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Acetylation of glycerol to yield monoacetin (MAT), diacetin (DAT), and triacetin (TAT) over NiO-supported CeO2 (xNiO/CeO2) catalysts is reported. The catalysts were synthesized utilizing a sol-gel technique, whereby different quantities of NiO (x = 9, 27, and 45 wt%) were supported onto the CeO2 substrate, and hexadecyltrimethylammonium bromide (CTABr) served as a porogen. The utilization of EDX elemental mapping analysis confirmed the existence of evenly distributed Ni2+ ion and octahedral NiO nanoparticles on the CeO2 surface through the DRS UV-Vis spectroscopy. The most active catalyst is 27NiO/CeO2 based on TAT selectivity in the glycerol acetylation with ethanoic acid, attaining 97.6% glycerol conversion with 70.5% selectivity to TAT at 170 °C with a 1:10 glycerol/ethanoic acid molar ratio for 30 min using a non-microwave instant heating reactor. The 27NiO/CeO2 is reusable without significant decline in catalytic performance after ten consecutive reaction cycles, indicating high structure stability with accessible active acidity.

Various research showed that antioxidants can effectively overcome the damage caused by free radicals to human health. Therefore, antioxidants are identified as one of the main directions in the development of health care and cosmetics products due to high demand in the market. This review mainly focuses on the phycocyanin, a type of natural antioxidant mainly found in cyanobacteria. This mini review summarizes the phycocyanin sources and numerous extraction methods of phycocyanin along with the analytical methods and determine its ability to suppress free radicals. Phycocyanin has been proven to play an important role in scavenging free radicals and enhancing the body’s antioxidant capacity. However, there is a lack of long-term randomized clinical trial results that can be used as evidence in showing the benefits of phycocyanin. The existing phycocyanin extraction methods using solvents, ultrasonic-assisted, freeze-thaw, etc. can extract high-quality phycocyanin efficiently and quickly. Scientists are also trying to incorporate advanced technologies, such as "Industry 4.0" to optimize and enhance the industrial production of phycocyanin. Lastly, this review also describes the difficulties faced during the phycocyanin production or extraction process and financial obstacles in order to achieve the popularization of phycocyanin.

A detailed investigation of the hydrothermal crystallization of SAPO-34 in the presence of the novel 1-propylpyridinium hydroxide ([PrPy]OH) organic structural directing agent is presented. The synthesis conditions are systematically tuned to investigate the effects of various parameters (viz. concentrations of each reactant, crystallization time, and temperature) on the nucleation and crystallization of SAPO-34. The results show that a careful variation in each of the synthesis parameters results in the formation of competing phases such as SAPO-5, SAPO-35, and SAPO-36. Pure and fully crystalline SAPO-34 can be crystallized using a precursor hydrogel of a molar ratio of 2.0 Al: 4.7 P: 0.9 Si: 6.7 [PrPy]OH: 148 H2O at 200 °C for only 19 h, which is a shorter time than that found in previous studies. The prepared SAPO-34 is also very active in the esterification of levulinic acid and 1-propanol. By using microwave heating, 91.5% conversion with 100% selectivity toward propyl levulinate is achieved within 20 min at 190 °C. Hence, the present study may open a new insight into the optimum synthesis study of other zeolites using novel pyridinium organic moieties and the opportunity of replacing conventional harmful and non-recyclable homogeneous catalysts in levulinate biofuel synthesis.

A study using a novel pyridinium ionic liquid, namely 1-propylpyridinium bromide ([PPy]Br), to crystallize SAPO-11 under ionothermal conditions is reported. By carefully following the crystallization process, SAPO-11 can readily be crystallized in the presence of [PPy]Br, which serves as a synthesis solvent and structure-directing agent, at 150 °C after 133 h of heating. The study also focuses on manipulating other synthesis parameters (e.g., crystallization temperature, phosphorous content, silicon amount and [PPy]Br concentration) and investigating their respective effects on the formation of SAPO-11. The crystallized SAPO-11 has an acidic nature and a high surface area. Under conductive instant heating conditions, the SAPO-11 catalyst is very active in the conversion of levulinic acid into ethyl levulinate; 93.4% conversion and 100% selectivity of ethyl levulinate are recorded at 180 °C after 30 min of reaction. This result is comparable to or even better than those of conventional homogeneous catalysts.

In the context of climate change and the increase of the energy demand, there is a need for carbon sequestration methods and sustainable fuels. This can be done by cultivation of microalgae, an unicellular microscopic algae that converts carbon dioxide into high-value bioproducts and energy. Moreover, microalgae can be used to assess the health of ecosystems such as lakes. Here we review microalgae for biofuel, for wastewater treatment and as bioindicators. We discuss the impact of processes based on microalgae using life cycle assessment. We present co-cultivation of microalgae with other microbes, and we compare conventional processes with processes integrating auto-flocculation, in situ transesterification and excretion.

Downstream processing or product recovery plays a vital role in the development of bioprocesses. To improve the bioprocess efficiency, some unconventional methods are much required. The continuous manufacturing in downstream processing makes the Process Analytical Technologies (PATs) as an important tool. Monitoring and controlling bioprocess are an essential factor for the principles of PAT and quality by design. Spectroscopic methods can apply to monitor multiple analytes in real-time with less sample processing with significant advancements. Raman spectroscopy is an extensively used technique as an analytical and research tool owing to its modest process form, non-destructive, non-invasive optical molecular spectroscopic imaging with computer-based analysis. Generally, its application is essential for the analysis and characterization of biological samples, and it is easy to operate with minimal sample. The innovation on various types of enhanced Raman spectroscopy was designed to enhance the Raman analytical technique. Raman spectroscopy could couple with chemometrics to provide reliable alternative analysis method of downstream process analysis. Thus, this review aims to provide useful insight on the application of Raman spectroscopy for PAT in downstream processing of biotechnology and Raman data analysis in biological fields.

Algal green energy has emerged as an alternative to conventional energy production using fossil fuels. Microbial fuel cells (MFCs), photosynthetic microbial fuel cells (PMFCs) and biophotovoltaic (BPV) platforms have been developed to utilize microalgae for bioelectricity generation, wastewater treatment and biomass production. There remains a lack of research on marine microalgae in these systems, so to the best of our knowledge, all information on their integration in these systems have been gathered in this review, and are used to compare with the interesting studies on freshwater microalgae. The performance of the systems is extremely reliant on the microalgae species and/or microbial community used, the size of the bio-electrochemical cell, and electrode material and distance used. The mean was calculated for each system, PMFC has the highest average maximum power density of 344 mW/m(2), followed by MFC (179 mW/m(2)) and BPV (58.9 mW/m(2)). In addition, the advantages and disadvantages of each system are highlighted. Although all three systems face the issue of low power outputs, the integration of a suitable energy harvester could potentially increase power efficiency and make them applicable for lower power applications.

This study employed the microwave-assisted acid hydrolysis pretreatment using wet torrefaction on two indigenous microalgae, Chlorella vulgaris ESP-31 and Chlorella sp. GD with different biomass composition to investigate the yields of solid biochar and total reducing sugar in the liquid hydrolysate. Operating conditions at low temperatures (160, 170 °C) with short holding time (5, 10 min) under several concentrations of diluted acid medium (0, 0.1 and 0.2 M) were carried out to investigate the torrefaction severity effects towards the properties of the solid and liquid products. The highest biochar yields of 54.5% and 74.6% are obtained from C. vulgaris ESP-31 and Chlorella sp. GD, respectively under the wet torrefaction conditions with an improvement in the properties for fuel and value-added environmental application. The highest total reducing sugar concentration of 98.11 g/L and 12.08 g/L are obtained in C. vulgaris ESP-31 and Chlorella sp. GD liquid hydrolysates, respectively after acid hydrolysis pretreatment. With the co-production of high total reducing sugar in the liquid hydrolysate that can be utilized for bioethanol production and solid biochar as another value-added product, the acid hydrolysis pretreatment using wet torrefaction can be one of the conversion technologies towards the application of renewable energy production.

Background There is a renewed interest in the utilisation of agricultural by-products, particularly those from crop plants, as a source of functional ingredients. The banana (Musa spp.) is a popular food crop worldwide but its inflorescence is often undervalued, similar to other agricultural by-products. As the banana inflorescence is traditionally consumed as food and medicine, it has the potential to be developed into functional foods. Scope and approach The present review systematically summarises the nutritional attributes, bioactive components and potential health-promoting properties of the inflorescence of the banana plant for the first time. Key Findings and Conclusions: The findings thus far, particularly on the broad array of bioactive chemical constituents in the inflorescence and their corresponding biological activities, seem to justify its proposed use in various food industries. Perspectives on the current status of research and future work potentially leading to the development and commercialisation of the banana inflorescence into value-added products, are also provided. From this review, it is clear that the banana inflorescence has great potential to be developed into useful nutraceuticals and functional foods.

The effective removal of heavy metals and soluble microbial products from wastewater is crucial for ensuring a safe environment and good quality human health. The present work investigated the potential of eggshell (ES) waste as an adsorbent for removing heavy metals and soluble microbial products. ES was firstly used to capture heavy metal ions, and the eggshell–metal (ES-M) complex was then applied to remove soluble microbial products (e.g., proteins) from aqueous solution. In this study, bovine serum albumin (BSA) was selected as a model protein-based contaminant. The equilibrium and kinetic characteristics of soluble protein removed by ES were evaluated in batch mode involving parameters such as metal ions (Cu2+, Zn2+, Ni2+, Co2+), operating temperatures (277–323 K), and particle size of ES (100–700 µm). The isotherm curves were well-fitted by Langmuir–Freundlich model. As the temperature increased from 277 to 323 K, the maximum binding capacity for BSA increased from 25.22 to 34.28 (mg BSA/g ES-Zn). The negative values of ΔG° indicated the spontaneous nature of the protein adsorption, while the kinetic of protein adsorption followed the pseudo-second-order model. ES functionalized with heavy metal ions acted as an effective pseudo-chelating adsorbent for the removal of soluble protein from wastewater. Chelates of Zn–BSA found on the ES complexes were found to be highly stable, indicating a minimal possibility of secondary pollution caused by these Zn- and BSA-containing ES complexes. The ES-Zn complex can be potentially used as an adsorbent for removing soluble microbial products in wastewater prior to the membrane filtration.

© 2020 Elsevier B.V. Fuel-like hydrocarbons (also known as biofuel) isolated from the deoxygenation of fatty acids present different advantages as compared with fossil fuels. In particular, the homogeneous and heterogeneous catalytic deoxygenation methods have been the center of attention during recent years. Although catalytic deoxygenation of fatty acids via heterogeneous catalysis has been widely investigated, there is a high demand to review the progress in using the homogeneous catalysis pathways. Among the various homogeneous pathways, radical-based reactions and transition metal catalysis demonstrate the most promising results in the decarboxylation and decarbonylation processes. It is shown that radical-based reactions are more active in decarboxylation meanwhile the transition metal catalysts are rather selective to decarbonylation of fatty acids. Besides, the reaction conditions and type of catalysts are capable of enhancing biofuel production. Homogenous catalysis provides the huge potential for commercializing viability of biofuel via deoxygenation of fatty acids.

BackgroundThe extraction of lipids from microalgae requires a pretreatment process to break the cell wall and subsequent extraction processes to obtain the lipids for biofuels production. The multistep operation tends to incur high costs and are energy intensive due to longer process operations. This research work applies the combination of radicals from hydrogen peroxide with an organic solvent as a chemical pretreatment method for disrupting the cell wall of microalgae and simultaneously extracting lipids from the biomass in a one-step biphasic solution.ResultSeveral parameters which can affect the biphasic system were analyzed: contact time, volume of solvent, volume ratio, type of organic solvent, biomass amount and concentration of solvents, to extract the highest amount of lipids from microalgae. The results were optimized and up to 83.5% of lipid recovery yield and 94.6% of enhancement was successfully achieved. The results obtain from GC-FID were similar to the analysis of triglyceride lipid standard.ConclusionThe profound hybrid biphasic system shows great potential to radically disrupt the cell wall of microalgae and instantaneously extract lipids in a single-step approach. The lipids extracted were tested to for its comparability to biodiesel performance.

The exploitation of renewable energy sources for delivering carbon neutral or carbon negative solutions has become challenging in the current era because conventional fuel sources are of finite origins. Algae are being used in the development of biophotovoltaic (BPV) platforms, which are used to harness solar energy for bioelectricity generation. In photosynthesis, a very small amount of solar energy absorbed is transformed into chemical energy while the rest is wasted as heat and fluorescence. This energy can be harvested through biophotovoltaic (BPV) platforms to generate electrical power. During photosynthesis, algae consume carbon dioxide and release oxygen, while producing biomass. One of the most important parameters that affect photosynthetic performance of algae is light. Overexposure to light causes photodamage of Photosystem II and impedes electron shuttle from the algal cells to the anode of the BPV devices. In the present study, we studied the effect of varying irradiance levels on the efficiency of our BPV platforms. Algal biofilms were grown from suspension and alginate-immobilized Chlorella sp. (UMACC 313) cultures on ITO-coated glass anodes. The BPV devices were illuminated by four different irradiance levels (30, 90, 150 and 210 μmol photons m-2 s-1) to investigate the effect of different irradiance levels on the power output of the devices. Our prototype Algal Fuel Cell produced maximum power densities of 0.377 mWm-2 from suspension cultures at 90 μmol photons m-2 s-1 and 0.456 mWm-2 from immobilized cultures at 150 μmol photons m-2 s-1. The lowest power output from immobilized cultures was recorded at 210 μmol photons m-2 s-1, thus suggesting that the algae were already experiencing photo-induced stress and partial photoinhibition had occurred at high irradiance level.

© 2019 The Author(s). Background: Microalgae are one of the promising feedstock that consists of high carbohydrate content which can be converted into bioethanol. Pre-treatment is one of the critical steps required to release fermentable sugars to be used in the microbial fermentation process. In this study, the reducing sugar concentration of Chlorella species was investigated by pre-treating the biomass with dilute sulfuric acid and acetic acid at different concentrations 1%, 3%, 5%, 7%, and 9% (v/v). Results: 3,5-Dinitrosalicylic acid (DNS) method, FTIR, and GC-FID were employed to evaluate the reducing sugar concentration, functional groups of alcohol bonds and concentration of bioethanol, respectively. The two-way ANOVA results (p < 0.05) indicated that there was a significant difference in the concentration and type of acids towards bioethanol production. The highest bioethanol yield obtained was 0.28 g ethanol/g microalgae which was found in microalgae sample pre-treated with 5% (v/v) sulfuric acid while 0.23 g ethanol/g microalgal biomass was presented in microalgae sample pre-treated with 5% (v/v) acetic acid. Conclusion: The application of acid pre-treatment on microalgae for bioethanol production will contribute to higher effectiveness and lower energy consumption compared to other pre-treatment methods. The findings from this study are essential for the commercial production of bioethanol from microalgae.

Microalgae, a sustainable source of multi beneficial components has been discovered and could be utilised in pharmaceutical, bioenergy and food applications. This study aims to investigate the sugaring-out effect on the recovery of protein from wet green microalga, Chlorella sorokiniana CY1 which was assisted with sonication. A comparison of monosaccharides and disaccharides as one of the phase-forming constituents shows that the monosaccharides, glucose was the most suitable sugar in forming the phases with acetonitrile to enhance the production of protein (52% of protein). The protein productivity of microalgae was found to be significantly influenced by the volume ratio of both phases, as the yield of protein increased to 77%. The interval time between the sonication as well as the sonication modes were influencing the protein productivity as well. The optimum protein productivity was obtained with 10 s of resting time in between sonication. Pulse mode of sonication was suitable to break down the cell wall of microalgae compared to continuous mode as a lower protein yield was obtained with the application of continuous mode. The optimum condition for protein extraction were found as followed: 200 g/L glucose as bottom phase with volume ratio of 1:1.25, 10 s of resting time for ultrasonication, 5 s of ultrasonication in pulse mode and 0.25 g of biomass weight. The high yield of protein about 81% could be obtained from microalgae which demonstrates the potential of this source and expected to play an important role in the future.

Non-edible Jatropha seed used for biodiesel production has increased due to its high-oil contents in kernel and potential to reduce greenhouse gas emission. High demand for biodiesel generates a large volume of waste. In this study, de-oiled Jatropha seed kernel was torrefied at 200 °C, 250 °C and 300 °C, holding time of 15, 30, 45 and 60 min and particle sizes of 0.5–1.0 and 1.0–2.0 mm to produce solid fuel. Torrefaction performance was highly affected by torrefaction temperature compared with holding time. The enhancement factor of HHV increased up to 1.243 after torrefaction at 300 °C and 60 min with particle size of 0.5–1.0 mm. The large particle size reduces the diffusion rate of torrefaction vapour through internal pores, thereby producing high solid yield and low enhancement in HHV. The analysis of torrefaction severity index shows that HHV increase is highly dependent on the weight loss, thereby directly decreasing the total energy in biochar. Scanning electron microscopy image clearly illustrated that the microparticles on the surface were destroyed to increase the porous structure of the biochar with increasing torrefaction temperature. Severe torrefaction with particle size of 0.5–1.0 mm was an effective approach to increase the energy content of biochar.

International audience; Cesium-aluminosilicate zeolite nanocrystals with ABW framework structure are synthesized free of organic template using hydrothermal approach. The crystallization process of Cs-ABW zeolite nanocrystals by varying the initial gel molar composition, heating temperature and crystallization time was studied. More detailed investigations of the formation of Cs-ABW nanozeolite using a reactive clear precursor hydrogel (4SiO2:1Al2O3:16Cs2O:160H2O) were then carried out. Fully crystalline Cs-ABW nanozeolites were obtained within 120 min at 180 °C and 22 bar, which is considerably faster and safer in comparison to the currently available method involving treatment at 695 °C, 1000 bar and 46 h. The Cs-ABW nanocrystals have grain shape morphology with a mean size of 32 nm and they do not agglomerate for long durations. The nanosized Cs-ABW zeolite has high alumina content (Si/Al ratio = 1.04). These nanocrystals can be prepared in high solid yield (ca. 82%) thus offering a promising route for large-scale production of highly basic zeolite nanoparticles.

H2-Free catalytic deoxygenation of biomass-derived organic compounds is an important technology to produce green hydrocarbons without the relevant carbon footprint associated with H2. In this work, the effects of the crystal size of zeolite Y (Y20: 20 nm, Y65: 65 nm, Y380: 380 nm and Y2750: 2.75 μm) on the deoxygenation reaction of triolein are reported. The reaction is performed under solvent-free conditions without the addition of hydrogen. As the crystal size decreases, the triolein conversion and the yield of deoxygenated products increase. In addition, better product quality is obtained: higher hydrocarbon formation, higher diesel formation, lower formation of heavy hydrocarbons and higher diesel-to-gasoline ratio are observed. The high activity is related to the high concentration of acid sites, with accessible medium acid strength comprised of Bronsted and Lewis acid sites located on the external surface of the crystals. A linear relationship is observed between the rate constant of triolein depletion and the amount of medium strength acid sites. Further conversion of the fatty acids which are obtained from the hydrogenolysis of triolein (first rate-determining step) to deoxygenated products occurs on the surfaces of the zeolite crystals. The better accessibility of the Y20 sample with the smallest crystal size leads to improved catalytic performance. In comparison with previously reported catalysts, H2-free deoxygenation over nanosized zeolite Y appears to be an interesting industrial option to obtain high yields of green diesel.

In recent years, researchers have proven that the employment of natural green components in the biogenesis of nanoparticles from microalgae species is one of the ways to delight the global environment issues. The application of nanotechnology with the exploitation of phycochemical produced from algae species is known as 'phyconanotechnology'. The use of biological compounds by microalgae as reducing agents for the synthesis of inorganic nanoparticles has shown promising results such as cost-effective and environmentally friendly. Different classifications of algae such as brown algae, red algae, green algae, and cyanobacteria are studied for the synthesis of different types of metal nanoparticles. It is also an important motive to acknowledge the mechanisms of the microalgae-mediated biosynthesis of nanoparticles via an intracellular pathway or extracellular pathway. Besides, microalgae species as biogenic sources preclude the use of conventional methods reagents, such as sodium borohydride (NaBH

The full dependency on chemical fertilizers in oil palm plantation poses an enormous threat to the ecosystem through the degradation of soil and water quality through leaching to the groundwater and contaminating the river. A greenhouse study was conducted to test the effect of combinations of biofertilizers with chemical fertilizer focusing on the soil fertility, nutrient uptake, and the growth performance of oil palms seedlings. Soils used were histosol, spodosol, oxisol, and ultisol. The three treatments were T1: 100% chemical fertilizer (NPK 12:12:17), T2: 70% chemical fertilizer + 30% biofertilizer A (CF + BFA), and T3: 70% + 30% biofertilizer B (CF + BFB). T2 and T3, respectively increased the growth of oil palm seedlings and soil nutrient status but seedlings in oxisol and ultisol under T3 had the highest in almost all parameters due to the abundance of more efficient PGPR. The height of seedlings in ultisol under T3 was 22% and 17% more than T2 and T1 respectively, with enhanced girth size, chlorophyll content, with improved nutrient uptake by the seedlings. Histosol across all treatments has a high macronutrient content suggesting that the rate of chemical fertilizer application should be revised when planting using the particular soil. With the reduction of chemical fertilizer by 25%, the combined treatment with biofertilizers could enhance the growth of the oil palm seedlings and soil nutrient properties regardless of the soil orders.

International audience; 1-Propyl-2,3-dimethyl-1H-imidazol-3-ium ([pmIm] +), 3-(2,3-dihydroxypropyl)-1,2-dimethyl-1Himidazol-3-ium ([dhmIm] +) and 1-benzyl-2,3-dimethyl-1H-imidazol-3-ium ([bzmIm] +) cations were used as organic templates for crystallizing SAPO-5 with AFI microporous framework. The physicochemical influences of the functional groups of the templates (e.g. polarity/hydrophilicity, molecular dimension and size) on SAPO-5 formation were investigated. The results revealed that the crystallization rate, crystallinity and solid yield could be enhanced by increasing the polarity/hydrophilicity of the templates. In addition, the isomorphous Si substitution, morphology and particle size of the resulted SAPO-5 were also affected by the substituted groups of the imidazolium 2 templates. The thermogravimetry results further supported that the selection of organic template with proper polarity/hydrophilicity could be crucial to obtain SAPO-5 with high porosity (SBET, Smic, Sext and Vtotal) as high polar/hydrophilic template exhibited stronger chemical interaction with the AFI framework during template removal process via calcination process.

Recent trend to recover value-added products from wastewater calls for more effective pre-treatment technology. Conventional landfill leachate treatment is often complex and thus causes negative environmental impacts and financial burden. In order to facilitate downstream processing of leachate wastewater for production of energy or value-added products, it is pertinent to maximize leachate treatment performance by using simple yet effective technology that removes pollutants with minimum chemical added into the wastewater that could potentially affect downstream processing. Hence, the optimization of coagulation-flocculation leachate treatment using multivariate approach is crucial. Central composite design was applied to optimize operating parameters viz. Alum dosage, pH and mixing speed. Quadratic model indicated that the optimum COD removal of 54% is achieved with low alum dosage, pH and mixing speed of 750 mgL−1, 8.5 and 100 rpm, respectively. Optimization result showed that natural pH of the mature landfill leachate sample is optimum for alum coagulation process. Hence, the cost of pH adjustment could be reduced for industrial application by adopting optimized parameters. The inherent mechanism of pollutant removal was elucidated by FTIR peaks at 3853 cm−1 which indicated that hydrogen bonds play a major role in leachate removal by forming well aggregated flocs. This is concordance with SEM image that the floc was well aggregated with the porous linkages and amorphous surface structure. The optimization of leachate treatment has been achieved by minimizing the usage of alum under optimized condition.

Nickel-based catalysts play an important role in the hydrogen-free deoxygenation for the production of biofuel. The yield and quality of the biofuel are critically affected by the physicochemical properties of NiO supported on nanosized zeolite Y (Y65, crystal size of 65 nm). Therefore, 10 wt% NiO supported on Y65 synthesized by using impregnation (IM) and deposition&ndash, precipitation (DP) methods were investigated. It was found that preparation methods have a significant effect on the deoxygenation of triolein. The initial rate of the DP method (14.8 goil&middot, h&minus, 1) was 1.5 times higher than that of the IM method (9.6 goil&middot, 1). The DP-Y65 showed the best deoxygenation performance with a 80.0% conversion and a diesel selectivity of 93.7% at 380 &deg, C within 1 h. The outstanding performance from the DP method was due to the smaller NiO particle size (3.57 &plusmn, 0.40 nm), high accessibility (H.F value of 0.084), and a higher Br&ouml, nsted to Lewis acidity (B/L) ratio (0.29), which has improved the accessibility and deoxygenation ability of the catalyst. The NH4+ released from the decomposition of the urea during the DP process increased the B/L ratio of zeolite NaY. As a result, the pretreatment to convert Na-zeolite to H-zeolite in a conventional zeolite synthesis can be avoided. In this regard, the DP method offers a one-pot synthesis to produce smaller NiO-supported nanosized zeolite NaY with a high B/L ratio, and it managed to produce a higher yield with selectivity towards green diesel via deoxygenation under a hydrogen-free condition.

Highly active metal chlorides grafted on silicoaluminophosphate number 5, MClx/SAPO-5 (M = Cu, Co, Sn, Fe and Zn) catalysts via simple grafting of respective metal chlorides (MClx) onto SAPO-5 are reported. The study shows that thermochemical treatment after grafting is essential to ensure the formation of chemical bondings between MClx and SAPO-5. In addition, the microscopy, XRD and nitrogen adsorption analyses reveal the homogeneous distribution of MClx species on the SAPO-5 surface. Furthermore, the elemental microanalysis confirms the formation of Si&ndash, O&ndash, M covalent bonds in ZnClx/SAPO-5, SnClx/SAPO-5 and FeClx/SAPO-5 whereas only dative bondings are formed in CoClx/SAPO-5 and CuClx/SAPO-5. The acidity of MClx/SAPO-5 is also affected by the type of metal chloride grafted. Thus, their catalytic behavior is evaluated in the acid-catalyzed acylation of 2-methylfuran under novel non-microwave instant heating conditions (90&ndash, 110 &deg, C, 0&ndash, 20 min). ZnClx/SAPO-5, which has the largest amount of acidity (mainly Lewis acid sites), exhibits the best catalytic performance (94.5% conversion, 100% selective to 2-acetyl-5-methylfuran) among the MClx/SAPO-5 solids. Furthermore, the MClx/SAPO-5 solids, particularly SnClx/SAPO-5, FeClx/SAPO-5 and ZnClx/SAPO-5, also show more superior catalytic performance than common homogeneous acid catalysts (H2SO4, HNO3, CH3COOH, FeCl3, ZnCl2) with higher reactant conversion and catalyst reusability, thus offering a promising alternative for the replacement of hazardous homogeneous catalysts in Friedel&ndash, Crafts reactions.

International audience; Nanoscale zeolites are very attractive for advanced applications such as in catalysis, adsorption, supports, sensors and carriers. Green synthesis of these materials is highly appreciated aiming to increase product yield while chemical waste and production cost can be reduced. Here we report high-yield, low-cost and green synthesis of nanosized Cs-ABW zeolite by recycling and using the non-reacted mother liquors waste solutions produced from the hydrothermal Cs-ABW zeolite synthesis. The nanocrystalline Cs-ABW solid product of each successive batch was collected and characterized while the non-reacted mother liquors were recovered and re-used for subsequent synthesis of nanozeolites. The synthesized Cs-ABW zeolite nanocrystals from three subsequent cycles possessed fairly similar properties and they exhibited excellent catalytic performance in Henry (nitroaldol) reaction of benzaldehyde and nitroethane thanks to their basic sites, (Si-O-Al)-Cs + , located at the external surface of the zeolite. This approach hence suggests a low-cost and eco-friendly preparation of Cs-ABW zeolite nanocrystals since less chemical waste is disposed while the product yield can be significantly improved which are ideal for industrial scale-up process.