Sintesis Tris(4-metoksifenil)tolilsilan Dengan Teknik Reaksi Kopling Menggunakan Katalis Paladium Tersier Tributil Fosfin

Telah disintesis senyawa tris(4-metoksifenil)tolilsilan (TMT) dengan teknik reaksi kopling menggunakan tolilsilan dan 4-iodida anisol yang dikatalis senyawa paladium. Reaksi dilakukan dalam kondisi inert dan suasana basa. Senyawa TMT hasil sintesis dikarakterisasi menggunakan kromatografi gas-spektrometri massa dan spektrometer 1H dan 13C NMR. Hasil penelitian menunjukkan bahwa senyawa TMT hasil sintesis memiliki rendemen sebesar 30%. Pengukuran menggunakan kromatografi gas-spektrometri massa menghasilkan nilai m/z sebesar 440. Spektrum 1H NMR menunjukkan lima puncak proton ekivalen dan spektrum 13C NMR menghasilkan sepuluh puncak karbon ekivalen. Hasil karakterisasi tersebut bersesuaian dengan struktur senyawa TMT hasil sintesis

TiO2/Kaolin composite as low-cost adsorbent for procion red removal from aqueous solution: kinetics, equilibrium, and thermodynamic studies

ABSTRACT. Procion red is one of the most utilized textile dyes by numerous textile factories worldwide. Unfortunately, it has a detrimental effect on the ecosystem whenever it was released into the environment as textile wastewater. In this work, the removal of procion red from aqueous solution has been conducted by adsorption with modified natural kaolin as a low-cost adsorbent. Kaolin was systematically modified by thermal activation then followed by acid activation in different acid concentration. Activated kaolin sample was then mixed with TiO2 to produce TiO2/Kaolin composite. Activated kaolin and TiO2/Kaolin composite were characterized using X-ray diffraction (XRD) and Fourier transform infrared (FT-IR). Various operational variables that affect the adsorption process were taken into consideration, including the effect of initial pH, contact time, initial dye concentration, and temperature. The adsorption parameters of kinetics, isotherm, and thermodynamics were also studied according to the most common model established. The results showed that the procion red adsorption was pH-dependent and reached equilibrium at 90 min. The kinetics study was revealed that the adsorption process was better demonstrated by the pseudo-first-order rather than the pseudo-second-order model. The adsorption isotherm investigation showed that the adsorption process was followed both Langmuir and Freundlich model with qe reached 158 mg/g, and the adsorption process was predicted in favorable condition. The thermodynamic study revealed that the adsorption process is spontaneous with endothermic nature. According to the results, it can be considered that the TiO2/Kaolin composite adsorbent has better adsorption capability to the procion red.               KEY WORDS: Activated kaolin, TiO2, Composite, Adsorption, Procion red Bull. Chem. Soc. Ethiop. 2019, 33(3), 437-450.DOI: https://dx.doi.org/10.4314/bcse.v33i3.

Study Adsorption Desorption of Manganese(ii) Using Impregnated Chitin-cellulose as Adsorbent

- Study adsorption desorption of manganese(II) using impregnated chitin-cellulose as adsorbent has been carried out. Chitin was extracted from snail shell and cellulose isolated from rice straw. Chitin and cellulose were impregnated using thiourea as impregnant agent. Characterization of chitin and cellulose was performed using FTIR spectroscopy, determination of water content, and ash content, while impregnated chitin-cellulose was characterized using FTIR spectrophotometer and X-Ray diffractometer. The adsorption of Mn(II) on impregnated chitin-cellulose was studied through determination of adsorption time and the influence of Mn(II) concentration, while desorption was carried out sequentially using various reagents. The results shown that chitin and cellulose from extraction processes are has similar FTIR spectrum compared to chitin and cellulose standard. The FTIR spectrum of impregnated chitin-cellulose shows both vibration of chitin and cellulose appeared and indicated successfully impregnate. These results were also equal to XRD pattern analysis. The water and ash contents of chitin are 0.038% and 0.043 while for cellulose are 0.184% and 0.165%, respectively. The adsorption of Mn(II) on chitin and cellulose are quite similar kinetically, while adsorption of Mn(II) on impregnated chitin-cellulose is higher at the same time with chitin and cellulose. In the low concentration of Mn(II), adsorption phenomena are similar on chitin, cellulose, and impregnated chitin-cellulose. Desorption process of Mn(II) on the adsorbents shows sodium etilenediamine tetra acetate able to desorp Mn(II) up to 68% higher than other reagents

Komposisi, Kekayaan, dan Kelimpahan Plankton di Perairan Sungai Simpang Heran dan Sungai Sugihan sebagai Instrumen Bioindikator Lingkungan Hidup

The Simpang Heran dand Sugihan rivers has been planned for outlet factory by the OKI Pulp and Paper. The changing function of these areas give some effects to quality of water and biota around the river. The aims of this research is to study of plankton structure community as biomonitoring instrument. The re-search was conducted during August 2017. The location sampling was determined by purpossive random sampling method in 3 stations. The sampling in the moody area was carried out by Eckman grab. The results showed that 70 genera have been classified into 9 classes. Plankton abundance ranges from 372 - 408 ind/l highest found in the confluence of Sungai Simpang Heran and Sungai Sugihan. The species diversity index ranges from 3 - 3.08 and, the low dominant index is around 0.03

Calcium Oxide Decomposed From Chicken\u27s and Goat\u27s Bones as Catalyst for Converting Discarded Cooking Oil to Be Biodiesel

Thermal decomposition of calcium oxide from chicken\u27s (Gallus gallus domesticus) and goat\u27s (Capra Hircus Aegragus) bones was prepared at temperature variations of 400, 500, 800, 900, 1000, and 1100 oC respectively. X-ray diffractometer (XRD), FT-IR and SEM were used for calcium oxide characterization. XRD diffraction pattern of the bone\u27s after thermal decomposition at 1100oC has similarity to the XRD standard diffraction pattern from Joint Committee on Powder Diffraction Standard (JCPDS). Diffractions of 2q values being used are 34.2o, 37.3o, 58.3o, 64.1o, and 67.3 o. Ca-O presence in the samples was detected by FT-IR characterization at wavenumber of 354,90 cm-1. SEM profile show reducing size of bones after decomposition in both chicken\u27s and goat\u27s bones. Furthermore, the prepared calcium oxide was applied for biodiesel synthesis from discarded cooking oil through transesterification reaction. By applying the catalysts decomposed from chicken\u27s and goat\u27s bones, the biodiesel product showed characteristics as follows: biodiesel applied the chicken\u27s bone catalyst has fatty acid number of 0.56 mg/KOH, iod number of 22.41 g I2/100 g KOH, density of 0.88 g/cm3 and viscosity of 5.91 mm2/s, while biodiesel applied the goat\u27s bone catalyst has 0.56 mg/KOH, iod number of 21.57 g I2/100 g KOH, density of 0.88 g/cm3 and viscosity of 6.34 mm2/s. Those biodiesel\u27s characteristic values meet the National Standard of Indonesia (SNI) for biodiesel