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M. Widyo Wartono
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widyo@mipa.uns.ac.id
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alchemymipauns@gmail.com
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Kota surakarta,
Jawa tengah
INDONESIA
ALCHEMY Jurnal Penelitian Kimia
ISSN : 14124092     EISSN : 24434183     DOI : -
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
SYNTHESIS OF ACTIVATED CARBONS ORIGINATED FROM ORANGE PEEL BY SUBCRITICAL CO2 ACTIVATION METHOD Arenst Andreas Arie; Emerentina Maerilla Puspaningrum; Henky Muljana
ALCHEMY Jurnal Penelitian Kimia Vol 12, No 1 (2016): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.12.1.944.61-69

Abstract

Low-cost and environmental friendly activated carbons were synthesized from orange peel waste by carbonization followed by activation process using supercritical carbon dioxide. The carbonization process of orange peel waste was conducted in the electrical furnace at temperature of 800 °C for 2 h. Activation process of the impregnated orange peel was carried out in the tubular furnace for 1 h at activation temperature of 140 °C and pressure variation of 80, 125 and 170 bar. Activated carbon with highest surface area of 262.173 m2/g was obtained by co2 pressure of 125 bar. The activated carbons were then utilized as adsorbents for removal of methylene blue (MB) from aqueous solution. The batch adsorption study was carried out by varying the initial concentration of mb solution (2, 4, 6, 8 and 10 ppm). Experimental results showed that the adsorption kinetic of mb fitted the pseudo-second-order rate equation, where as for the adsorption isotherm model followed two models i.e. The dubinin- radushkevich and freundlich model. The adsorption mechanism was found to be governed by the intraparticle and surface diffusion mechanism.
CATALYTIC ACTIVITY CoMo/USY ON DEOXYGENATION REACTION OF 4-METHOXYPHENOL IN BATCH REACTOR Khoirina Dwi Nugrahaningtyas; Irma Fadhila Putri; Eddy Heraldy
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.13.1.2378.66-74

Abstract

This research was conducted to study the effect of catalyst type of CoMo/USY and the reaction time on the deoxygenation reaction of 4-methoxyphenol. The catalyst type used were CoMo/USY, Co-Mo/USY, and Mo-Co/USY. The product was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The activity of the Co-Mo/USY catalyst is higher than CoMo/USY and Mo-Co/USY, it can be seen from the value of total yield and the selectivity. The Co-Mo/USY catalysts shows a significant increasing on the total yield percentage (from 3.71 % to 9.41 %) during catalytic testing. The Co-Mo/USY catalyst has a highest selectivity toward 1,4-dimethoxybenzene product when the reaction time was one hour (0.92 %) and selectivity toward 1,4-dihidroxybenzene when reaction time two hours (0.43 %).
GALLIC ACID PRODUCTION FROM WASTE LOCAL FRUIT IN LOMBOK ISLAND ENZYMATICALLY Eka Junaidi; Yunita Arian Sani Anwar
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.13.2.5118.262-273

Abstract

Tannase is industrially important enzyme used in the production of gallic acid. Gallic acid possesses wide range of biological activities such as`antioxidant, antibacterial, and antivirus. This work aims to produce gallic acid from local fruit rind in Lombok enzimatically. The tested rind local fruit were juwet (Syzygium cumini), kepundung (Baccaurea racemosa Muell.Arg) and mangosteen (Garcinia mangostana). The result showed that tannase activity of 57.827 U/mg. Gallic acid concentration has increased with increase in amount of tannase and reaction time. Optimal gallic acid concentration was obtained at 1 % (v/v) tannase and 60 minutes of reaction time for kepundung rind. However, juwet and mangosteen rind produced optimal gallic acid at 1.2 % (v/v) tannase with the same of reaction time.
Uji Aktivitas Antioksidan N-Metil Kitosan Berkelarutan Tinggi Mardiyah Kurniasih; Purwati Purwati; Ratna Stia Dewi; Susi Fatimah
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.14.1.15100.107-118

Abstract

Telah dilakukan uji aktivitas antioksidan dari N-metil kitosan yang memiliki kelarutan tinggi. Uji aktivitas antioksidan dilakukan dengan menggunakan metode DPPH (1,1-diphenyl-2-pikrilhidrazil) dan metode FTC (ferric thiocyanate). Optimasi sintesis dilakukan untuk memperoleh N-metil kitosan dengan kelarutan tinggi. Hasil penelitian menunjukkan bahwa N-metil kitosan yang berkelarutan paling tinggi adalah N-metil kitosan yang disintesis dengan 1,7 mL formaldehid 10%. Berdasarkan hasil uji aktivitas antioksidan menggunakan metode DPPH dapat diketahui bahwa N-metil kitosan merupakan antioksidan sedang dengan nilai IC50 sebesar 145,398 ppm. Hasil pengujian antioksidan metode FTC menunjukkan bahwa N-metil kitosan memiliki kemampuan menghambat terbentuknya senyawa radikal bebas yang disebabkan oleh oksidasi asam lemak.An Antioxidant Activity Test of High Solubility N-Methyl Chitosan. An antioxidant activity test of high solubility N-methyl chitosan has been performed. The antioxidant activity test was performed using DPPH (1,1-diphenyl-2-pikrilhidrazil) and FTC method (ferric thiocyanate). The synthesis optimization was performed to obtain high N-methyl chitosan solubility. The results showed that N-methyl chitosan with the highest solubility in 1% acetic acid solvent was N-methyl chitosan which was synthesized with 1.7 mL formaldehyde 10%. Based on the results of antioxant activity test using DPPH method can be seen that N-methyl chitosan is a medium antioxidant with IC50 value of 145.398 ppm. The result of antioxidant test of FTC method showed that N-methyl chitosan has antioxidant activity with tendency to increase along with the increase of N-methyl chitosan concentration.
Isolation and Identification of β-Sitosterol and Stigmasterol Mixture from Root Bark of Slatri (Calophyllum soulattri Burm. f) Doni Eko Saputra; Nestri Handayani; Muhammad Widyo Wartono
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.10.1.14.87-93

Abstract

Chemical isolation and identificationof root bark of CalophyllumsoulattriBurm. f. have been conducted. Isolation was conducted by maceration with ethyl acetate as solvent. Ethyl acetate extract was separated and purified by vacuum liquid chromatography and flash chromatography which was guided by thin layer chromatography to obtain yellowish white solid. Isolated compounds were determined by spectroscopy methods such as UV, FTIR, 1H NMR, 13C NMR, DEPT, HSQC, HMBC and were compared to the references. Based on the analysis result it’s known that the compounds are the mixture of?-sitosterol and stigmasterol.
Synthesis And Characterization Of Complex Diaquadihydantoin Nickel(II) Sulfat Monohidrat Sentot Budi Rahardjo; Surya Dewi Marliyana; Nur Asih Siwi Wulandari
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.10.2.534.137-148

Abstract

The purpose of the research is to find out the synthesis, formula and characteristic of complex of Nickel(II) with hydantoin (hyd). Complex of nickel(II) with  hydantoin  have been synthesized in 1 : 1 mole ratio of metal to ligan in methanol.The formula of  complex which are predicted from analysis of % Ni in complex by Atomic Absorption Spectroscopy (AAS) is Ni(hyd)2(H2O)3.SO4.  Ratio  of  cation  and  anion  of  complex  is  measured  by conductivitymeter  correspond to 1: 1.  The thermal analysis  is determined  by Differential Thermal  Analyser  (DTA)  indicate  that  complex  contain  some  hydrate,  thus  possibility formula  of  complex  is  [Ni(hyd)2(H2O)2]SO4.H2O (Diaquadihydantoinnikel(II) sulfat monohidrat).  Data  of  infra  red  spectra  show  a  shift  of  N-H  group  and  tertier  N  group 138 absorption  and  indicate  this  functional  group  coordinated  to  the  center  ion.  Magnetic Suscepbility measurement show that the complex is paramagnetic with μeff  = 3.2  BM. The UV-Vis spectra appear do to 2 transition peak on  λ  =  740 nm (13,513 cm-1) and  405 nm (24,691 cm-1).  The peak indicate that structure of complex is octahedral with transition 3A2g→ 3T1g(P)(ν2) andtransition 3A2g  → 3T1g(F)(ν3). One peak which  is  not appear is transition 3A2g → 3T2g (F)(ν1) which also estimate of 10 Dq (Δ0) is 103.615 kJ mol-1.
Effect of Garlic Powder Addition to Gelatin Biocomposite on Its Antibacterial Activity Pramudita Putri Kusuma; Ganjar Fadillah; Husna Syaima; Teguh Endah Saraswati
ALCHEMY Jurnal Penelitian Kimia Vol 12, No 1 (2016): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.12.1.930.1-13

Abstract

The addition of garlic powder to gelatin from chicken claw waste was potentially developed as a natural preservative in food, especially for meat. Preparation of gelatin/garlic biocomposite was performed in three stages: synthesis of gelatin from chicken claw, garlic powder preparation as allicin source and preparation of biocomposite gelatin/garlic. The preparation of dry biocomposites was done by weighing the gelatin and garlic powder in weight ratio of 1 : 1 and 1 : 2 (w/w) in the total mass of 0.75 grams. For wet biocomposite preparation, the mixture of the powder was solved in 5 mL of lactic acid 2 %. Functional groups of gelatin, garlic and biocomposite were analyzed by fourier transform infrared spectroscopy (FTIR). The antibacterial activity of biocomposite against Staphylococcus aureus were tested using disc diffusion method. This test was performed on garlic powder, solvent and gelatin/garlic biocomposites powder in the ratio of 1 : 1 and 1 : 2 in 2 % lactic acid solvent. The biocomposite with a weight ratio of gelatin : garlic of  1 : 1 had the optimum diameter of inhibition zone. The effectiveness of biocomposite gelatin/garlic as natural preservative applied in meat was also physically studied by organoleptic analysis. Organoleptic analysis through the hedonic test was conducted on the parameters of color, smell, and texture of gelatin/garlic biocomposites-coated meat. The results showed that the addition of garlic can increase the effectiveness of gelatin as a natural preservative of meat for four days stored in closed packaging at room temperature.
KAJIAN AKTIVASI H2SO4 TERHADAP PROSES PEMILARAN Al2O3 PADA LEMPUNG ALAM Khoirina Dwi Nugrahaningtyas; Dian Maruto Widjonarko; Daryani Daryani; Yunita Haryanti
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.12.2.1312.190-203

Abstract

Telah dilakukan penelitian tentang lempung alam (bentonit) yang diaktivasi dengan berbagai variasi konsentrasi H2SO4, dan dengan proses interkalasi menggunakan larutan Al2O3.H2O. Tujuan dari penelitian ini adalah untuk menentukan konsentrasi optimum untuk aktivasi lempung, berdasarkan karakter persentase montmorillonite dan keasaman total. Hal ini juga didukung oleh karakterisasi setelah proses interkalasi, yaitu karakter luas permukaan spesifik, volume pori total, radius pori rata-rata dan kandungan aluminium. Analisis persentase-Montmorilonit dilakukan dengan menggunakan difraksi sinar X; keasaman total ditentukan secara gravimetri; luas permukaan spesifik, volume pori total, dan jari-jari pori rata-rata diukur dengan Surface Area Analyzer NOVA dan kandungan aluminium ditentukan oleh Analisis Aktivasi Neutron.Hasil penelitian menunjukkan bahwa aktivasi optimum pada konsentrasi H2SO4 1,5 M mempunyai persentase montmorillonite optimum (91.335%) dan nilai keasaman meningkat 193.955% dari nilai keasaman bentonit alam. Karakter fisik dan kimia setelah interkalasi juga menunjukkan bahwa terjadi peningkatan kadar aluminium (57,540%), luas permukaan spesifik (150,586%), volume total pori (73,236%) dan keasaman Total (203,504%) dari bentonit alam. Rerata jejari pori mengalami penurunan 10,274% setelah aktivasi dan penurunan 30,868% setelah proses interkalasi.
SYNTHESIS AND CHARACTERIZATION OF CERAMIC METAL Ni-YSZ PREPARED FROM LOCAL ZIRCON SAND AT VARIOUS Ni:YSZ COMPOSITION Karima Apriany; Fitria Rahmawati; Eddy Heraldy; Dani G Syarif; Syoni Soepriyanto
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.13.2.2384.217-229

Abstract

This research synthesized a cermet Ni-YSZ, in which the YSZ (yttria stabilized-zirconia) was synthesized from the local zircon sand, ZrSiO4, as a side product of tin mining plant in Bangka island, Indonesia. The synthesized YSZ in this research is zirconia, ZrO2 doped by 8 % mol of yttrium dioxide. The synthesis used solid state reaction method and the result was characterized its crystal structure and its cell parameters by XRD analysis equipped with Le Bail refinement, surface morphology analysis, and an impedance analysis to understand its ionic conductivity. The cermet Ni-YSZ was synthesized at a various composition of Ni:YSZ i.e., 20:80, 30:70, and 40:60 (b/b). The analysis shows that Ni-YSZ is in two phases of Ni and YSZ without any presence of a third phase. It indicates that there was no solid state reaction between Ni and YSZ during synthesis. In this Ni-YSZ cermet, the Ni phase in a cubic structure, and the YSZ is also in a cubic structure. Morphological study shows that the addition of Ni to YSZ allows the morphology to become more roughness with larger grain size. This research found that the Ni-YSZ 20:80 has highest ionic conductivity.
Pelarutan Selektif Tembaga dari Limbah Printed Circuit Board dengan Hidrogen Peroksida Gatut Ari Wardani; Rokiy Alfanaar; Sri Juari Santosa
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.14.1.11168.51-59

Abstract

Pelarutan selektif tembaga dari limbah printed circuit board (PCB) telah berhasil dilakukan. Logam tembaga yang terkandung di dalam papan PCB dapat dipisahkan menggunakan campuran hidrogen peroksida dan asam sulfat dengan variasi perbandingan volume 0 : 1, 1 : 1, 2 : 1, 3 : 1, 4 : 1, dan 5 : 1. Pemisahan optimal dilakukan dengan sistem perendaman selama 3 hari dengan campuran H2O2/H2SO4 = 3 : 1 (v/v). Jumlah tembaga yang terkandung di dalam papan PCB dianalisis menggunakan X-ray fluorescense. Tembaga yang terkandung di dalam PCB sebesar 57,7%. Pelarutan selektif dapat menurunkan kadar tembaga sehingga tembaga yang masih tersisa adalah sebesar 7,7 x 10-4 %. Penurunan kadar tembaga yang terkandung di dalam PCB mencapai 99,999%. Analisis spektrometri serapan atom dilakukan untuk mengetahui jumlah tembaga yang terlarut yaitu sebesar 25,415 mg/kg PCB.Leaching of Copper from Printed Circuit Board Waste with Hydrogen Peroxide. Leaching of copper from printed circuit board (PCB) waste has been successfully performed. The copper metal contained in the PCB can be separated using a mixture of hydrogen peroxide and sulfuric acid with a variation of volume ratio is 0 : 1, 1 : 1, 2 : 1, 3 : 1, 4 : 1, and 5 : 1. Optimal separation is carried out by the immersion system for 3 days using H2O2/H2SO4 = 3:1 (v/v). The amount of copper contained in the PCB was analyzed using X-ray fluorescence. The copper contained in the printed circuit board is 57.7%. The leaching process can decrease the copper content so that the remaining copper is 7.7 x 10-4%. The decrease of copper content contained in PCB reaches 99.999%. Analysis of atomic absorption spectrometry was conducted to determine the amount of dissolved copper that is 25.415 mg/kg PCB.

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