Renewable Heterogeneous Catalyst Research Articles

Biodiesel Synthesis from Coconut Oil Using the Ash of Citrus limetta Peels as a Renewable Heterogeneous Catalyst

Biodiesel Synthesis from Coconut Oil Using the Ash of Citrus limetta Peels as a Renewable Heterogeneous Catalyst

La‐Doped Mg‐Al Composite Oxides: Efficient Catalysts for the synthesis of Diethyl Carbonate via Transesterification of Ethylene Carbonate with Ethanol

AbstractSeries of La‐doped Mg−Al composite oxides were prepared by co‐precipitation method and used as catalysts for the synthesis of diethyl carbonate (DEC) via transesterification of ethylene carbonate (EC) with ethanol (EtOH). SEM, XRD, FT‐IR and XPS results confirmed that the introduction of La enhanced the interaction with MgO. The 8 mol % La‐doped Mg−Al composite oxide (calcined catalyst named HTC‐0.8 La) produced strong interactions and improved lattice oxygen content (27.84 %). Based on the N2 adsorption‐desorption and CO2‐TPD results, the HTC‐0.8 La catalysts possessed abundant multistage mesoporous structure, high strong base density and strength (0.941 mmol ⋅ g−1). Therefore, the HTC‐0.8La catalyst exhibited high catalytic activity with 58.5 % yield of DEC and 94.7 % selectivity to DEC (EC: EtOH molar ratio=1 : 6, reaction time=1.5 h, reaction temperature=150 °C and catalyst amount=3.2 wt %). Based on the correlation between catalytic activity and alkalinity, the yield of DEC was positively and linearly related to the strong alkali density of the catalyst. After five replicate experiments, the DEC yield after recovery and roasting reached 54.1 %, indicating that HTC‐0.8La is a renewable heterogeneous catalyst.

An effective green and renewable heterogeneous catalyst derived from the fusion of bi‐component biowaste materials for the optimized transesterification of linseed oil methyl ester

AbstractBiological waste materials are rich sources of important minerals such as calcium and potassium, which are required in the preparation of effective biocatalysts for biodiesel production. Their adoption into green catalyst production is becoming important due to the ease of process synthesis and the availability of waste animal shells and agricultural materials. In this study, the potential of a bi‐component, heterogeneous catalyst of fused chicken eggshells and pawpaw peels was tested in the transesterification reaction of linseed oil. The waste materials, separately, were dried and calcined at 900 °C or at 700 °C for 3 h to obtain their calcined ashes (calcined eggshells (CES) and calcined pawpaw peels (CPP)). The CES and CPP were then bonded by the wet impregnation method (by dissolving each ash at weight concentration of 7:3 CES/CPP in 100 mL warm distilled water and further calcining them at 600 °C for 2 h). The catalyst that was developed was characterized using Scanning Electron Microscopy ‐ Energy Dispersive X‐Ray Spectroscopy (SEM–EDX), X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The Box–Behnken design was applied to generate 15 experimental runs, which were used to investigate the effect of the operational parameters such as methanol‐to‐oil molar ratio, catalyst loading, and reaction time. The characterization results show that the ash is very rich in Ca and K ions. The best reaction condition for the transesterification process was found to be a methanol / oil molar ratio of 14.9:1, catalyst loading of 3.78 wt%, process reaction time of 80 min at constant reaction temperature of 65 °C with a biodiesel maximum yield of 91.20 wt%. The physicochemical properties of the produced biodiesel were measured and found to meet the American Society for Testing of Materials (ASTM) and European National (EN) standards and South African National Standards (SANS) biodiesel quality standards. The fused catalyst can be reused for up to five cycles with little reduction in yields. The study demonstrates the potential of utilizing biomass feedstock in developing effective and sustainable biodiesel fuels. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

Valorization of banana pseudostem as a catalyst for transesterification process and its optimization studies

Concerns over the diminution of conventional fossil fuels have insisted on the development of alternative renewable sources such as biodiesel due to its sustainability, and minimal carbon emission characteristics. The present study discusses the production of Madhuca indica methyl esters (MIME) utilizing eco-friendly, renewable heterogeneous catalyst synthesized from the Poovan banana pseudostem (PBPS). Madhuca indica oil (MIO) used in the current study holds a high acid value of 21.7 ± 0.02 mg of KOH/g of oil. The acid-catalyzed esterification was performed followed by heterogeneous base–catalyzed transesterification process to reduce the acid value. The developed catalyst was characterized by energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) analysis. Furthermore, the transesterification parameters, i.e., catalyst loading, reaction time, and methanol to oil molar ratio, were investigated by performing seventeen predesigned experimental runs using response surface methodology (RSM) which determines the effect of the independent variables on the conversion of MIO to MIME. Numerical optimization tool revealed that the maximum conversion of 98.8% is accomplished at optimal reaction conditions of 5.9 wt% catalyst, 14.9 of methanol to oil molar ratio with the reaction time of 178.1 min. The outcome of this research supports that the indigenous catalyst developed via calcination of PBPS can be utilized as an environmentally benign and highly efficient solid catalyst for synthesis of biodiesel.

Cobalt-doped CaO catalyst synthesized and applied for algal biodiesel production

Microalgal biomass is a potential feedstock for biofuel production because of its oleaginous nature and fast growth rate. Furthermore, its cultivation does not compete with crop producing land and thereby eliminating food vs. fuel dilemma. This study describes a low-cost nutrient mediated cultivation method for growing lipid enriched algal biomass from Scenedesmus quadricauda in BG11 media in a raceway pond. A renewable heterogeneous catalyst is synthesized using calcium oxide obtained from calcination of waste egg shells and modified using cobalt nitrate hexahydrate by co-precipitation method. The synthesized catalyst is characterized by XRD, SEM, EDX, FTIR, TEM techniques. Lipid extracted from the biomass is converted to biodiesel using the synthesized catalyst. The formation of biodiesel is confirmed using 1 H NMR, 13C NMR and GC-MS techniques. The result demonstrated that the CaO–Co catalyst has very high catalytic activity for biodiesel production. The integrated process described in this study has potential for producing environmentally benign fuels and a heterogeneous catalyst from renewable sources. • The microalgae Scenedesmus quadriacuda is a good candidate for biofuel production. • KNO 3 helps in lipid enhancement. • The catalyst CaO-Co is renewable in nature. • The algal biodiesel yield is 98%.

Biodiesel production over a catalyst prepared from biomass-derived waste date pits

Date palms are predominately produced in arid regions and the date pits, or seeds, produced from them are sometimes considered to be a waste. Date pits, ground to powder following an oil extraction, were used to synthesize a renewable heterogeneous catalyst. The green carbon catalyst was modified by an alkaline earth metal oxide (CaO). The oil extracted from date pits was transformed into biodiesel. The biodiesel process was optimized and the optimal yield was 98.2 wt% at a reaction temperature of 70 °C, reaction time ∼120 min, methanol to oil molar ratio of 12 and catalyst loading of 4.5 wt%. The quality of the produced biodiesel meets the standard limits set by regulating agencies (ASTM, EU) which indicates its suitability to be used as a fuel. Thus, it can be concluded that the green carbon catalyst synthesized from waste date pits has a high potential for biodiesel production.

Advancement in the Utilization of Biomass-Derived Heterogeneous Catalysts in Biodiesel Production

Solid oxide catalysts derived from various renewable sources have produced significant yield of methyl esters of enhanced purity. These materials are sourced for due to their advantages ranging from low cost, recoverability and reusability, environmental benign-ness, thermal stability and high quality product generation. For a possible greener production process, many researchers in literature reported the use of biomass-derived heterogeneous catalyst in biodiesel synthesis producing high quality pure product. The catalysts were majorly modified through simple physical cost effective and energy saving operations. This paper explores some of these bio-based heterogeneous catalyst used in biodiesel production via transesterification and esterification approach and their performance in FAME yield and conversion. The feedstock consideration which warrant the route selection, various approaches that are adopted in biodiesel production, performance of renewable heterogeneous catalyst and the measures that were adopted to enhance efficiency of the catalyst were considerably highlighted. It is observed that the prospects of organic-based solid catalyst in biodiesel development is a promising enterprise compared to the conventional methods utilizing homogeneous chemical catalyst, which generates wastewater requiring treatment before disposal and generates product that may cause engine malfunction. This review work aimed at providing detailed and up-to-date record of the trend in renewable catalyst development in biodiesel synthesis. This is expected to inform a suitable selection and reaction conditions in the development of biodiesel from the very many feed stocks.

Musa balbisiana Colla peel as highly effective renewable heterogeneous base catalyst for biodiesel production

Biodiesel production process encourages use of heterogeneous catalyst over homogeneous catalysts. The major problems associated with the use of homogeneous catalysts are its non-renewable nature, separation and washing which can be overcome by the use of heterogeneous catalysts. Therefore, in this work use of Musa balbisiana Colla peels, a waste biomass material has been used for preparing eco-friendly and highly effective heterogeneous base catalyst for sustainable biodiesel production. The peels of Musa balbisiana Colla have been characterized by Fourier transform infrared spectroscopy (FTIR), powder X-ray diffractograms (XRD), Energy Dispersive Analysis of X-ray (EDAX), Brunauer–Emmett–Teller (BET), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) analysis. The conversion of the waste cooking oil into biodiesel was confirmed by proton nuclear magnetic resonance (1H NMR), Carbon-13 nuclear magnetic resonance (13C NMR) and Gas Chromatography-Mass Spectroscopy (GC–MS) techniques. The peels of Musa balbisiana Colla furnished 100% conversion of waste cooking oil into biodiesel. Low cost, renewable heterogeneous catalyst from banana (Musa balbisiana Colla) peels can be developed for fatty acid methyl esters (FAME) production providing a new route for sustainability of fuels.

Synthesis, characterization and structural study of a phosphonium salt containing the [Pd2Br6]2− ion and its application as a novel, efficient and renewable heterogeneous catalyst for amination of aryl halides and the Stille cross-coupling reaction

In this study palladium(II) acetate reacts with a phosphonium salt, [Ph3PCH2C6H4CH2Br]Br, to give [Ph3PCH2C6H4CH2OC(O)CH3]2[Pd2Br6]. Characterization of the obtained compound was performed by elemental analysis, IR, 1H, 31P, 13C NMR and X-ray crystallography. It was found that this compound can act as an efficient catalyst for amination of aryl halides to afford primary amines and satisfactory results were obtained. It has also been successfully employed in the catalytic Stille cross-coupling reaction. The catalyst is easily recoverable and reusable without significant loss of its catalytic activity.

Chitosan: an efficient promoter for the synthesis of 2-aminopyrimidine-5-carbonitrile derivatives in solvent free conditions

Reusable chitosan without any post-modification, with active –NH2 and –OH groups, was found to be a highly efficient and renewable heterogeneous catalyst for the rapid and convenient synthesis of 2-aminopyrimidine-5-carbonitrile derivatives from guanidines, aldehydes and cyanoketones, under mild reaction conditions at 85 °C in good yields. Undoubtedly this methodology gives a facile and straightforward pathway to construct 2-aminopyrimidine-5-carbonitrile derivatives in an eco-friendly fashion.

Chitosan as a Renewable Heterogeneous Catalyst for the Knoevenagel Reaction in Ionic Liquid as Green Solvent

The combination of chitosan as a renewable heterogeneous catalyst and ionic liquid as a “green” solvent was employed for the Knoevenagel reaction. The chitosan catalyst was characterized by various techniques, including X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), and elemental analysis. Excellent conversions were achieved under mild conditions without the need for an inert atmosphere. There was no contribution from leached active species, and conversion was only being possible in the presence of the solid catalyst. The chitosan catalyst as well as the ionic liquid solvent could be recovered in essentially pure form after being used in the reaction, and each of them could be reused several times without a significant degradation in efficiency.

Fe(III)-Immobilized Collagen Fiber: A Renewable Heterogeneous Catalyst for the Photoassisted Decomposition of Orange II

A novel catalyst for the Fenton reaction was prepared by immobilizing Fe(III) onto collagen fiber, and its catalytic activity for the photoassisted decomposition of Orange II was investigated. The results indicated that this catalyst, Fe(III)-immobilized collagen fiber (FICF), follows an adsorption−decomposition mechanism so that it can effectively accelerate the decoloration and mineralization rates of Orange II in aqueous solution. Catalyzed by FICF (0.5 g/L, 91 mg/g Fe loading), the TOC of Orange II solution (1000 mL, 0.2 mM, pH 6.42) was 62.9% removed within 90 min under UVC irradiation (254 nm, 10 W) in the presence of H2O2 (5.0 mM); meanwhile, the dye solution was completely decolorized. FICF can be recycled 10 times with little activity loss, and its catalytic activity can be easily recovered by reimmobilization of Fe(III). Therefore, FICF could act as an efficient and cost-effective catalyst for the photoassisted decomposition of Orange II.