Jurnal Riset Kimia
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PRODUKSI BIOETANOL DARI SAMPAH DEDAUNAN SEKITAR KAMPUS UNAND DENGAN METODE SSF (SIMULTANEOUS SACHARIFICATION FERMENTATION)
Vol 7 No 2ABSTRACTIn this research, cellulose from waste leaves are conversed into ethanol by SSF technologyusing cellulase from Trichoderma viride strain T1 sk. In saccharification process, cellulasebreaks cellulase polymer into glucose. Simultaneously, the formed glucose is conversed intoethanol by invertase produced by Saccharomyces cerevisiaewhich is grew on YPD medium.Waste leaves are pretreatmented using basic solutions : basic NaOH 1 %, NH4OH 8 %, NaOH 1% + NH4OH 4 % and NaOH 1 % + NH4OH 8 % with ratio of solid mather (sample) : liquid(basic solution) 1:10 (w/v) with volume of basic solution 100 mL. Immersion time is variatedfor 24, 48 and 72 hours on 500C. The result of research shows that the use of NaOH 1% +NH4OH 4% gives the highest glucose concentration 933,75 μg/mL with immersion time for 72hours on 500C. After being pretreatmented, sample of 0,4 g waste leaves produce the highestglucose concentration. Measurement by GC/MS shows ethanol concentration 62,41% onfermentation time 96 hours with volume of ethanol 2,45 mL for 0,4 g sample.Keywords : Waste leaves, Pretreatment, Trichoderma viride strain T1 sk, SSF, Bioethano
MEMPELAJARI KONDISI OPTIMUM PEMBUATAN BIOETANOL MELALUI HIDROLISIS ENZIMATIS MENGGUNAKAN Sacharomycess cereviceae DARI PATI SAGU DAN UMBI TALAS
Vol 5 No 1ABSTRACT Sago (Metroxylon sp) and umbi talas (Colocasia gigantea Hook F) are natural resources that are found in plantyfull Indonesian. However, these potencies are not yet processed to give an optimum value added product. Sago and taro are rich of starch, that could be fermented to form bioethanol for reneweable energy. The ethanol were produced by fermenting the hydrolized starch of sago and taro with yeast. The starch of sago and taro were hydrolized enzymaticly by α-amylase and glucoamylase. Sago and taro (15 g each) were grinded and hydrolized by α-amylase and then by glucoamylase at the variation of volume of 4, 5, 6, 7, and 8 mL for 1, 2, 3, 4, and 5 hours. The glucose produced was measured by Somogy-Nelson methods. The product of sago hydrolysis were optimum with 6 mL of α-amylase and 6 mL glucoamylase for 2 hours to give 59.11 g/L of reducing sugar. The product of taro with 6 mL α-amylase and 7 mL glucoamylase for 4 hours which gave 64.22 g/L of reducing sugar. The product of ethanol were analyzed by Gas Cromatography (GC). The maximum bioethanol production obtained optimum after 4 days fermentation of hydrolized sago starch and after 5 days fermentation of hydrolized taro starch which were 3.742% and 4.0123%. Key words: Bioethanol, sago starch, taro, enzymatic hydrolysed, α-amylase and glucoamylas
PENGARUH BEBERAPA PERLAKUAN TERHADAP PENGURANGAN KADAR FORMALIN PADA IKAN YANG DITENTUKAN SECARA SPEKTROFOTOMETRI
The case of how handling the fresh fish which used the dangerous chemical material (formaldehyde) is still found in society, so that is why it is necesarry to find the safety way to handle the fresh fish in. It has been held the research about the influence of on the effect of some treatment in reduction the formaldehyde level on fish determined by spectrophotometry UV-Visible at wavelength 412 nm and 40°C. In the preliminary research the fish is soaked in formaldehyde liquid (100 mg/mL) for 24 hours, then washed, soaked and boiled. Then, the filtrate is reacted with Nash reagent. The yellow color which has formed was measured at λ 412 nm. The result shows there is the reduction of formaldehyde level in the sample about 43.9 % after washing, 33.3 % after soaking, 53.8 % after boiling. After that, the fish that was spread in the market which suspected containing the formaldehyde then washed, soaked and boiled. The result shows there is the reduction of formalin level in sample 1 about 22,7 % after washing, 17.0% after soaking, and 96.1 % after boiling. While in sample 2, 41.8 % after washing, 56.2 % after soaking, and 95.4 % after boiling
PEMANFAATAN ABU KULIT KAKAO UNTUK PEMBUATAN BATU BATA
Brick is one of building materials derived from clay. The manufacturing process is with or without the use of substances mixing with the process of combustion at high temperatures. One of the mixing substances is derived from the rind cacao ash and its function is as an adhesive on the bricks.The purpose of this research is to understand the characteristics of brick as effect of cocoa rind as the value of compressive strength, porosity, water absorption and weight of a brick. The main materials of brick production are clays and trass ground which are mixed homogeneous with ratio 1 : 2 by varying cocoa rind ash additional by 5%, 10%, and 15%. The result is the compressive strength of the bricks using rind cocoa ash is 392.2 kg/cm3 higher value than traditional brick is 56.1 kg/cm3
PENGGUNAAN MATRIKS PENDUKUNG (SILIKA GEL) PADA TANAMAN KAYU APU (pistia stratiotes. l) SEBAGAI BIOSORBEN UNTUK MENGURANGI TINGKAT PENCEMAR ION TIMBAL (Pb2+)
 ABSTRACT Problems of environmental became one of problem must be interested by public, One of them was the stain by ion lead (Pb2+). An experiment was conduct about the use of “Kayu Apuâ€Â (Pistia Stratiotes. L) as ion Pb2+ adsorbents before and after added supporting matrix (silica gel). This experiment worked with static method. The parameters were examined carefully: pH (2, 4, 6, 8, and 10), concentrate (10, 25, 50, 75, and 100 ppm), and contacted time (15, 30, 45, 60, and 75 minutes). pH, concentrate, and contacted time optimum for “Kayu Apuâ€Â before using supporting matrix (silica gel) successively 6, 50 ppm, 30 minute, with the adsorbtion efficiency: 89.16%. Besides, pH, concentrate, and contacted time optimum after using supporting matrix (silica gel) successively 4, 50 ppm, 45 minute, with the adsorbtion efficiency: 97.47%. Biomaterial of “Kayu Apuâ€Â has been given supporting matrix (silica gel) more efficiently than without supporter matrixs for adsorbing ion Pb2+.Keywords: pistia Stratiotes. L, biosorbent, silica gel, Pb2
KINETIC MODELING STUDY FOR ACYLATION REACTION OF O-XYLENE TO 3,4-DIMETHYLBENZOPHENONE OVER H-BETA
 ABSTRACTThe reaction of o-xylene with benzoic anhydride has been studied by the changing molar ratio of the reactants (20:1, 10:1, and 5:1) in a batch reactor under reaction temperature 120oC. The reaction carried out without catalyst and also with catalyst Zeolite beta which was activated at 300oC overnight. HPLC analysis results showed that the yield of the product increase with the changing molar ratio of the reactants. An attempt was made in determining the kinetics of the reaction. The results show that the reaction is neither first nor second order in the acylating agent. Obtaining the reaction order even initially is unsuitable for even simple reactions that do not go to completion. It is even less applicable where more than a single process which affects the rate is taking place right from the start. These might be any one or combination of diffusion, adsorption, desorption, inhibition of the reaction by the product and multi step reactions on the surface. Postulated reaction mechanisms may be required in combination with experimental data to determine even initial reaction orders. Key words: o-xylene, catalyst, kinetics, reaction order
ISOLASI DAN ELUSIDASI STRUKTUR TRITERPENOID KULIT BATANG SURIAN Toona sinensis DAN UJI TERHADAP HAMA Crosidolomia pavonana
 ABSTRACT Tryterpenoid compound (3-hydroxyeupha-7-ene) were isolated from hexane fraction the steam bark of Toona sinensis (Meliaceae). The structures of these compounds were established base on spectroscopic evidence, including UV, IR, 3C-NMR, 1H-NMR, HMBC, HMQC and COSY spectra and literature survey this is new compound in family Meliaceae. Insect activity of the hexane fraction (1.0%) and against Crosidolomia pavonana were tested. The activity of hexane were mortality (37.5%), antifeeding (75.5%). The activity of the 3-hydroxyeupha-7-ene showed mortality (52.0%), Lc50; 0.39847 and Lt50; 5.53931. Keywords: Toona sinensis (Meliaceae), 3-hydroxyeupha-7-ene, Crosidolomia pavonana, Antifeeding, Mortality Lc50 and Lt5
AN IN-SYRINGE La CO-PRECIPITATION METHOD FOR PRE-CONCENTRATION OF OXO-ANIONS FORMING ELEMENTS IN SEAWATER FOLLOWED BY ICP-MS MEASUREMENT
Vol. 1 No. 1ABSTRACT A lanthanum (La) co-precipitation method was explored for pre-concentration of oxo-anion forming elements followed by measurement with Inductively Coupled Plasma Mass Spectrometry (ICP-MS).  The co-precipitation and subsequent washing and elution steps were performed in a 25 mL-volume syringe in order to save the sample consumption and to avoid the contamination from the experimental environment.  In the present work, various parameters such as the concentration of La added into the sample solution, the pH, aging time, and so on were optimized to obtain good recoveries and analytical detection limits for V, As, Se, Sb, and W.  Generally, in the co-precipitation method, high concentration of precipitant (in this case, La) causes a serious problem of signal memory effect in ICP-MS measurement. To reduce such memory effect, in the present experiment, high level of La was removed by passing the analyte solution (i.e., lanthanum hydroxide dissolved in 1 M HNO3) through a mini column packed with cation-exchange resins.  The method thus obtained was evaluated through the measurement of V, As, Se, Sb and W in seawater reference materials (CASS-4 and NASS-5). The recoveries exceeded 80%, and the observed values were in good agreement with the certified values. Thus, the present method was applied to the determination of trace elements in real seawater sample.    Keywords: Lanthanum, pre-concentratio
DEGRADASI ZAT WARNA NAPHTOL BLUE BLACK SECARA SONOLISIS DAN FOTOLISIS DENGAN PENAMBAHAN TIO2-ANATASE
 ABSTRACTDegradation of naphtol blue black dye had been done by sonolysis and photolysis with adding anatase-TiO2. Sonolysis method were performed using an ultrasound with frequency 45 kHz, and photolysis using an irradiation of UV light l= 359 nm.  The optimum condition for degradation of 6 mg/L naphtol blue black by sonolysis with addition of 0.1000 g anatase-TiO2 were found at pH = 3.0 and temperature 30 ± 1°C.  Percentage of degradation at pH and temperature optimum was 65.20% within 120 minutes treatment.  Degradation of 6 mg/L naphtol blue black by photolysis with addition of 0.1000 g anatase-TiO2 was optimum at pH=3.0 and percentage of degradation was 68.72% within 120 minutes irradiation without stirring. The combine of sonolysis and photolysis method simultaneously for degradation of naphtol blue black dye by adding anatase-TiO2, achieved 92.51% degradation after 60 minutes treatment. Keywords : sonolysis, photolysis, naphtol blue blac
CHEMICAL COMPOSITION AND ANTIBACTERIAL ACTIVITY OF THE ESSENTIAL OIL OF THE Toona sureni (Blume) Merr
 ABSTRACT The essential oil composition of the Toona sureni (Blume) Merr leaf was analyzed by GC-MS. More than 68 peaks, representing 99.99% of total oil, forty three components were identified, this represents 80.65% of the total oil component. The major components were α-terpinene (9.58%), α-copaene (8.39%), bicyclogermacrene (7.61%), δ-cadinene (6.65%), β-elemene (4.88%), germacrene-D (4.65%), δ-selinene (3.58%), caralene (3.10%), β-caryophyllene (2.88%), α-cubebene (2.82%), δ-gurjunene (2.20%), and (-)-isoledene (2.05%). The antibacterial activity of the essential oil of Toona sureni (Blume) Merr leaf was evaluated using disk diffusion method. The oil was effective on the inactivation of Escherichia coli, Staphylococcus aureus and Bacillus subtilis. Keywords: Toona sureni (Blume) Merr, antibacterial activity, GC-MS, essential oi