Kinetics study of copper (Cu) and chromium (Cr) adsorption using green mussel shells (Perna viridis) adsorbent

Research has been carried out on making green mussel shell adsorbents to absorb Cu and Cr metals. The study of making green mussel shell adsorbents was carried out by thermal activation using a furnace. The results of the activated adsorbent were characterized using FTIR and SEM-EDX. Furthermore, the adsorbent was used to absorb Cu and Cr metal by using several variations, namely variations in the temperature of the adsorbent activation, adsorbent weight, pH, and contact time, and knowing the kinetic model by determining the reaction order. The results obtained from the characterization of green mussel shells contain elements of Ca, about 67.56% at an activation temperature of 500 °C and 67.34% at an activation temperature of 900 °C. The optimum conditions for Cu metal adsorption by green shell adsorbent were obtained at an activation temperature of 500 °C, using an adsorbent of 1 gram under pH 10 and a contact time of 40 minutes. Whereas for Cr metal absorption, the activation temperature was 900 °C, the mass used was 1.5 grams with pH 7 and the contact time was 40 minutes. The adsorption kinetics model of green mussel shells adsorbent on Cu and Cr metals followed pseudo-second-order

Validasi Metode Analisis Multiresidu Pestisida Organoklor dalam Salak Menggunakan Kromatografi Gas-Detektor Penangkap Elektron

Validation of methods is a key step in the accreditation process of the method. Validation of organoklor pesticide residues method in snakefruit based on the method recommended by FAO-WHO, conducted in LPPT-UGM reported in this study. Snake fruit was homogenized, extracted using toluene/2-propanol (2:1), cleaned up using activated carbon and Celite 545, followed by analysis using gas chromatography-electron capture detector. Validation covered specificity and selectivity, limits of detection and quantification, linear range, precision and accuracy. Validation results showed good specificity and selectivity shown by the inter-peak chromatogram resolution greater than 1.5. Limits of detection and quantification for heptaklor, endosulfan, dieldrin and p, p-DDT were 0.002 and 0.006, 0.5 and 1.7; 0.0006 and 0.002, as well as 0.014 and 0.047 ppm respectively. The linear range for heptaklor, endosulfan, dieldrin, and p,p-DDT were 0.0017 to 2 ppm, 0.165 to 2 ppm, 0.023 to 2 ppm and 0.229 to 2 ppm, respectively. Precision methods meet the acceptance of Horwitz RSD value less than 12.78% at a concentration of 0.3 ppm. Accuracy is indicated by recovery, for each pesticide in the range of 80-110% acceptance at a concentration of 0.1 ppm. Analysis of organochlorine pesticides in three commercial snakefruit samples showed no pesticide residues at concentrations higher than the detection limit.ASBTRAKValidasi metode merupakan tahap kunci dalam proses akreditasi suatu metode. Validasi metode uji residu pestisida organoklor dalam salak berdasarkan metode yang direkomendasikan FAO-WHO, di LPPT-UGM dilaporkan pada penelitian ini. Buah salak dihomogenisasi, diekstraksi menggunakan toluen/2-propanol (2:1), clean up menggunakan karbon aktif dan Celite 545, dilanjutkan analisis menggunakan kromatografi gas-detektor penangkap elektron. Validasi mencakup spesifisitas dan selektivitas, batas deteksi dan kuantifikasi, range linier, presisi serta akurasi. Hasil validasi menunjukkan spesifisitas dan selektivitas yang baik ditunjukkan dengan resolusi antar puncak kromatogram lebih besar dari 1,5. Batas deteksi dan batas kuantifikasi untuk heptaklor, endosulfan, dieldrin dan p,p-DDT secara berturut-turut adalah 0,002 dan 0,006; 0,5 dan 1,7; 0,0006 dan 0,002; serta 0,014 dan 0,047 ppm. Range linier untuk heptaklor adalah 0,0017-2 ppm, endosulfan 0,165-2 ppm, dieldrin 0,023-2 ppm dan p,p-DDT 0,229-2 ppm. Presisi metode memenuhi batas keberterimaan Horwitz dengan nilai RSD lebih kecil dari 12,78% pada konsentrasi 0,3 ppm. Akurasi ditunjukkan dengan recovery, untuk tiap pestisida masuk dalam rentang keberterimaan 80-110% pada konsentrasi 0,1 ppm. Analisis pestisida organoklorin pada 3 sampel salak komersial menunjukkan tidak adanya residu pestisida dengan konsentrasi lebih tinggi dari batas deteksi

Characteristic comparison of cornstarch-based bioplastics using kaolin, microcrystalline cellulose and chitosan as fillers

In the study, the basic material for making bioplastics was corn starch with the addition of kaolin, microcrystalline cellulose, and chitosan as filler variations, as well glycerol as a plasticizer. The method used was the blending method. The characterization included the absorption test for water resistance, biodegradation test, tensile and elongation strength test, and functional group analysis using FTIR. Among fillers, the best bioplastic characteristic bioplastic was obtained with filler kaolin with the water absorption value of 88.62%, a tensile strength value of 1.44 x10-3 MPa, and the elongation strength value of 5.04%. Nearly 80% of the material was degraded in 15 days. Spectra of FTIR showed the appearance of some functional groups from starch, filler, and plasticizer, which meant that the process of bioplastic manufacturing was physical mixing

Effect of Chemical Compounds in Wastes from Essential Oil Distillation on the Activity of E.coli

Effect of chemical compounds in the wastes of essential oil distillation including lime leaves, lemongrass leaves, ylang-ylang flower, and coriander seed on the activity of Escherichia coli has been performed. In this research, observation was done by using microbial fuel cell (using E.coli) with two compartments were connected by nafion membrane and zinc plats were used as electrodes which were connected by copper wire and multimeter. Energy production from the cell was shown from the generated current due to the E.coli's oxidation activity to the substrates (distillation wastes). Results from the research exhibited that chemical compounds in the lime leaves positively affected to the bacterial activity with the generated current present up to 20 µA. It is also observed that mass variation of the substrates significantly affected the current generation. Chemical compounds in the three other wastes were found to be not as effective as lime leaves because from the analysis of their methanol extracts by GC-MS indicated that these contained antibacterial compounds such as octadecanoic acid and rosifoliol. Conclusion from the research was not all of wastes from essential oil distillation have a potency to be used as substrates in the microbial fuel cell as some of these chemicals had an antibacterial property which negatively affected the E.coli bacterial activity in the cell.   Keywords : microbial fuel cell, Escherichia coli, waste of essential oil distillation

INVESTIGATION OF ALTERNATIVE CHEMICAL OXIDATION METHODS FOR COD DETERMINATION AVOIDING DICHROMATE AND MERCURY

In chemical oxygen demand (COD) determination, according to the standard methods, K2Cr2O7 is used as an oxidant and Hg is used in order to inhibit interference of Cl-. K2Cr2O7 and Hg are characterized as toxic substances. In this study, Na2S2O8 and Mn(III) were used as oxidants and in order to inhibit Cl- interference, precipitation using Ag2SO4, removal using anion exchanger and oxidation using bismuthate were investigated. As reference substances for the COD method development, potassium hydrogen phthalate (PHP), glycine, glutamic acid, L-cystein, sodium acetate, and cellulose were used. Oxidation was conducted in the open and closed reflux system followed by COD determination using spectrophotometry or titrimetry. The results showed that precipitation with Ag2SO4 and oxidation with bismuthate could basically be applied in order to inhibit up to a concentration of 1000 mg Cl-/L. Anion exchanger as an alternative method for Cl- removal and Na2S2O8 as an alternative oxidant were found to be inappropriate for the COD test. Mn(III) was found to work in principle as an alternative oxidant to K2Cr2O7. Efficiency of the oxidation for some samples using Mn(III) was comparable to DIN 38409-41. In case of glycine, Mn(III) gave 103% oxidation recovery which was better than DIN 38409- 41 (34%). Combination between oxidation using Mn (III) and Cl- elimination with bismuthate showed a better oxidation method (average recovery rates for PHP COD of 99%) than with precipitation using Ag2SO4 (average recovery rates for PHP COD of <65%)

Adsorption Study of Methylene Blue and Methyl Orange Using Green Shell (Perna Viridis)

Green shell is generally disposed of and become environmental contaminants. In this study, the green shell was used as material to adsorb dyes residue: methylene blue and methyl oranges. Green shell waste from seafood was prepared by removing the dirt then dried at room temperature. It was followed by roughly crushing before being placed in the furnace at temperatures of 300, 500, 700 and 900 °C. The selected adsorbents were sieved at 200 mesh. The adsorbents were characterized by FTIR and SEM-EDX to evaluate their functional groups and morphology. Furthermore, the adsorption process was evaluated by determining the kinetic adsorption models. The results of the FTIR characterization showed the vibration of Ca(OH)2 bone at a wave number of 3400 cm-1 and morphological analysis by SEM showed a homogeneous surface. Adsorption kinetics results obtained from the variation of time with the initial adsorbate concentration showed the kinetic model of both methylene blue and methyl orange adsorption onto the adsorbent followed a pseudo-second order

Effectiveness of activated carbon magnetic composite from banana peel (Musa acuminata) for recovering iron metal ions

Banana peel (Musa Acuminata) contains cellulose that can be used as a carbon-making material. In this study, the activated carbon from banana peel was modified with magnetite to recover iron metal ions in the solution. The manufacture of carbon from banana peels was done by carbonization at a temperature of 450 °C and activated under alkaline conditions with NaOH. The synthesis of activated carbon magnetite composite used FeCl3 and FeSO4 as precursors. The synthesized material was characterized by TGA, FTIR, XRD, and VSM. The thermal stability of activated carbon has increased after the activation process with NaOH. The magnetite composite has formed with saturation magnetization value (Ms) of 14.06 emu/g which is superparamagnetic material. The acidity of the adsorption system influenced this biosorbent effectiveness for the adsorption of iron metal ions in solution. The most optimal adsorption conditions occurred at a pH 6. The optimal adsorption condition is consistent with the Fe(II) adsorption kinetics model using ACM, namely pseudo-second-order with qe = 10.020 mg g−1. The variations in pH affect the Fe(II) adsorption process with ACM, but the adsorption time did not affect the Fe(II) adsorption process with ACM. The adsorption process of Fe(II) with ACM can run optimally in the range of pH ≥ 6 (base condition). The adsorption process at various pH systems did not affect the structure of the activated carbon magnetite (ACM)

The Implementation of Pyrolisis of Waste Material to Bio-Oil in the KKN Course

Kuliah Kerja Nyata (KKN) is one kind of university contribution to community. Through KKN, student also learn how to apply their knowledge and contribute it to community need. In Universitas Islam Indonesia (UII) there are two kind of KKN which are Reguler and Pembelajaran Pemberdayaan Masyarakat (PPM), which differentiate from the topic used. KKN PPM already has major topic that obtained from village destination need. The problem from KKN PPM is limitation time for student to learn about major topic before socialize to community like in KKN UII 57 unit 310-315 which has pyrolisis method as their major topic. Not all the sudent that include in unit 310-315, which come from different study, understand about pyrolisis. To settle this problem, experimental method was choose as learning method used, which help student understand about pyrolisis in limitation time. The effectiveness of this method was observed by observation, interview and questioner. The result show that expertimental method give good result. The student understand basic concept of pyrolisis process that needed in limitation time, eventhough they did not understand anything about pyrolisis method before