Showing papers by "Karna Wijaya published in 2020"

The Synthesis of SO4/ZrO2 and Zr/CaO Catalysts via Hydrothermal Treatment and Their Application for Conversion of Low-Grade Coconut Oil into Biodiesel

Abstract: SO4/ZrO2 and Zr/CaO catalysts have been successfully synthesized and applied to esterification and transesterification process for conversion of coconut oil into biodiesel SO4/ZrO2 catalyst was synthesized via hydrolysis (sol-gel) of ZrOCl28H2O, followed by hydrothermal process, sulfation in various concentration of (NH4)2SO4, and calcination at various temperatures Likewise with Zr/CaO was synthesized through the hydrothermal process by dispersing Zr4+ ions on CaO Zr4+ was formed by desolvation of ZrOCl28H2O in water, then calcination was applied to determine the highest crystalline phase and total basicity The SO4/ZrO2 catalyst had the highest total acidity and crystallized phase at concentrations of 0,5 M (NH4)2SO4 and calcination temperature of 500 °C The Zr/CaO base catalyst had the highest basicity and a new crystalline phase of CaZrO3 was formed at a concentration of 15 % Zr/CaO and the calcination temperature of 800 °C 05 M SO4/ZrO2-500 effectively reduce coconut oil FFA levels in the esterification process 15 % Zr/CaO-800 catalyst successfully converted coconut oil into biodiesel in the transesterification process The biodiesel produced is predominantly of methyl laurate, methyl myristate and methyl palmitate

Fuel Production from LDPE-based Plastic Waste over Chromium Supported on Sulfated Zirconia

Abstract: The preparation, characterization, and catalytic activity test of sulfated zirconia (SZ) modified with chromium for the hydrocracking of LDPE-based plastic waste have been investigated. SZ was prepared by wet impregnation method using zirconia nanopowder (ZrO 2 ) and H 2 SO 4 solution. SZ was further modified with chromium (0.5, 1.0, and 1.5% wt.%) by refluxing in aqueous solution of Cr(NO 3 ) 3 ·9H 2 O, followed by calcination and reduction processes. The prepared catalysts were characterized by SEM-Mapping and TEM. Hydrocracking of LDPE-based plastic waste was conducted at various temperatures and various catalysts. In addition, the optimum catalyst was repeatedly used for the reaction to demonstrate the stability of the catalyst. Liquid products obtained by hydrocracking were characterized by GCMS. The results showed that the morphology of the prepared catalysts had different sizes and disordered shapes after the addition of sulfate and Cr. The effective temperature for hydrocracking was 250 °C. The highest selectivity to liquid product and gasoline fraction were 40.99 and 93.42 wt.%, respectively, and were obtained over Cr/SZ with 1.0 wt.% Cr. Hydrocracking of plastic waste over the used Cr/SZ catalyst with 1.0 wt.% Cr showed that the Cr/SZ catalyst was stable and reusable up to three repetitions.

Effect of Nickel Concentration in Natural Zeolite asCatalyst in Hydrocracking Process of Used Cooking Oil

Abstract: Zeolites impregnated with Ni were successfully synthesized through wet impregnation using activated natural zeolites (ANZs) and the nickel nitrate hexahydrate (Ni(NO3)2·6H2O) precursor at different concentrations of 1%, 2% and 3% (w/w) (hereafter referred to as ANZ/Ni 1%, ANZ/Ni 2%, and ANZ/Ni 3%). The synthesized products were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), surface area analyzer (SAA), scanning electron microscopy (SEM), total acidity measurements by employing ammonia adsorption and Brunauer-Emmett-Teller (BET) theory. The obtained catalysts were employed in the hydrocracking of waste cooking oils, and the formed products were analyzed through gas chromatography-mass spectrometry (GC-MS). The FTIR results indicated that ANZs impregnated with Ni can increase zeolite acidity. The test results of total acidity revealed that 3% ANZ/Ni catalyst exhibited the maximum total acidity of 3.70 mmol/g. XRD diffractogram confirmed the successful impregnation of Ni into ANZs, which was indicated by the characteristic diffraction peaks appearing at 2θ of 9.75º, 13.41º, 19.56º, 22.25º, 25.61º, 27.66º and 31.91º. SEM analysis indicated that the particle size of zeolite catalysts was non-uniform, but these catalysts exhibited a highly uniform surface after they were activated. Moreover, the ANZ catalysts impregnated with different concentrations of Ni exhibited a highly uniform particle size. The ANZ/Ni 3% catalyst had small uniform particle. The BET results revealed that the ANZ/Ni 2% catalyst exhibited the maximum pore volume and surface area and relatively smaller radii of pores. GC-MS was employed to determine liquid products, and its results showed that the ANZ/Ni 3% catalyst had the maximum amount of liquid products of 18%.

Optimizations of microwave-assisted extraction and transesterification of bio-crude oil from spirulina (Arthrospira platensis)

Abstract: Optimizations of microwave-assisted extraction (MAE) and transesterification of bio-crude oil from spirulina (Arthrospira platensis) were conducted. The bio-crude oil from A. platensis was initially extracted using water as a solvent, centrifugation, dissolved with n-hexane, separation, and continued to evaporation. The optimization for the extraction was conducted with varieties of biomass-to-solvent ratio, extraction temperature, extraction time, and n-hexane contact time, yielding the optimum condition with biomass/solvent 1 : 7, extraction temperature 70 °C, extraction time 15 minutes, and contact time 25 minutes (D70/15-25) 5.56%. The average yield of the bio-crude oil obtained was 4.87%, variation 0.32, standard deviation 0.57, and standard error 0.14. The optimization for transesterification was carried out with variations of bio-crude oil-to-methanol ratio, reaction temperature, and reaction time, yielding the optimum condition with bio-crude oil/methanol 1 : 6, reaction temperature 65 °C, and reaction time 50 minutes (G65/50) 98%. The average yield of the bio-diesel obtained was 88%, variation 50.29, standard deviation 7.09, and standard error 2.68. The cell damage before and after extraction and also conventional heating observed using SEM showed massive damage by this method.

Chemical Modification of Montmorillonite K10 and Its Catalytic Activity

Abstract: Montmorillonite K10 (Mt-K10) was chemically modified using a silica-zirconia mixture and the resulting product was named SZMK. The product had an increased total surface acidity, catalytic activity, porosity, and thermal stability. Ammonia adsorption tests and further verification with FTIR and TGA/DTA showed that the acidity of SZMK was higher (0.16 mmol/g) than that of Mt-K10. Catalytic performance was analyzed on the esterification reaction of lauric acid. Refluxing lauric acid and methanol (molar ratio of 1:20) for 20 h with a 20 % (w/w) catalyst showed that catalytic activity of SZMK is high, i.e. methyl laurate production 98.18% (w/w) was achieved.

Catalytic Synthesis of Diethanolamide Surfactant from Used Cooking Oil

Abstract: The synthesis of diethanolamide surfactant from used cooking oil was systematically studied using modified zeolite as catalyst. The activated zeolite was obtained by dispersing natural zeolite in sulfuric acid (H 2 SO 4 ) solution. Potassium carbonate (K 2 CO 3 ) was loaded into activated zeolite by wet impregnation method. The methyl ester obtained from transesterification reaction of used cooking oil was refluxed with diethanolamine (C 4 H 11 NO) solution over K 2 CO 3 /zeolite catalyst in the production of diethanolamide surfactant. The amidiation reaction over K 2 CO 3 /zeolite effectively produced 92% of diethanolamide surfactant with the highest selectivity of methyl oleate. Diethanolamide surfactant showed stable foam and emulsion with the reduction of surface tension as much as 3.3 dyne/cm.

Preparation of Calcium Oxide/Zeolite Nanocomposite and its Application to Improve the Quality of Patchouli Oil

Abstract: The synthesis of CaO/zeolite nanocomposite as a highly active and effective adsorbent for patchouli oil purification has been developed. This research aims to improve the quality of patchouli oil by synthesizing CaO/zeolite nanocomposites using a solid-state mixing method. The used mass ratios of zeolite:CaO were 0:100, 20:80, 40:60, 60:40, 80:20 and 100:0 (w/w), then nanocomposites with various zeolite-to-CaO ratios were then calcined at various temperature of 300°C, 400°C and 500°C. The zeolite, CaO and nanocomposites were characterized by using the Fourier-transform infrared (FTIR), X-ray fluorescence spectrometer (XRF) and surface area analyzer (SAA). The nanocomposites were then applied to patchouli oil and the assessment results of physical and chemical properties of patchouli oil were determined according to Indonesian National Standard (SNI) 06-2385-2006. After patchouli oil purification using ZECA nanocomposite, the acid number decreased from 5.42 to 0.39 mg KOH/g oil, the patchouli alcohol (PA) content increased from 33.08 to 34.27% and the Fe level decreased from 1.39 to 0.31 ppm.

Conversion of Bioethanol to Diethyl Ether Catalyzed by Sulfuric Acid and Zeolite

Abstract: Ethoxy ethane, or diethyl ether, has been successfully synthesized through the condensation reaction of bioethanol produced from fruit waste fermentation using acid-activated H-Zeolite, H2SO4/H-Zeolite, and H2SO4 as catalysts. Zeolite activation was carried out using the acidification method with 1 M, 2 M, 4 M, and 6 M H2SO4 for 24 hours. Activated zeolites were characterized using infrared spectroscopy, X-ray diffraction, and NaOH titration. The condensation reaction of bioethanol was carried out by catalysis of H2SO4/H-Zeolite with various concentrations of 1 M, 2 M, 4 M, and 6 M and catalyzed by 2 M, 4 M, and 6 M acid-activated H-Zeolite. The condensation reaction process was carried out with a ratio of bioethanol to catalyst of 2:1 (w/w) using the fractional distillation method. Ethoxy ethane resulting from the condensation reaction was characterized using a GC instrument.

QSPR Models for Predicting Critical Micelle Concentration of Gemini Cationic Surfactants Combining Machine-Learning Methods and Molecular Descriptors

Abstract: A data set of 231 diverse gemini cationic surfactants has been developed to correlate the logarithm of critical micelle concentration (cmc) with the molecular structure using a quantitative structure-property relationship (QSPR) methods. The QSPR models were developed using the Online CHEmical Modeling environment (OCHEM). It provides several machine learning methods and molecular descriptors sets as a tool to build QSPR models. Molecular descriptors were calculated by eight different software packages including Dragon v6, OEstate and ALogPS, CDK, ISIDA Fragment, Chemaxon, Inductive Descriptor, SIRMS, and PyDescriptor. A total of 64 QSPR models were generated, and one consensus model developed by using a simple average of 13 top-ranked individual models. Based on the statistical coefficient of QSPR models, a consensus model was the best QSPR models. The model provided the highest R2 = 0.95, q2 = 0.95, RMSE = 0.16 and MAE = 0.11 for training set, and R2 = 0.87, q2 = 0.87, RMSE = 0.35 and MAE = 0.21 for test set. The model was freely available at https://ochem.eu/model/8425670 and can be used for estimation of cmc of new gemini cationic surfactants compound at the early steps of gemini cationic surfactants development.

Physico-Chemical Properties of Nano ZrO2-Pillared Bentonite with Nickel as Supporting Metal

Abstract: Bentonite was modified through intercalation and calcination using a ZrOCl2 pillaring solution. To create nano Ni/ZrO2-bentonite catalyst, ZrO2 pillared bentonite was impregnated using Ni(NO3)2•6H2O precursor first, then followed by calcination and reduction. The physical-chemical properties of the catalyst was characterized by XRD (X-ray Diffractometer), FT-IR (Fourier Transform Infrared), surface acidity with NH3 vapor adsorption method, SAA (Surface Area Analyzer) and TEM (Transmission Electron Microscope). The results of characterization with XRD showed specific peaks for montmorillonite minerals with a monoclinic crystalline type and its chemical composition (Ca)(Al,Mg)6(Si4O10)3(OH)6.nH2O and after pillarization showed a shift in basal spacing d001 to the left (angle 2θ <5°). The typical peak indicating basal spacing d001 shift towards a smaller angle of 2θ was not very apparent after impregnation with nickel metal. Qualitative determination of acidity after adsorption of ammonia showed characteristics at 1404-1635 cm-1 wavenumbers with increasingly sharp spectra indicating increased acidity of the catalyst (Brǿnsted and Lewis acids). Surface area showed a significant increase from 27.385 m2/g to 174.208 m2/g after pillarization and impregnation of nickel metal.

Physico-Chemical Properties of Nickel Promoted Sulfated Zirconia Powder Prepared using Different Procedures

Abstract: In this work, nickel promoted sulfated zirconia (Ni/SZ) as catalyst was prepared by either by reflux (Ni/SZ-R) or hydrothermal Ni impregnation (Ni/SZ-H) routes. The aim of this study was to evaluate the influences of two preparative methods on the physico-chemical properties of prepared catalysts. Both the catalysts were characterized by XRD, FTIR, ammonia adsorption, SEM-EDX, TEM-SAED, AAS and BET. It was found that the presence of sulfate and nickel could enhance the Brønsted and Lewis active acid sites. In relation to the effect of Ni impregnation method, acidity, amount of sulfate and Ni found in Ni/SZ-R were higher than those in Ni/SZ-H. Unfortunately, higher impregnated sulfate and nickel on zirconia support led to a decrease in surface area and pore volume and an increase in crystallite size of grainy aggregated mesoporous nickel promoted sulfated zirconia (Ni/SZ).

Synthesis and Characterization of Diethanolamide (Surfactant) from Cao/Zeolite-Catalysed Used Cooking Oil

Abstract: Synthesis of diethanolamide (surfactant) from CaO/zeolite-catalysed used cooking oil has been conducted. The results showed that the yields of the reactions between methyl esters and diethanolamine with CaO concentration at 3%, 5%, and 7% were 64.47%, 92.91%, and 87.05%, respectively. The characterization showed that the higher surfactant concentration, the greater the capability of decreasing surface tension. The water-surfactant-pertalite system had an emulsion index of 67%. The new liquid mixture system (water-surfactant-pertalite) was observed for 4 days to investigate the emulsion stability. The CMC and HLB values were 1.5 g/L and 10.59, respectively. These results show that surfactant is applicable as a cleaning solution with a good emulsion stability.