method. This study aims to generate PIM, separate the metal ion chromium (VI) using PIM and determine the effect of the concentration of the feed phase, the thickness of the membrane and the amount of usage of the membrane for ion chromium (VI) diffusion.Polymer inclusion membrane (PIM) was made by mixing Aliquat 336-TBP as carrier compounds, PVC as the base polymer, DBE as a plasticizer and THF as a solvent. PIM membrane was placed between the source of analyte as a feed phase and result of the separation as a receiver phase. Feed phase was electroplating waste metal containing chromium (VI) at pH 4, while the receiver phase was a 2 N NaCl solution with a pH 6.7. The change of variables in this study were the concentration of the feed phase at various dilution i.e., 100x, 50x and 10x, the thickness of the membrane i.e., 25 μm, 20 μm and 10 μm, and the time of membrane using i.e., 1, 2 and 3 times. The concentration of chromium (VI) diffused after separation process was analyzed by atomic absorption spectroscopy (AAS). The stability of membrane was observed by analyzing the presence of membrane’s component in the feed phase and in the receiver phase. The analysis was conducted by UV-Vis spectrophotometry. Meanwhile, scanning electron microscopy (SEM) analysis was used to determine the morphology of membrane surface.The results showed that the chromium ion concentration diffused from the feed phase was 99.24%, meanwhile the 85.88% of it diffused to the receiving phase. The highest Cr(VI) ions diffusion was occured at the first use of PIM membrane with a thickness of 10 μm and the concentration of the feed phase was 10.55 ppm (resulted from 100 times dilution). Therefore, it can be concluded that the diffusion of chromium (VI) ion was influenced by the concentration of feed phase, the thickness of membrane and the number of membrane application.
HDO Reaction of THF Using Pt/γ-Al2O3 Catalyst Enriched by Alumina: Effect of Temperature to Product Distribution, Rate of Reaction and Deactivation of Catalyst Hidayat, Yuniawan; Nurcahyo, Idul Fitri; Sofiana, Ana; Saputro, Arifin Dwi
ALCHEMY Jurnal Penelitian Kimia Vol 10, No 1 (2014): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.10.1.5.94-104

Abstract

Effect of temperature variation to product distribution, rate and deactivation of catalyst of tetrahydrifuran hydrodeoxygenation have been conducted using Pt/gAl2O3 with aluminum enrichmen. Reaction was conducted by flow system. Product of reaction were analyzed as propane (C3) and buthene derivate (C4). At 350ºC, reaction product and rate constant were optimum. At higher temperature, product distribution was shift from C4 to C3. Lowering pore size catalyst, surface area and acidity of catalyst were responsible to catalyst deactivation. Deactivation process was follow exponential regression.
Study Pore Characterization of γ-Alumina – Activated Carbon Composite Made of Cassava Peels (Manihot esculenta Cranz) Hartini Hartini; Yuniawan Hidayat; Mudjijono Mudjijono
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 1 (2015): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.1.106.47-57

Abstract

A composite of γ-alumina and activated carbon made of cassava peels was studied in terms of its pore structures and its properties. The objective of this study was to determine the interaction and structure, as well as the character and pore size of γ-alumina – activated carbon composite.Carbon made of cassava peels was activated by H2SO4 and its activities were tested according to the Indonesian Industrial Standards (SII). The addition of activated carbon into γ-alumina made in variations of 10, 20, 30, 40 and 50 % w/w, of the total weight of 10 grams. The composite of γ-alumina - activated carbon was characterized by FTIR, SAA (Surface Area Analyzer), XRD, and determination of Hysteresis Loop composites.The greater addition of activated carbon to γ-alumina causes intermolecular interactions between –O-H groups form rehydrated hydrogen bonds in the composite is greater. The structure of γ-alumina in the composites remain intact although the percentage of activated carbon in composite is large. The total pore volume and surface area using the BET method of the composite decreases with increasing activated carbon percentage. The greater addition of activated carbon to γ-alumina causes size of mesoporous composites decreased with the characteristic of a composite formed is closer to the activated carbon.
Substitution Reaction of Hydroxy of Citronellol with Chloride Using A Mixture of Ammonium Chloride and Sulphuric Acid Endah Sayekti; Imelda H Silalahi; Titin Anita Zaharah
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 2 (2015): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.2.720.135-146

Abstract

Substitution reaction of hydroxy of citronellol with chloride using a mixture of ammonium chloride (NH4Cl) and sulphuric acid (H2SO4) has been conducted. The citronellol was obtained from the reduction of citronellal using sodium borohydride (NaBH4) at room temperature for 30 minutes. Substitution of hydroxy of citronellol with chloride ion was carried out at 80 oC and molarity ratio of citronellol and NH4Cl 1:1, 1:2; 1:3; and 1:4 respectively. Identification of the product by gas chromatography-mass spectrometry (GC-MS) showed that the substitution reaction produced 2-isopropyl-5-methyl-1-chlorocyclohexane compound with rendemen 64,49 % in mol ratio of 1:4. The infra red (IR) analysis showed that there was a vibration at wave number 763 cm-1 which is a typical C-Cl vibrations.
Antibacterial Activity of Germacrone Sesquiterpene from Curcuma Xanthorrhiza Rhizomes Hartiwi Diastuti; Yana Maolana Syah; Lia Dewi Juliawaty; Marlia Singgih
ALCHEMY Jurnal Penelitian Kimia Vol 12, No 2 (2016): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.12.2.1726.103-111

Abstract

The aim of this research was to isolate and indentify the terpenoid compound from Curcuma xanthorrhiza rhizomes and its antibacterial activity. Isolation was carried out by using vacuum liquid chromatography and centrifugal chromatography. The structure was determined by NMR spectroscopy (1H-NMR, 13C-NMR 1D and 2D), then compare with data from literatures. Antibacterial test was carried out by using  microdillution methods and evaluated against eight bacteria. They are Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Enterobacter aerogenes, Pseudomonas aeruginosa, Salmonella typhi, Shigella dysentriae and Vibrio cholerae. The result showed that the isolate was a white crystal which was indetified as germacron-type sesquiterpene. Germacron have highest activity againts P. aeruginosa, MIC 15.6 µg/mL and MBC 31.2 µg/mL.
SYNTHESIS AND CHARACTERIZATION OF Fe2O3 NANOPARTICLES USING Averrhoa bilimbi AS BIOMATERIAL CHELATING AGENT FOR NANOFLUIDS APPLICATION Arie Hardian; Alvi Aristia Ramadhiany; Dani Gustaman Syarif; Senadi Budiman
ALCHEMY Jurnal Penelitian Kimia Vol 13, No 2 (2017): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.13.2.4348.133-146

Abstract

The aim of this work was to determine the effect of calcination temperature on the characteristics of Fe2O3 nanoparticles (NPs) in sol-gel synthesis. The obtained Fe2O3 NPs was then used as material for preparation of Fe2O3-water nanofluids. Nanofluids is a mixture between basic fluid like water and 1 - 100 nm solid particles (nanoparticles). Nanoparticles of Fe2O3 have been synthesized from the local mineral Jarosite using sol-gel method by using starfruit (Averrhoa bilimbi) extracts as the chelating agent. The calcination temperature was then varied from 500 ºC to 700 ºC for 5 hours. Based on the X-Ray Diffraction (XRD) analysis, the diffraction pattern of obtained Fe2O3 was relevant with the JCPDS data No. 33-0664 for α-Fe2O3 with hexagonal crystallite system. The crystallite size (Scherrer’s Equation) of obtained α-Fe2O3 nanoparticles at calcination temperatures of 500 ºC, 600 ºC and 700 ºC was 50 nm, 48 nm and 40 nm, respectively. The Surface Area of Fe2O3 NPs at temperature of 500 ºC, 600 ºC and 700 ºC was 45.45 m2/g; 26.91 m2/g and 17.51 m2/g, respectively. Fe2O3-water nanofluids was relativly stable with zeta potential of -39.60 mV; -46.37 mV and -41.57 mV, respectively for 500 ºC, 600 ºC and 700 ºC calcination temperature. The viscosity of Fe2O3-water nanofluids was higher than the viscosity of water. The critical heat flux (CHF) value of water-Fe2O3 nanofluids was higher than the CHF water. The highest CHF value for nanofluids was obtained by using α-Fe2O3 nanoparticles with calcination temperature of 600 ºC which 34.99 % of increment compare to the base fluid (water).
Determination of Vitamin C in Various Colours of Bell Pepper (Capsicum annuum L.) by Titration Method Nerdy Nerdy
ALCHEMY Jurnal Penelitian Kimia Vol 14, No 1 (2018): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.14.1.15738.164-178

Abstract

Vitamin C is needed by human body to improve the immune system and can be obtained from the bell pepper. Bell pepper has a different color according to the level of maturity, ranging from green, yellow, orange, and red. Differences in color also make possible differences in vitamin C content. The purpose of this study was to determine vitamin C levels in various colors of bell fruit. Measurement of vitamin C was done by titration method with metaphosphoric acid as the solvent and 2,6 dichloroindophenol as the standardized solution. The samples used were green bell pepper, yellow bell pepper, orange bell pepper, and red bell pepper taken from Gundaling, Berastagi, Karo, Sumatera Utara, 22152, Indonesia. The results show that vitamin C level in various colors of bell pepper respectively, for green bell pepper 16.52 mg vitamin C per 100 g green bell pepper; yellow bell pepper 159.61 vitamin C per 100 g yellow bell pepper; orange bell pepper 121.38 vitamin C per 100g orange bell pepper; red bell pepper 81.19 vitamin C per 100 g red bell pepper. These results indicate that different levels of bell pepper maturity have different vitamin C content.
Study of Conformational Preferences of Erythro-Carolignan E Assessed By The Coupling Between H7'-H8' in Different NMR Solvents Rudiyansyah Rudiyansyah; Ajuk Sapar; Masriani Masriani
ALCHEMY Jurnal Penelitian Kimia Vol 11, No 1 (2015): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.11.1.99.1-7

Abstract

Erythro-carolignan E (1) has been obtained from the ethanol extract of the wood bark of Durio affinis Becc. This research was conducted in order to prove that conformational preferences of compound 1 were solvent dependent. On the basis of 1H-NMR data, the relative configuration of compound 1 was characterized by a coupling constant (3JHH) value of 3.3 Hz at H-7' in CDCl3. The coupling constant (3JHH) values of H-7' in compound 1 has changed to 4.1 Hz and 5.3 Hz in pyridine-d5 and acetonitrile-d3 respectively. As a result, the conformation of compound 1 at C7'-C8' has changed in different NMR solvents.  In conclusion, structure oferythro-carolignan E that contains a dihydroxy group at C7'-C8' is able to change in different NMR solvent.
Effectiveness of Gelatin Extracted from Chicken Claws as A Natural Preservatives for Beef and Fish Ganjar Fadilah; Pramudita Putri Kusuma; Teguh Endah Saraswati
ALCHEMY Jurnal Penelitian Kimia Vol 10, No 2 (2014): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.10.2.544.195-206

Abstract

Gelatin  has  been  successfully  extracted  from  chicken  clawsby  acid  hydrolysis method through four major stages of degreasing, demineralization, extraction and drying. The yield of  extracted  gelatin obtained  from wet chicken claws  was about 6.21  %  (w/w). The  effectiveness  of  gelatin  as  preservative  applied  in  beef  and  fish  was  physically, chemically and microbiologically  studied  by  organoleptic  analysis,  peroxide test, bacteria inhibition  test  and  number  calculation, respectively. Organoleptic analysis by hedonic  test shows  there  were significant  differences  for  color  and  texture  parameters  between  gelatin coated  samples  and control  samples  at  concentrations  of  1:1  (w/w).  Peroxide number analysis  by  iodometry  indicates  the  use  of  gelatin  in  the  preservation  of  meat  and  fish decreased the oxidation number. The result of inhibition test againts Staphylococcus aureus bacteria  shows  the  gelatin  concentration  of  20  %  provided  greatest  halo  zone  diameter (inhibitory  region)  as  19.44  ±  2.11  mm. The colony bacteria test shows the use of gelatin potentially  inhibited  the growth  of  bacteria  up to  75  %.  Overall,  the results  conclude  that gelatin  extracted from chicken claws  has the potential  activities  as a  natural preservative for beef and fish.

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