Synthesis and application of SBA-15-supported CuO as an efficient catalyst for the oxidative C(sp2)-O coupling reaction

SBA-15-supported CuO was synthesized via wet impregnation of SBA-15 with copper (II) acetylacetonate followed by calcination in the static air. The BET surface area of the Cu-containing SBA-15 was approximately 600 m2/g, which significantly decreased in comparison with that of as-synthesized SBA-15 silica (1081 m2/g). The successful loading of copper with a 3.20 wt.% content was determined by ICP-OES analysis, consistent with theoretical composition. However, no Cu-based phases were detected on the PXRD results and TEM images for CuO/SBA-15 showed regular hexagonal meso channels remained, indicating that CuO species was well distributed in the SBA-15 framework via the applied synthetic procedure. Catalytic activity of SBA-15-supported CuO was investigated for the selective C(sp2)-O coupling reaction between salicylaldehyde and N, N-dimethylformamide (DMF) in the presence of di-tert butyl peroxide (DTBP) as an oxidant. Influence of the reaction conditions on the formation of desired product was studied including reaction time, temperature, reactant ratio, amount of catalyst and oxidant. The experimental results proved that the high activity of the prepared catalyst as the C(sp2)-O coupling product could be obtained in an excellent yield of 90% with only 3 mol% of SBA-15-supported CuO in the presence of 4 equivalents of DTBP at 120 °C in 2 hours.

Synthesis of Zinc Fluoroborate by Wet Method and Its Application as a Flame Retardant for Cotton Fabrics

In this study, zinc fluoroborate was synthesized by wet method using fluoroboric acid and zinc oxide as reactant and its usability as flame retardant for cotton fabrics was investigated. The wet method is economical, green, efficient and applicable for a large-scale. The maximum yield was determined related to the variation of reactant ratio, temperature, reaction period and stirrer rate. The characterization of the product was carried out by means of FTIR, BF4- ion selective electrode and XRD. The maximum yield of 97% was achieved at the reactant mole ratio (nZnO/nHBF4) of 1:3, temperature of 90 °C and reaction period of 90 minutes. The purity of the synthesized product was found as 98 %. Flame retardancy and high temperature resistance effects of zinc fluoroborate on cotton fabrics were investigated by LOI test and high temperature durability test method, respectively. Although LOI value of the untreated original fabric was determined as 16, this value increased above 55 by impregnating of fabric with 50 % zinc fluoroborate solution.

Ruminant-Waste Protein Hydrolysates and Their Derivatives as a Bio-Flocculant for Oil Sands Tailing Management

Reclamation of tailings ponds is a critical issue for the oil industry. After years of consolidation, the slurry in tailings ponds, also known as fluid fine tailings, is mainly comprised of residual bitumen, water, and fine clay particles. To reclaim the lands that these ponds occupy, separation of the solid particles from the liquid phase is necessary to facilitate water removal and recycling. Traditionally, synthetic polymers have been used as flocculants to facilitate this process, but they can have negative environmental consequences. The use of biological polymers may provide a more environmentally friendly approach to flocculation, and eventual soil remediation, due to their natural biodegradability. Peptides derived from specified risk materials (SRM), a proteinaceous waste stream derived from the rendering industry, were investigated to assess their viability for this application. While these peptides could achieve >50% settling within 3 h in bench-scale settling tests using kaolinite tailings, crosslinking peptides with glutaraldehyde greatly improved their flocculation performance, leading to a >50% settling in only 10 min. Settling experiments using materials obtained through different reactant ratios during crosslinking identified a local optimum molar reactant ratio of 1:32 (peptide amino groups to glutaraldehyde aldehyde groups), resulting in 81.6% settling after 48 h. Taken together, these data highlight the novelty of crosslinking waste-derived peptides with glutaraldehyde to generate a value-added bioflocculant with potential for tailings ponds consolidation.

Kinetika Pembentukan Struvite Kristal Menggunakan Zeolit Alam sebagai Adsorben pada Aeration Cone Column Crystallizer

Wastewater from the fertilizer industry contains a high concentration of PO43- and NH4+. Those ions formed deposits that frequently clogged the conduits and reduced the pump efficiency of the wastewater treatment plant. A high concentration of PO43- and NH4+ in this wastewater can be used as a secondary source of PO43- fertilizer through the recovery process into struvite compounds (MgNH4PO4.6H2O). In this research, Struvite was crystallized in Aeration Cone Column Crystallizer (ACCC) with Magnesium modified natural Zeolite (Zeo-Mg) as adsorbent. Research also has been done using the Batch process, and the results were used as basis variables in the ACCC system. Effects of Zeolite activation, amounts of Zeo-Mg (10 – 30 g), PO43- and NH4+reactant ratio (1:1 – 1:3), pH (6 – 9), and reaction time (0 – 60 minutes) to the removal percentage of PO43- were used as research parameters that analyzed in struvite crystallization process. Zeo-Mg and struvite produced were analyzed using scanning electron microscopy and energy dispersive X-ray spectroscopy. Research results in the ACCC system with Zeo-Mg as adsorbent showed that the percentage of PO43- removal was 65% in 16 minutes and followed pseudo-first-order reaction kinetics with a reaction rate constant of 0.21 min-1. The PO43- removal reached equilibrium at pH 8.10 after 28 minutes. Simultaneous removal of PO43- to formed struvite crystals using Zeo-Mg as an adsorbent and without the addition of Mg ions solution in the ACCC system is a novel process in wastewater treatment. Moreover, this PO43- recovery process can be implemented in the industrial scale due to the practical operation.A B S T R A KAir limbah industri pupuk banyak mengandung PO43- dan NH4+. Ion-ion ini membentuk endapan yang seringkali menyumbat aliran pipa yang menyebabkan penurunan efisiensi pompa di instalasi pengolahan air limbah. Kandungan PO43- dan NH4+ berkonsentrasi tinggi ini dapat dijadikan sumber sekunder untuk membuat pupuk PO43- dengan melakukan recovery sebagai senyawa struvite (MgNH4PO4.6H2O). Pada penelitian ini, struvite dibentuk menjadi kristal menggunakan Aeration Cone Column Crystallizer (ACCC) dengan adsorben zeolit alam yang telah dimodifikasi menggunakan ion magnesium (Zeo-Mg). Penelitian juga dilakukan dengan menggunakan proses batch, yang hasilnya dijadikan basis variabel pada sistem ACCC. Pengaruh pengaktifan zeolit, penambahan Zeo-Mg (10–30 g), rasio reaktan PO43- dan NH4+ (1:1–1:3), perubahan pH larutan (6–9), dan lamanya waktu reaksi (0–60) menit terhadap persentase penyisihan PO43- menjadi parameter yang dianalisis pada proses kristalisasi struvite. Zeo-Mg dan struvite yang dihasilkan dianalisis menggunakan scanning electron microscopy dan energy dispersive X-ray spectroscopy. Penelitian menggunakan ACCC menghasilkan persentase penyisihan PO43- dengan adsorben Zeo-Mg sebesar 65% dalam 16 menit dan mengikuti persamaan kinetika reaksi orde satu, dengan konstanta laju reaksi 0,21 min-1. Penyisihan PO43- mencapai kesetimbangan pada pH 8,10 setelah 28 menit. Proses pemisahan PO43- dengan adsorben Zeo-Mg menjadi struvite secara berkesinambungan pada sistem ACCC merupakan proses baru pengolahan air limbah. Selain itu, proses pemanfaatan kembali PO43- ini dapat diterapkan ke dalam skala industri karena kemudahan dalam pengoperasiannya.

Kinetic Analysis of 4-Nitrophenol Reduction by “Water-Soluble” Palladium Nanoparticles

The most important model catalytic reaction to test the catalytic activity of metal nanoparticles is the reduction of 4-nitrophenol to 4-aminophenol by sodium borohydride as it can be precisely monitored by UV–vis spectroscopy with high accuracy. This work presents the catalytic reduction of 4-nitrophenol (4-Nip) to 4-aminophenol (4-Amp) in the presence of Pd nanoparticles and sodium borohydride as reductants in water. We first evaluate the kinetics using classical pseudo first-order kinetics. We report the effects of different initial 4-Nip and NaBH4 concentrations, reaction temperatures, and mass of Pd nanoparticles used for catalytic reduction. The thermodynamic parameters (activation energy, enthalpy, and entropy) were also determined. Results show that the kinetics are highly dependent on the reactant ratio and that pseudo first-order simplification is not always fit to describe the kinetics of the reaction. Assuming that all steps of this reaction proceed only on the surface of Pd nanoparticles, we applied a Langmuir−Hinshelwood model to describe the kinetics of the reaction. Experimental data of the decay rate of 4-nitrophenol were successfully fitted to the theoretical values obtained from the Langmuir–Hinshelwood model and all thermodynamic parameters, the true rate constant k, as well as the adsorption constants of 4-Nip, and BH4− (K4-Nip and KBH4−) were determined for each temperature.

Synthesis of cymene in flow reactor over rare earth metal modified zeolite catalyst

In the present investigation transalkylation of cumene with toluene was carried over a series of zeolite containing rare earth metals such as lanthanum (La), cerium (Ce), and praseodymium (Pr). The modified zeolites were further characterized by EDS, XRD, BET and TPD. The surface area and acidities of the modified zeolite catalysts were reported. The transalkylation reactions were carried out varying different parameters such as metal loading (2–10 wt%), temperature (448–573 K), reactant ratio (1–15), and space-time (3.2–9.29 kg h/kmol). Praseodymium-modified X zeolite (PrX) showed the highest cumene conversion (60 wt%) and cymene selectivity (65.7 wt%) compared to the other zeolites. The maximum cumene conversion and cymene selectivity were obtained at 523 K, the toluene-to-cumene ratio of 9:1, and space-time of 9.29 kg h/kmol. Mass transfer resistances were studied in the said reaction conditions.

Processing Fish Waste Into Biodiesel Using Microwave Radiation

The fish waste contains a lot of oil, so there needs to be a way to treat fish waste to be more useful. One way that can be done is to process it into biodiesel. Biodiesel production begins with taking oil from fish waste by steaming, fish waste oil was analyzed for free fatty acid levels, and obtained by 1.8%. The process was continued with esterification because the FFA value was above 1%, with a reaction time of 15 minutes and a 450watt microwave power. The esterification and transesterification process were carried out in a modified microwave. This study uses a variable change in the form of micro-wave (microwave) power variations of 300, 450, 600 and 800 watts and the ratio of moles of oil to methanol 1: 6, 1:12, 1:18, 1:24. The highest yield obtained by Biodiesel in reactant ratio 1:18 variable and 600 watt microwave power by 97%, while the lowest yield in variable 1: 6 with 300 watt microwave wave power by 88%. Biodiesel from fish waste produced was analyzed using GC-MS to determine the formation of methyl esters. The methyl esters contained in the form of stearic acid with an area of 21%. Analysis of the characteristics of biodiesel density was 863 kg/m3, viscosity was 3.12 mm2/s, cetane number was 55.72. From several characteristics test of biodiesel, fish waste is included in the biodiesel requirements of the Indonesian National Standard. Testing the water content is still high above the limit set by SNI biodiesel which is equal to 0.80%.

PLANT OIL VALORIZATION BY CROSS-METATHESIS REACTIONS: SYNTHESIS OF FINE CHEMICALS FROM METHYL OLEATE

This work studies the production of high-value compounds by the cross-metathesis of methyl oleate (MO) with ethylene, cinnamonitrile and cinnamaldehyde using the 2nd generation Hoveyda-Grubbs complex (HG) as catalyst, either dissolved in toluene or supported on silica. Reactions were carried out in batch reactors between 313 and 343 K. The yield to cross-metathesis products (YC-M) for the MO cross-metathesis with cinnamonitrile and cinnamaldehyde increased with the initial molar reactant ratio (RCN/MO, RCA/MO), reaching YC-M values of 82% and 95%, respectively, at R = 7. No catalyst deactivation took place during the 400-min catalytic runs. The liquid-phase cross-metathesis of MO with ethylene (ethenolysis) was performed over HG(10%)/SiO2 catalysts, producing 1-decene and methyl 9-decenoate, a valuable intermediate for the synthesis of pheromones. At RC2/MO = 2.5, the selectivity to ethenolysis products was 77% at 82% MO conversion. The MO self-metathesis was the only side reaction observed in all the catalytic tests.

The Use of Natural Zeolite as A Catalyst for Esterification Reaction Between Glycerol and Oleic Acid

Natural zeolite in Indonesia generally divided into 2 types, which are mordernite and clinoptilolite. As far the use of zeolites is very limited. This experiment tries to use both types of natural zeolites to find out its work. The purpose of this experiment is testing the performance of mordenite natural zeolite from Bayah-Indonesia and clinoptilolite from Lampung- Indonesia in the esterification reaction between glycerol and oleic acid integrated by several variable that affect the reaction. The experiment will be done by using three-neck rounded flask batch reactor. The result showed that modernite zeolite has a better performance compared to clinoptilolite zeolite. To get the oleic acid conversion of 70%, clinoptilolite zeolite needs 4% catalyst of glycerol weight and reactant ratio of 6:1 mole of glycerol/mole of oleic acid, Meanwhile the mordernite zeolite only needs 2% catalyst of glycerol weight with reactant ratio of 4:1 mole of glycerol/mole of oleic acid.Keywords: natural zeolite; glycerol; reaction; diffusion