Articles

Found 20 Documents
Search

SENG OKSIDA (ZnO) SEBAGAI FOTOKATALIS PADA PROSES DEGRADASI SENYAWA BIRU METILEN Darajat, Syukri; Aziz, Hermansyah; Alif, Admin
Jurnal Riset Kimia Vol 1, No 2 (2008): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v1i2.72

Abstract

 ABSTRACT A research aimed to study the influence of ZnO white powder on photodegradation of methylene blue using Merkuri lamp (l = 365 nm) as light source have been reached. A suspension of ZnO (40 mg) mixed with 25 mL of methylene blue solution (initial concentration of 0.015 mM) then was illuminated for 60 minutes showed degradation and quantum yield amounting 23.84% and 3.55 molecules photon-1, respectively. These results mean that by using ZnO as photocatalyst there is about four times efficiency than the one without ZnO either in case of time consumed or the number of photon applied. In kinetic study, it has been observed that such semiconductor-catalyzed photochemical reaction obeys the first order rule where rate constant and half time consecutively were 0.0029 minute-1 and 231 minutes.  Keywords : photodegradation, photocatalyst, quantum yield, semiconductor, photochemical reaction.
EKSTRAK METANOL DARI DAUN MAHKOTA DEWA (Phaleria macrocarpa) SEBAGAI INHIBITOR KOROSI BAJA DALAM ASAM KLORIDA Rahmi, Azimatur; -, Emriadi; Alif, Admin
Jurnal Riset Kimia Vol 7, No 2 (2014): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v7i2.168

Abstract

Vol 7 No 2ABSTRACTExtract of Phaleria macrocarpa leaves have been studied as corrosion inhibitor for mild steel ofhydrochloric acid solution 2.0 N. The efficiency of inhibition was evaluated by gasometric methodand electrochemical analysis. The temperature and concentration effects on the inhibitorsperformance were also investigated. The result obtained showed that the extract is one of promisingcandidate as an inhibitors for the corrotions of mild steel in HCl media, inhibition efficiencyincrease as the extract concentration is evaluated. The activation energy (Ea) increase with theaddition of the extract. Where inhibition of extract on the steel surface obey modified Langmuirisotherm equation. Potentiodynamic polarization curve indicated the Phaleria macrocarpa leavesextract play role as the anodic type inhibitor.Keywords : Corrosion inhibition, mild steel, Phaleria macrocarpa, hydrochloric acid.
PEMBENTUKAN HIDROGEN DARI AIR SECARA FOTOKATALITIK OLEH SERBUK TIO2 YANG DIDOPING NITROGEN Arfi, Febrina; Aziz, Hermansyah; Alif, Admin
Jurnal Kimia Valensi Jurnal Kimia VALENSI Volume 2, No. 2, November 2016
Publisher : Lembaga Penelitian dan Pengabdian Kepada Masyarakat Syarif Hidayatullah State Islamic Uni

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (568.005 KB) | DOI: 10.15408/jkv.v2i2.3077

Abstract

Abstrak   Kesadaran terhadap ancaman krisis energi karena kebutuhan yang sangat besar dan pencemaran lingkungan yang terjadi, maka perlu dilakukan penelitian untuk menghasilkan sumber energi alternatif. Hidrogen merupakan energi alternatif yang dapat digunakan sebagai bahan bakar, ramah lingkungan, dan dihasilkan dari sumber yang melimpah di bumi  yaitu air. Salah satu metode yang dipakai untuk memproduksi gas hidrogen adalah metode fotolisis. Katalis yang digunakan adalah TiO2 yang didoping N, tujuannya mempelajari pengaruh variasi perbandingan TiO2/N terhadap aktifitas fotokatalitik pembentukan hidrogen. Hasil penelitian memperlihatkan produksi gas menggunakan TiO2/N pada kondisi optimum terjadi pada perbandingan 4:6 yang menghasilkan gas 2.2 mL. Dari hasil penelitian dapat disimpulkan bahwa TiO2 doping N dapat membantu pembentukan gas secara fotokatalitik.   Kata kunci : Fotolisis, katalis, doping, fotokatalitik Abstract The awareness about energy crisis is rising quickly. Consider to the very fast growing need of energy and the environmental impact caused by the conventional energy, so that the research about renewable energy as an alternative energy resource is very urgent. Therefore, the research to produce hydrogen as an alternative energy resourse was conducted. Hydrogen can be used as a green fuel which can be extracted from water, a huge amount of resource on the earth. In this research, the photolysis method was used. Nitrogen-doped TiO2 catalyst was used in order to analyse the influence of variational ratio of TiO2/N to the photocatalytic process of hydrogen production. The result shows that the optimum condition in producing gas using TiO2/N occured at the ratio 4:3 which produced as much as 2.2 ml gas. From this result can be concluded that Nitrogen-doped TiO2 supports the extraction of gas in photocatalytic process.   Keywords: Photolysis, catalys, doped, photocatalytic   DOI: http://dx.doi.org/10.15408/jkv.v0i0.3077
MODIFIKASI DAN KARAKTERISASI TITANIA (M-TIO2) DENGAN DOPING ION LOGAM TRANSISI FENI DAN CUNI Rilda, Yetria; Arief, Syukri; Dharma, Abdi; Alif, Admin
Jurnal Natur Indonesia Vol 12, No 2 (2010)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat Universitas Riau

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (632.25 KB) | DOI: 10.31258/jnat.12.2.178-185

Abstract

Structure and size of titania nanoparticles have been modified with doping the transition metal (FeNiand CuNi) and controlling the calcinations temperature. Gel and M-TiO 2 powder were characterized byFT-IR showed the changed in intensity at 4000-400 cm-1. TG-DTA curve show the weigh of sample wasdecreased with the increasing of temperature 25-800°C. XRD pattern used to identify the titania structureshows the highest intensity of anatase at temperature calcination as 500°C. XRD of FeNi-TiO 2 and CuNi-TiO2 FeNi 10.5-41.9 nm and CuNi 12.1-33.5 converted using Debye-Scherrer?s equation and TEM analysisthe distribution of crystal size as FeNi-TiO2 and CuNi-TiO2 10-15 nm. SEM has shown that morphology ofdifferent surface from the FeNi-TiO 2 and CuNi-TiO 2 at different calcinations temperatures. Titaniacomposition can be determined by EDX analysis give as FeNi-TiO2 1:1, 97.01% and CuNi-TiO2 1:1, 94.63%respectly. The surface area has been determined by BET as FeNi-TiO 2 was 64.38 m2/g and CuNi-TiO2was 40.9 m2/g.
SINTESIS DAN APLIKASI KARBOKSIMETIL KITOSAN SEBAGAI INHIBITOR KOROSI PADA BAJA KARBON DALAM AIR Erna, Maria; Emriadi, Emriadi; Alif, Admin; Arief, Syukri; Noordin, Mohd Jain
Jurnal Natur Indonesia Vol 12, No 1 (2009)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat Universitas Riau

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (351.132 KB) | DOI: 10.31258/jnat.12.1.87-92

Abstract

Carboxymethyl chitosan (CMC) was synthesized with different methods by reacting chitosan with monochloroaceticacid in the presence of sodium hydroxide under variation conditions. The above samples were characterized byFourier transform infrared spectroscopy (FTIR) and soluble in water in range of pH. The CMc were soluble in watera wide range of pH and applied as corrosion inhibitor for steel in water. The inhibiting influence of CMC was studiedby potentiodynamic polarization method. It was found thad corrosion rate was dependent on water pH and CMCconcentration. The results show that optimum the inhibition efficiency at pH 5 and 1 ppm concentration CMC, i.e.,77%. The adsorption of used compound on the steel surface obeys modified Langmuir isotherm. Polarizationmeasurement show that the CMC acts essentially as a anodic-type inhibitor.
EFEKTIFITAS KITOSAN SEBAGAI INHIBITOR KOROSI PADA BAJA LUNAK DALAM AIR GAMBUT Erna, Maria; Emriadi, Emriadi; Alif, Admin; Arief, Syukri
Jurnal Natur Indonesia Vol 13, No 2 (2011)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat Universitas Riau

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (70.13 KB) | DOI: 10.31258/jnat.13.2.118-122

Abstract

This research is intended to learn inhibition efficiency of mild steel corrosion in peat water using two type ofchitosan. First chitosan is without treatment and the second one is synthesized by ionotropic gelation method andthen is characterized by Fourier transform Infrared spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM).Diameter of chitosan porous is about 500 nm which is measured based on morphological photo using SEM withinhomogeneous porous shape and porous distribution is unsmooth . Effect of chitin and chitosan on the corrosionof mild steel in peat water is studied using weight loss method. It is found that corrosion inhibition efficiencydepends on peat water pH, inhibition technique and interaction time. The results show that inhibition efficiency ofchitosan without treatment and with treatment are 88.73% and 93.32% respectively. The inhibition is assumed tooccur via physicsorption of the chitin and chitosan molecules on the metal surface. The Langmuir adsorptionisotherm is tested for their fit to the experimental data.
PENARIKAN ION Cu2+ (CuSO4) DARI LARUTAN AIR MELALUI PROSES ELEKTROLISIS SECARA FOTOVOLTAIK DENGAN SEMIKONDUKTOR LAPISAN OKSIDA CuO DAN ZnO DARI KUNINGAN Alif, Admin; Suyani, Hamzar; Suyani, Hamzar
Jurnal Riset Kimia Vol 5, No 2 (2012): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v5i2.222

Abstract

Photovoltaic is a method that can convert sunlight energy into electrical energy. One use ofphotovoltaic electrolysis can be used for metal ions contained in the liquid waste. The research aims electrolyzing Cu2+ ions from aqueous solution using a series of photovoltaic cells with semiconductor CuO and ZnO oxide layer of brass with Na2SO4 electrolyte. The series of photovoltaic cells is associated with an electrolysis cell containing Cu2+ ions to be electrolysed. Semiconductor electrodes made with brass burning in a furnace in a few repetitions at a temperature of 400°C for 1 hour. U-shaped electrolysis cells glass tube containing a solution of CuSO4 1.25 g/L using a carbon rod as anode and cathode. Electrolysis of Cu2+ ions results were analyzed by Atomic Absorption Spectrofotometer (AAS). The results showed that the optimum conditions Na2SO4 electrolyte concentration 0.8 N with semiconductor double-furnace with a strong current 0.829 mA and a voltage of 0.241 mV, the value of efficiency of conversion of solar energy into electrical energy is 0.599%. Electrolysis of Cu2+ ions for 4 weeks could reduce Cu2+ ions concentration of 35 mg/L to 15.909 mg/L (45.45%). CuO and ZnO electrodes was relatively less stable and cause strong currents and voltage drop along the length of the process.
Penentuan Kondisi Optimasi Transpor Ion Cu (Ii) Melalui Teknik Membran Cair Fasa Ruah Secara Simultan Dengan Oksin Sebagai Pembawa -, Refinel; Alif, Admin; Octarini, Rizki
Jurnal Riset Kimia Vol 4, No 2 (2011): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v4i2.130

Abstract

 ABSTRACT Determination of optimum condition and kinetic analysis Cu (II) iontransport by simultaneous bulk liquid membrane has been studied. Optimum condition for resource phase with Cu (II) ion concentration as 3,147 x 10-4 M obtained at pH 3 receiving phase with H2SO4 concentration 0,15 M and transport time as long as 3 hours through chloroform membrane using oxine 17,5 x 10-4 M as carrier. Transportation rate of Cu (II) ion decided by comparasion changer-over rest concentration in resource phase Rs and transpoted to receiving phase Rp and then monitored by Atomic Adsorbtion Spectrophotometre (AAS). Kinetic of transport Cu (II) ion process by simultaneous bulk liquid membrane technique fulfil irreversible consecutive first order reaction with transport Cu (II) ion gave (k1) value as 0,0442 minute-1 and ( k1 ) 0,0372 minute-1 . Simultaneous bulk liquid membrane method can be the alternative method in the determination of optimum condition and kinetic analysis of metal ions transport. Key words: Cu (II) ion, kinetic, optimum, transport, liquid membrane, simultaneous    
OPTIMALISASI TRANSPORT SELEKTIF ION Ni(II) TERHADAP Cd(II) DENGAN ZAT PEMBAWA OKSIN MELALUI TEKNIK MEMBRAN CAIR FASA RUAH SECARA SIMULTAN Ningsih, Vera Tri; Alif, Admin; Aziz, Hermansyah
Jurnal Riset Kimia Vol 2, No 2 (2009): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v2i2.159

Abstract

  ABSTRACT The selective transport of Ni(II) to Cd(II) through simultaneously liquid membrane technique has been investigated. The cell membrane was made by mixturing Ni(II) and Cd(II) ions at concentration as 3.41x10-4 M and 1.78x10-4 M respectively as source phase, oxine in chloroform as membrane phase and Na2EDTA solution as receiving phase. Concentration of recidual Ni(II) and Cd(II) ions in source phase transported to receiving phase was measured by Atomic Absortion Spectrofotometry (AAS). The results showed the at optimum condition of Ni(II) and Cd(II) transport occurred at source phase of pH 7, oxine concentration 0.001 M in chloroform and 0.04 M Na2EDTA solution pH 7. In this condition, Ni(II) and Cd(II) transport selectivity was found 80.89%. From the experiment, it was found that the transport rate constant from source phase to membrane phase (k1) for Ni(II) (0.7544 per hour) smaller than Cd(II) (1.3800 per hour ), on the other hand the transport rate constant from membrane phase to receiving phase (k2) Ni(II) (2.7580 per hour) greater than Cd(II) (1.3790 per hour). The phase-to-phase transport of Ni(II) and Cd(II) was consecutive first order reaction.  Keywords : bulk liquid membrane, oxine, technique    
PEMECAHAN (SPLITTING) MOLEKUL AIR MENJADI GAS H2DAN O2 MELALUI PROSES FOTOVOLTAIK Fatmi, Dini; Alif, Admin; Suyani, Hamzar
Jurnal Riset Kimia Vol 5, No 2 (2012): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v5i2.209

Abstract

One method to overcome the scarcity of alternative sources of energy on earth is through the development of photovoltaic cells. This method used a solar energy to electrical energy transformation. In this research, breaking (splitting) of water molecules into H2 and O2 gas by the photovoltaic process uses electrodes CuO/C with Na2SO4 electrolyte. In this process used 2 photovoltaic cells as electricity producing and U-shaped electrolysis cell for solver (splitting) of water molecule produce H2 and O2 gas. CuO electrode (anode) is made through the burning of copper rod in a furnace at temperature 400 oC with a variety of combustion 1, 3, 4 times each lasting for 1 hs, while the cathode in the form of carbon rods obtained from 2B pencil. The optimum conditions for Na2SO4 electrolyte concentration is 0.8 N and for CuO electrodes with 3x burning. Optimum efficiency photovoltaic process was 2.66%. H2 and O2 gas volume obtained near stoichiometric ratio is 2 : 1.