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Biodiesel production from waste palm cooking oil (WPCO) was studied. Calcium oxide with a strontium ion additive (Sr-CaO) was employed as a catalyst in transesterification reaction of used palm oil with methanol. The Sr-CaO was synthesized by co-precipitation method between SrCl2 and Ca(NO3)2, then calcined at 900°C for 5 h. The catalyst was characterized by using thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), Scanning electron microscope (SEM), and Fourier transform infrared spectrometer (FT-IR). The morphology and elements content of Sr and Ca in the catalyst were confirmed by SEM-EDX. The approximate catalyst diameter is 12.6±5.9 µm. The highest conversion was 99.33% (the reaction time 3 h, 5%w/w catalyst, methanol to oil molar ratio 9:1 and reaction temperature 80°C). The catalyst can be used up to the sixth cycles with a good yield. The synthesized biodiesel meet the requirement of standard biodiesel (EN 14103 and ASTM D445). These findings suggest that calcium oxide with a strontium ion additive (Sr-CaO) is an effective renewable biodiesel catalyst.

A simple hydrothermal synthesis of CeO2 was implemented to obtain a series of CeO2-supported gold (Au) catalysts, used for the total oxidation of propene/toluene/CO gas mixtures and the oxidation of CO. CeO2 preparation started from a cerium hydrogen carbonate precursor using a range of different hydrothermal temperatures (HT) from 120 to 180°C. High-resolution transmission electron microscopy, X-ray diffraction, and H2-temperature-programmed reduction data indicated that CeO2 morphology varied with the HT, and was composed of the more active (200) surface. Following Au deposition onto the CeO2 support, this active crystal plane resulted in the most widely dispersed Au nanoparticles on the CeO2 support. The catalytic performance of the CeO2-supported Au catalysts for both oxidation reactions improved as the reducibility increased to generate lattice oxygen vacancies and the number of adsorbed peroxide species on the CeO2 support increased due to addition of Au. The Au catalyst on the CeO2 support prepared at 120°C was the most active in both propene/toluene/CO oxidation and independent CO oxidation.

Immobilization of microbe cells has been considered as a potential alternative for enhancing biobutanol productivity through acetone-butanol-ethanol (ABE) fermentation. Vetiver grass (VG; Vetiveria zizanoides) pretreated by sodium hydroxide (NaOH) or sulphuric acid was used as carrier for immobilized Clostridium beijerinckii TISTR 1461 in ABE fermentation. The removal of the lignin and hemicellulose fractions of VG during the pretreatment resulted in structural changes, especially an increased crystallinity and surface area. The VG pretreated with 6% (w/v) NaOH at 120 °C for 6 h had the best potential as a carrier in ABE fermentation, giving a butanol and total ABE concentration of 11.6 g/L and 19.8 g/L, respectively, approximately 1.3-fold greater than that of the free-cell system. The VG samples were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and surface area analyses.

A simple hydrothermal synthesis of CeO

Titania (TiO2) nanoparticles (NPs) with different morphologies (spherical, rod-shaped, and mixed) were prepared by hydrothermal treatment of different nitric acid (HNO3)/titanium (IV) isopropoxide (TTIP) molar ratios (0.25, 0.5, 1.0, and 1.7) at different hydrothermal temperatures (90, 150, 200, and 250 °C), hydrothermal times (6, 12, and 24 h), and calcination temperatures (500, 625, and 750 °C). The crystalline structure, morphology, and surface texture of the obtained TiO2 NPs were characterized by X-ray diffraction, nitrogen adsorption–desorption isotherm, field emission-scanning electron microscopy, and high resolution-transmission electron microscopy analyses. Under a larger HNO3: TTIP molar ratio, higher hydrothermal temperature, and higher hydrothermal time, the spherical mixed anatase–rutile phase TiO2 NPs were converted to a nanorod (NR)-shaped rutile phase (TiO2-R). The TiO2-R NRs gave the highest methanol conversion level (65%) and hydrogen yield (45%) in the oxidative steam reforming of methanol at 400 °C.

Ceria (CeO2) supports were synthesized by hydrothermal treatment with different Cetyltrimethylammonium bromide (CTAB) concentrations (CeO2-X: 0.135, 0.270, 0.540 and 1.080, where X is the CTAB concentration in mmol). The micro-structures of bundle-like ceria nanorods (NR) were produced by thermal treatment of the crystalline Ce(OH)CO3 precursor. The exposed crystal planes of (2 0 0) and (1 1 1), corresponding to the d-spacing of 0.27 and 0.31 nm, were confirmed by high resolution-transmission electron microscopy (HR-TEM). The fundamental characteristics of CeO2-0.135 led to the highest surface area, surface area normalized reducibility and oxidized gold species (Aun+/Au0) on the surface, relatively higher oxygen vacancies and a smaller average gold particle size (7.9 nm). The activity results show that the Au/CeO2-0.135 has the highest methanol conversion and H2 production rate for oxidative steam reforming of methanol (OSRM). The reducibility and gold particle size played a crucial role in determining the H2/CO2 ratio at the temperature of 200 °C.

The effect of the ceria–zirconia (CeO2–ZrO2) support composition of a gold (Au) catalyst (Au/Ce1−xZrxO2, where x is the molar ratio), prepared by deposition–precipitation, on its catalytic activity was investigated in the preferential carbon monoxide (CO) oxidation. A maximum CO conversion level of 94% was obtained with 1% by weight Au/Ce0.75Zr0.25O2 at 50 °C, while the presence of water and carbon dioxide in the feed stream had only a slight effect on the catalytic activity. Catalyst characterizations were performed to investigate the effect of the Ce:Zr molar ratios on the redox properties and physicochemical properties of the obtained Au/CeO2–ZrO2 catalysts. It was found that a certain amount of Ce in the Au/CeO2–ZrO2 catalyst promoted solid solution formation and facilitated the activity of Au3+ and Au0 nanoparticles with a small crystallite size. The enhanced catalytic activity of Au/Ce0.75Zr0.25O2 was attributed to the presence of more oxygen vacancies, easier reducibility, and appropriate amount of Au3+ species, as confirmed by Fourier transform Raman spectroscopy and hydrogen-temperature-programme reduction analyses, respectively. The catalytic activity showed a high stability for a long period of time (28 h).

Sulfuric acid (H2SO4) pretreated corncob-derived residue was used as a starting material to prepare solid acid catalysts using different sulfonation chemicals (H2SO4, p-toluenesulfonic acid (TsOH) and H2SO4/TsOH mixtures) for biodiesel production from the esterification of oleic acid with methanol. Effects of the different sulfonation agents on the properties of the derived carbon-based materials were investigated using various characterization techniques. Lignin residues were obtained after the H2SO4 pretreatment step, and high lignin-containing carbon-based catalysts of ca. 69% (w/w) lignin were derived after sulfonation with H2SO4. Employing TsOH or H2SO4/TsOH mixtures for sulfonation gave materials with a higher carbon/hydrogen (C/H) ratio, indicating a relatively effective carbonization compared to that with H2SO4 sulfonation. The catalytic activity of the sulfonated corncob in the esterification of oleic acid with methanol was influenced by the acid density, acid strength and porous structure of the sulfonated materials. High methyl oleate yields (>80% after 8 h at 60 °C) were achieved using the acid catalyst obtained from either H2SO4 or TsOH sulfonation, whereas those from H2SO4/TsOH sulfonation gave slightly lower yields. Thus, the use of the non-volatile TsOH solid as a ‘greener’ sulfonating agent for the production of carbon-based solid acid catalysts with a high catalytic activity in the esterification reaction is supported.

In this work, response surface methodology (RSM) was utilized to optimize the biodiesel yield of the transesterification reaction. A novel solid carbon-supported potassium hydroxide catalyst derived from the pyrolysis of cultivated banana (Musa sapientum) peels and potassium carbonate (K2CO3) was used as the catalyst for biodiesel production. A five-level (− 2, − 1, 0, + 1, and + 2) RSM with a four-factor central composite design of independent variable factors (methanol to palm oil molar ratio (6:1–18:1), catalyst loading (3–7 wt.%), reaction time (30–150 min), and reaction temperature (50–70 °C)) were randomly setup using the Design of Experiment program. The 30 wt.% K2CO3 catalyst calcined at 600 °C under atmosphere pressure exhibited the highest catalytic activity, since the pyrolysis ash was rich in K that formed a basic heterogeneous catalyst. Within the range of selected operating conditions, the optimized methanol:oil molar ratio, catalyst loading, reaction time, and reaction temperature were found to be 15:1, 4 wt.%, 120 min, and 65 °C, respectively, to give a biodiesel yield of 99.16%. The actual biodiesel yield of 98.91% was obtained under the predicted optimal conditions. The high R2 (96.76%) and R2adj (92.97%) values indicated that the fitted model showed a good agreement with the predicted and actual biodiesel yield.

Metal-doped graphitic carbon nitride (MCN) materials have shown great promise as effective photocatalysts for the conversion of acetic acid to carbon dioxide under UV–visible irradiation and are superior to pristine carbon nitride (g-C3N4, CN). In this study, the effects of metal dopants on the physicochemical properties of metal-doped CN samples (Fe-, Cu-, Zn-, FeCu-, FeZn-, and CuZn-doped CN) and their catalytic activity in the photooxidation of acetic acid were investigated and discussed for their correlation, especially on their surface and bulk structures. The materials in the order of highest to lowest photocatalytic activity are FeZn_CN, FeCu_CN, Fe_CN, and Cu_CN (rates of CO2 evolution higher than for CN), followed by Zn_CN, CuZn_CN, and CN (rates of CO2 evolution lower than CN). Although Fe doping resulted in the extension of the light absorption range, incorporation of metals did not significantly alter the crystalline phase, morphology, and specific surface area of the CN materials. However, the extension of light absorption into the visible region on Fe doping did not provide a suitable explanation for the increase in photocatalytic efficiency. To further understand this issue, the materials were analyzed using two complementary techniques, reversed double-beam photoacoustic spectroscopy (RDB-PAS) and electron spin resonance spectroscopy (ESR). The FeZn_CN, with the highest electron trap density between 2.95 and 3.00 eV, afforded the highest rate of CO2 evolution from acetic acid photodecomposition. All Fe-incorporated CN materials and Cu-CN reported herein can be categorized as high activity catalysts according to the rates of CO2 evolution obtained, higher than 0.15 μmol/min−1, or >1.5 times higher than that of pristine CN. Results from this research are suggestive of a correlation between the rate of CO2 evolution via photocatalytic oxidation of acetic acid with the threshold number of free unpaired electrons in CN-based materials and high electron trap density (between 2.95 and 3.00 eV).

Acidic aqueous ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate/acetic acid in combination with a metal salt (FeCl3) pretreatment was investigated for the pretreatment of Napier grass. This research focused on the effects of the FeCl3 concentration (20–100 mM), pretreatment time (10–190 min), and temperature (40–160 °C) during the pretreatment under microwave irradiation on the obtained total sugar yield after subsequent enzymatic hydrolysis. The optimum condition of these variables was determined by response surface methodology and compared with acidic aqueous IL pretreatment. The untreated and different pretreated NG samples were characterized using X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermogravimetric analyses. The effect of the type of anti-solvent (biomass regenerated solvent) on the obtained total reducing sugar yield by enhancing the cellulose content in the pretreated biomass was also studied. The results showed that an acidic aqueous IL could remove more lignin than the other pretreatments. The addition of FeCl3 in the acidic aqueous IL pretreatment had a significant effect on the total reducing sugar yield.

During recessions, either declines in actual capital or increases in required capital may intensify pressures on banks. One way for banks to boost their capital ratios is by reducing their lending. However, one effect of systematic reductions in the supply of bank loans during recessions would likely be to accentuate the magnitudes of macroeconomic fluctuations. To reduce this source of “procyclicality”, it has been proposed that Basel II include “escape clauses”. Such clauses might, for example, operate so as to raise required bank capital during macroeconomic expansions and reduce it during downturns. Apart from formal escape clauses, procyclicality might be reduced or even reversed in practice if banks exercise sufficient discretion in reporting their charge-offs and loan loss provisions. We propose two hypotheses about the past cyclicality of such discretion. We hypothesize that individual banks tended to report fewer charge-offs and provisions when the banking system was troubled than when it was generally healthier. That suggested our second hypothesis: Banks tended to cluster more when the banking industry was troubled. Banks would maximize the value of their reporting discretion by clustering more then; being similar to other banks raised the likelihood that a bank would be able to exert reporting discretion when it encountered difficulties, because other, similar banks, and thus the banking system as a whole, would likely be troubled at the same time. We found some support for our hypotheses at large U.S. banks. During the late 1980s, when banking was troubled and bank capital ratios were low, individual banks reported fewer charge-offs, ceteris paribus, when the capital ratios of their peers were lower. During the late 1990s, in contrast, when capital ratios were higher, charge-offs at individual banks were not systematically related to the capital ratios of peer banks. We also found that the equity and the asset betas of individual banks tended to cluster more when banking was more troubled than they did when banking was less troubled.

Streptococcosis is a major disease that causes huge economic losses to tilapia farming in Thailand. Breeding for Streptococcosis agalactiae resistant strains using the pedigree BLUP method has proven an effective approach to control the disease in red tilapia, but the accuracy of selection is relatively low. Genomic selection, which is based on genome-wide markers to predict genomic breeding values of selection candidates, provides a powerful approach for accelerating genetic progress and producing permanent gains in the population. We evaluated the implementation of four genomic prediction models, GBLUP, ssGBLUP, BayesB and BayesC, using 19 sets of SNP markers (ranging from 500 to 24 582 SNPs) in 886 fish challenged with S. agalactiae. The accuracy of prediction was estimated using a five-fold cross-validation approach, with 708 and 178 individuals sampled for the training and validation sets respectively. Prediction of the accuracy of each of the models was improved substantially compared with PBLUP (10%) using 1000 informative SNPs. The GBLUP model (65%), which required less computing time, outperformed the remaining models - ssGBLUP (53%), BayesB (47%) and BayesC (42%).

The conversion of glucose and fructose to 5-hydroxymethylfurfural (HMF) was investigated using a series of functionalized SBA-15 catalysts in a glass tube reactor. The synthesized SBA-15 as a support was grafted with various organosilanes in order to acquire the acid-modified SBA-15 (SBA-A), acid- and hydrophobicity-modified SBA-15 (SBA-AC), and base-modified SBA-15 (SBA-N) catalysts. Effects of the reaction temperature and time, reactant concentration, and catalyst loading level on the catalyst performances in this reaction, in terms of the hexose conversion level, product yield, and selectivity, were evaluated. The prepared catalysts were extensively characterized by X-ray diffractometry, nitrogen adsorption–desorption, Fourier transform infrared spectrometry, CHN/S elemental analysis, solid-state nuclear magnetic resonance spectroscopy, contact angle measurement, and acid–base titration. The hexose-to-HMF reaction was greatly enhanced by increasing the reaction temperature, whereas the other factors had only a minor effect. In the case of the glucose-to-HMF production, the SBA-N catalyst exhibited reasonably high levels of glucose conversion and HMF yield, but its catalytic activity was pretty low for the fructose-to-HMF reaction. Herein, fructose was identified as an intermediate substance for further dehydration to HMF. The different catalyst types provided different functions, where isomerization required a basic property, whereas dehydration was optimal over an acidic one. Suppression of the levulinic acid formation was obtained via an increased hydrophobicity of the SBA-AC catalyst.

Titania (TiO2) supports with anatase (A), mixed, and rutile (R) crystalline phases were prepared via the hydrothermal treatment of titanium isopropoxide and investigated as a catalyst for the oxidative steam reforming of methanol (OSRM). The different TiO2 phases were synthesized using different types of acid: acetic (HAc), nitric, and a mixture of HAc and hydrochloric acids, and hydrothermal (90 or 200 °C) or calcination (560 or 750 °C) temperatures. X-ray diffraction analysis revealed the crystal structure of successfully synthesized TiO2 with different TiO2-A:TiO2-R ratios. The TiO2-R with (110) and (101) planes showed the highest catalytic activity for OSRM in the temperature range of 200–400 °C.

The potential of selection to improve resistance to streptococcosis was evaluated in a commercial population of Nile tilapia in Thailand. The base generation (G0) consisted of offspring from 98 sires and 149 dams using a partly nested design. At 60 days post-hatch, 30 fish from each family were injected intraperitoneally with a Streptococcosis agalactiae solution (1 × 109 CFU/ml) and evaluated for 14 days. Disease resistance was recorded as the number of days from challenge until death (DD) and as a binary (BIN) trait (dead/alive) on day 14. Three models were used for genetic analyses: Cox frailty model for DD; animal model for DD; and animal model for BIN. Age at challenge was fitted as a covariate and contemporary group as fixed or random effect, depending on the model. Fish from the 18 most resistant families were selected to produce the first generation (G1). Heritability estimates for G0 were 0.22, 0.14 ± 0.02 and 0.11 ± 0.02 for the Cox, linear DD and linear BIN models, respectively. Selection response indicated that the risk of death decreased to 54%, survival time increased to 3.4 days and survival rate increased to 21%. These results suggest that genetic improvement is possible for this population.

Immobilization is a simple technique in which microorganisms adhere and agglomerate onto the porous material’s surface, resulting in a higher cell density, cell tolerance, and productivity. Acetone-butanol-ethanol (ABE) fermentation using immobilized Clostridium beijerinckii JCM 8026 on Napier grass (Pennisetum purpureum) chemically pretreated with H2SO4, NaOH, and 1-ethyl-3-methylimidazolium acetate (EMIM-OAc) was compared in order to investigate the effect of the treatment on butanol production. X-ray diffraction, Fourier-transform infrared spectroscopy, and surface area measurement analyses indicated that the alkaline-pretreated Napier grass sample had the highest crystalline level with the lowest lignin content (lignin/cellulose) and a high surface area compared with other pretreated samples, suggesting its potential as an immobilized material. The fermentation was operated in a batch system for 5 days with an initial glucose level of 60 g/L. Clostridium beijerinckii JCM 8026 immobilized on the NaOH-treated Napier grass gave the highest butanol concentration (8.99 g/L), which corresponded to a 24.7% and 25.6% higher concentration than that when the cells were immobilized on untreated Napier grass and free cell culture, respectively. It is likely that immobilization on NaOH-treated Napier grass increased the cells’ protection from environmental stresses and prevented their washing out due to its swollen structure within an enlarged surface area.

Ceria (CeO2) supports, synthesized by hydrothermal treatment with different synthesis time (CeO2-X h, where X is the synthesis time in h) in the presence of the surfactant cetyltrimethyl ammonium bromide, were used as supports for gold (Au) catalysts. The synthesis time significantly affects the morphological structure and crystallite size of CeO2, where CeO2-2 h has the smallest crystallite size with coexisting nanorods and nanoparticles. Transmission electron microscopy analysis confirms the morphology of CeO2 with distinctive (110), (100) and (111) planes, in agreement with interplanar spacings of 0.19, 0.27 and 0.31, respectively. However, the morphology of CeO2-8 h and CeO2-48 h is mainly a truncated octahedral with crystal planes (111) and (100) accompanied by an interplanar spacing of 0.31 and 0.27 nm, respectively. The CeO2-X h supports and those with a 3 wt% Au loading (Au/CeO2-X h) were investigated in the oxidative steam reforming of methanol at temperatures between 200 and 400 °C. The Au/CeO2-2 h gave the highest methanol conversion level and hydrogen yield at a low temperature of 250 °C. This superior catalytic performance results from the good interaction between the metal and support and the well-distributed Au species on the CeO2 support.

Copper oxide on ceria supports (CuO/CeO2) were investigated as catalysts for the oxidative steam reforming of methanol (OSRM) reaction at 200–400 °C. Different shapes of CeO2 were obtained, as rod-, mixed- (rod and cube) and cube-shaped with an exposed surface of (110) + (100), (110) + (100) and (100) planes by variation in the hydrothermal synthesis temperature (100–220 °C). The CuO was deposited on CeO2 by deposition–precipitation at a nominal 10% by weight and the obtained CuO/CeO2 catalysts were characterized. The morphological structure of CeO2 influenced the catalytic activities in the OSRM reaction. The CuO/rod-shaped CeO2 (CuO/CeO2-R) gave the highest turnover frequency (TOF) and a CO concentration of less than 1% (v/v). The high catalytic performance of CuO/CeO2-R involved the well-dispersed CuO nanoparticles, level of Cu+ species as the active site, improved reducible oxide, number of relative oxygen vacancies and the stronger interaction between CuO and CeO2.

The combination of the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate with either water or dimethyl sulfoxide (DMSO) as a co-solvent was applied for the pretreatment of Napier grass under microwave irradiation at 150 °C for 1 h in order to enhance the subsequent cellulase enzymatic hydrolysis of the cellulose to sugars via increased enzyme accessibility. The influence of the IL/water and IL/DMSO (at different IL/DMSO (v/v) ratios) pretreatment on the structural changes of the Napier grass was examined using X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analyses. The transformation of cellulose I in the IL/DMSO pretreated Napier grass was clearly observed. The results indicated that cellulose structural changes occurred and a higher yield of fermentable sugars was obtained from the subsequent enzymatic hydrolysis for the pretreated Napier grass samples with a high crystallinity index.

This study presents results of selection response to Streptococcosis agalactiae (SA) resistance in a commercial stock of red tilapia (Oreochromis spp.) after one generation of selection. Families were produced from 93 males and 128 females using a nested design (1 male: 2 females). At 60 days post-hatch, 30 fish from each family were challenged by intraperitoneal injection of bacterial solution (SA strain AQSA01) at the 96 h LD50 concentration (1 × 109 CFU mL−1) and observed for 14 days. Disease-resistance was measured as a binary trait (dead/alive) and as survival time, or the number of days from challenge initiation until death. Animal and sire-dam models were applied with body weight fitted as a covariate, whereas tank and generation were treated as fixed effects. Data from 128 full-sib and 35 half-sib families was used to estimate variance components using ASREML version 4.1. Heritability estimates for the base generation (G0) were highest, 0.25 ± 0.12 for binary data on the liability scale and 0.20 ± 0.08 for days until death. Breeding candidates in G0, selected from the top 10 high-ranking families based on their estimated breeding values (EBVs), were used to produce 25 full- and six half-sib families. When data from G0 and G1 were combined, heritability estimates were 0.29 ± 0.11 and 0.27 ± 0.08 for threshold sire-dam and animal models, respectively. The realized genetic gain was 2.53 days for survival time, equivalent to about a 58% improvement from 4.3 days in the base generation. In terms of binary response, the probability that the G1 fish survived to the end of challenge period increased 10% from the base generation. This study demonstrates a significant selection potential for increased disease-resistance to S. agalactiae in red tilapia.

In this study, the optimal conditions for the ionic liquid pretreatment of rice straw by microwave irradiation was identified by Response Surface Methodology (RSM). The maximum level of sugar concentration of 19.59 g/L was derived when rice straw was pretreated at 162 °C for 48 min and further hydrolyzed by enzymatic saccharification. The comparison of chemical pretreatment was performed using ionic liquid, alkaline, and acid to evaluate the effectiveness and effect structural changes of rice straw. Nevertheless, the total sugar yield from this ionic liquid pretreatment was 13% lower than alkaline (NaOH) pretreatment. All hydrolysates from chemical pretreatment were subjected for use as a culture medium for Clostridium beijerinckii TISTR 1461 in acetone–butanol–ethanol (ABE) fermentation. The results suggested that residue ionic liquid affects microbial growth, so a detoxification step was cautiously considered. Additionally, using hydrolysate of the rice straw pretreated by NaOH as a substrate, isobutyraldehyde was found in the fermentation broth, suggesting that C. beijerinckii TISTR 1461 can produce isobutanol in proper conditions.

Oxidative steam reforming of methanol over monometallic gold (Au) and bimetallic Au-copper (Cu) supported on ceria-zirconia (CeO2 ZrO2) was examined over the temperature range of 200–400 °C in a fixed-bed reactor. The composition of CeO2 ZrO2 supports was also studied for their catalytic activity. The Au/Ce0.75Zr0.25O2 catalyst exhibited the highest methanol (CH3OH) conversion level (96.7%) and hydrogen (H2) yield (59.7%) due to the formation of a homogeneous Ce1-xZrxO2 solid solution. When Cu was introduced in the Au catalysts, all of the bimetallic catalysts presented a better stability for CH3OH conversion as well as H2 yield in comparison to the monometallic catalysts, which was due to the partial electron transfer from Cu to Au metals. The performance of the Au Cu/Ce0.75Zr0.25O2 catalysts, which was evaluated under identical conditions, was ranked in the order: 3Au1Cu > 1Au3Cu > 1Au1Cu.

A highly active bi-functional catalyst system for the conversion of high free fatty acid content oil feedstock, and waste cooking oil to fatty acid methyl ester (FAME), is described. Tungsten loaded CaO/hydroxyapatite materials containing both basic, and acidic sites were derived from addition of 12-phosphotungstic acid to powdered bovine bone (BV), followed by calcination at 750 °C. Addition of 10% tungsten afforded 10 W/BV, which catalyzes FAME production from high acid value oil feedstock (24.38 mg KOH/g of oil) in 7 h at 120 °C at a methanol:oil ratio of 6:1. Conversion of waste cooking oil to FAME via simultaneous transesterification/esterification can be achieved in 5 h at 100 °C and at a methanol:oil ratio of 6:1, significantly more efficient than achievable using other bi-functional catalyst systems. The 10 W/BV catalyst system, readily prepared from a cheap, biomass derived support containing basic sites, is reusable, and allows for the production of fuel quality FAME in high yields from waste cooking oil, allowing for sustainable use of an otherwise wasted resource.

Partial hydrogenation of soybean oil (SO)-derived biodiesel, as fatty acid methyl esters (FAMEs), over mesoporous palladium (Pd)/SBA-15 materials was examined in a semi-batch reactor. The amount of Pd/SBA-15 catalyst was varied from 0.5–1% by weight (wt%) of the SO feedstock. The selectivity of saturated FAMEs (C18:0), which contribute to an excellent oxidative stability but undesirable cold flow properties, over the Pd/SBA-15 catalyst at different wt% was poor after a 4-h reaction period. To improve the catalytic performance, zirconium (Zr) species were incorporated in the SBA-15, resulting in Zr-SBA-15 with tunable acidity and pore properties. Partial hydrogenation of SO-FAME over 0.75 wt% Pd/xZr-SBA-15 catalysts (where x is the Zr/silicon (Si) molar ratio and ranged from 0.01 to 0.11) was performed for 2 h. The catalytic performance and the selectivity towards trans-monounsaturated FAMEs (trans-C18:1), in terms of the turnover frequency (TOF) and trans-C18:1/cis-C18:1 ratio, respectively, were considered at 10% and 80% conversion levels of diunsaturated FAMEs (C18:2). The incorporation of Zr into SBA-15 resulted in an enhanced TOF due to the greater adsorption of both H2 and the basic double bonds of FAME molecules on the electron-deficient catalyst surfaces. The TOF for the Pd/xZr-SBA-15 catalysts increased as the Zr/Si molar ratio increased up to 0.07, and then slightly dropped at higher Zr/Si molar ratios, presumably due to the hindrance of adsorbed-reacted FAME molecules with strong adsorption and the worsening of physical properties, i.e. pore width (DP). The selectivity towards trans-C18:1 was directly correlated with the Zr/Si molar ratio. Since the strong adsorption of FAME molecules took place on the catalyst surface, the high level of trans-C18:1 was consequently generated. The oxidative stability of the partially hydrogenated biodiesels was improved by more than four-fold compared to that of the starting SO-FAMEs.

Palladium/silica (Pd/SiO2) and Pd–M/SiO2 catalysts, where M stands for sodium (Na), calcium (Ca) or barium (Ba), were studied for their catalytic ability in the partial hydrogenation of soybean oil...

MCM-41 has been hydrothermally synthesized using fumed silica (SiO2) and silatrane [Si(TEA)2] as silica sources. Pd nanoparticles were successfully impregnated to the mesoporous MCM-41 supports. Soybean oil methyl ester was partially hydrogenated by the Pd/MCM-41-SiO2 and Pd/MCM-41-silatrane catalysts under a mild condition (low temperature and pressure). Both catalysts could rapidly and selectively convert the polyunsaturated fatty acid methyl esters (C18:3 and C18:2) to monounsaturated fatty acid methyl esters (C18:1) at 100 °C and 0.4 MPa H2 within 4 h. The results verified that the Pd/MCM-41-silatrane catalyst with the greater surface of Pd active sites had higher catalytic activity, representing in term of turnover frequency (TOF), in partial hydrogenation than Pd/MCM-41-SiO2 under both C18:2 conversions of 40% and 60%. Even if the lower selectivity toward cis-C18:1 was obtained for the former. In addition to the better stable structure of MCM-41-silatrane support as compared to MCM-41-SiO2 support, silatrane precursor is more favorable to diminish the extent of complete hydrogenation than fumed silica as it provided the lower index. Even though, this silica precursor sues for more synthetic step. Due to the higher oxidative stability of Pd/MCM-41-SiO2, MCM-41-SiO2 support was further studied for the later research. When varying the Pd loadings in 0.5–2 wt.% on MCM-41-SiO2 support, the Pd(2)/MCM-41-SiO2 catalyst gave the highest performance (TOF) whether the complete hydrogenation was concurrently accompanied. Results signify that the nature of the silica source and the Pd concentration modified the surface active sites and size distribution of metallic particles, which determine the catalytic reactivity and selectivity.

Ceria (CeO2) with different crystal-planes were used as supports to synthesize gold (Au)/CeO2 catalysts for the preferential oxidation of carbon monoxide (CO). A CeO2 morphology-dependent Au-CeO2 interaction was observed. Au/CeO2-R in this present work performed the outstanding activity at lower temperature than ever since other works were reported. The Au catalyst supported on rod-shaped CeO2 exhibited the highest CO conversion level of 97.9% at 30 °C, followed by that on polyhedral- (94.0%), cube- (74.0%) and octahedral- (27.7%) shaped CeO2. The catalytic activities were strongly affected by the CeO2 crystal-planes and Au active species. The rod-shaped CeO2 enclosed by (1 1 0) and (1 0 0) planes might interact strongly with Au species, generating the most accessible active sites to absorb/desorb and activate the CO and oxygen molecules. The octahedral-shaped CeO2 enclosed by the (1 1 1) plane had the lowest catalytic activity since the (1 1 1) plane is the most stable and irreducible of the CeO2 (1 1 1), (1 0 0) and (1 1 0) planes, accounting for its decreased catalytic activity.

Waste gastropod shells and animal bones are one of the richest sources of calcium carbonate and have been utilized, after suitable treatment, for various applications. The outer lip of waste Turbo jourdani (Turbinidae) shells, a marine snail, was utilized as a raw material for the production of a porous calcium oxide (CaO) catalyst for biodiesel (as fatty acid methyl esters; FAME) production via transesterification of palm oil and methanol. The outer lip of the shell was calcined at 900 °C for 5 h to fully convert the shell (aragonite form of calcium carbonate) into CaO with a porous structure, as characterized and confirmed by thermogravimetric, X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy analyses. Three key reaction parameters: catalyst concentration, methanol: oil molar ratio and reaction time were optimized in terms of maximizing the oil to FAME conversion level. The best conditions were found to be a catalyst concentration of 10 wt%, a 3:1 methanol: oil molar ratio and a 7 h reaction time to give a >99% oil to FAME conversion level. Evaluation of the reusability of the catalyst revealed that its efficiency decreased with each sequential use but that a >90% conversion level was still obtained after eight sequential uses before it then declined markedly.

Partial hydrogenation of soybean oil-derived fatty acid methyl esters was studied using MCM-41 mesoporous silica-supported Pd-Pt bimetallic catalysts with tunable porosity under mild reaction conditions (100 °C, 0.4 MPa H2, 4 h). This process produced partially hydrogenated fatty acid methyl esters (H-FAME) as a new type of high-quality biodiesel fuel enriched in monounsaturated fatty acid methyl esters (mono-FAME), which is a potential source for formulating high blends of biodiesel fuel with petrodiesel. MCM-41 supports with various structural properties and morphologies were synthesized by self-assembly with different amounts of ammonia solution as a mineralizing agent. Bimetallic Pd-Pt nanoparticles with a Pd/Pt atomic ratio of 4 were stepwise impregnated on three MCM-41 supports, resulting in a series of Pd-Pt/MCM-41 bimetallic catalysts with tunable porosity (0.89–1.79 cm3 g−1), average pore size (3.2–8.5 nm), and particle size (0.12–0.62 μm). The Pd-Pt/MCM-41 catalyst prepared with the least amount of ammonia produced the best partial hydrogenation conversion of polyunsaturated FAME into mono-FAME, ascribed to nano-aggregation resulting in a dual-pore system containing large pores for fast molecular diffusion; a high turnover frequency (1920 h−1), larger k1 rate constant (0.60 gcat−1h−1), and smaller k2 rate constant (0.37 gcat−1h−1) were obtained. Furthermore, this Pd-Pt/MCM-41 catalyst exhibited excellent sulfur resistance in the synthesis of H-FAME, even though the feedstocks contained approximately 5 ppm of sulfur contaminates. These results demonstrate that the sulfur-resistant Pd-Pt/MCM-41 bimetallic catalysts with stable and dual pore system are beneficial for obtaining higher quality BDF to reduce our reliance on fossil fuels.

Zr-SBA-15 materials have been successfully synthesized using the direct synthesis method in self-generated acidic conditions. The diffuse reflectance UV-visible (DRUV-vis) spectra and X-ray photoelectron spectroscopy (XPS) results revealed that most of the zirconium species could be incorporated into silica framework. No agglomeration of Zr species was detected in the silica framework and at the extra-framework. Nevertheless, the continuous diminution of BET surface area, total pore volume, and pore width with increase in Zr/Si molar ratios was distinctly observed, which resulted from the deposition of some tiny and well-dispersed Zr species at the inner pore walls and/or external surface areas. The Zr incorporation also resulted in the augmentation of the microporous characteristics of all materials. The CO 2 adsorption measurement was performed under ambient conditions (25 °C and 1 bar) in order to meet the broad needs of industry and household. The largest amount of CO 2 uptake was demonstrated by 0.03 Zr-SBA-15 at around 0.68 mmol/g (29.92 mg/g). The CO 2 adsorption capability of these materials correlated considerably with their textural properties, particularly microporous volume (V Micro ).

Energy- and cost efficient processes are desirable for the large scale production of fatty acid methyl ester (FAME) for fuel applications. This work reports the utilization of Sr loaded bovine bone as effective and reusable catalyst for FAME production at low temperatures (30–65 °C), in high yields (>90%). Loading of Sr(NO3)2 into bovine bone (as a porous support) followed by calcination (500–1100 °C) affords a series of catalytically active materials. Material calcined at 750 °C (denoted as SrC750) gives optimum performance, with very high FAME yields (96.5%) after 1 h at 65 °C, and can be reused up to 10 times without yield decrease or need for regeneration. High yields of FAME (>93%) are also achieved at ambient temperature (30 °C) using SrC750, with products meeting ASTM 6751 and EN 14214 requirements suggesting their applicability as fuels in diesel engines.

The effect of the pore size of Pd/MCM-41 on the catalytic activity and selectivity in partial hydrogenation of canola-oil-derived biodiesel was studied under mild reaction conditions. The catalysts with different pore sizes were obtained by varying the amount of aqueous ammonia added during the synthesis: Pd/MCM-41-a8, Pd/MCM-41-a5, and Pd/MCM-41-a3 with average pore diameters of 3.72, 3.99, and 7.55 nm, respectively. The supports and supported Pd catalysts were characterized by Brunauer–Emmett–Teller surface area analysis, X-ray powder diffraction, transmission electron microscopy, CO pulse chemisorption, and temperature-programmed desorption of ammonia. The highest hydrogenation activity was found for the largest pore catalyst, Pd/MCM-41-a3, as presented in term of the turnover frequency (TOF), whereas Pd/MCM41-a8 and Pd/MCM-41-a5 provided higher selectivity toward cis-monounsaturated fatty acid methyl ester (FAME), which was attributed to their limited pore dimension. The correlation between the cataly...

Hydrogen production by oxidative steam reforming of methanol (OSRM) or autothermal steam reforming of methanol (ASRM) was investigated over Cu-loaded mesoporous CeO2 and Cu-loaded mesoporous CeO2–ZrO2 catalysts, synthesized via a nanocasting process using MCM-48 as a hard template, followed by a deposition–precipitation technique. Various Cu contents were loaded on the mesoporous CeO2 and CeO2–ZrO2 supports. The fresh and spent catalysts were characterized by N2 adsorption–desorption, X-ray diffraction, temperature-programmed oxidation, and X-ray photoelectron spectroscopy. The ASRM results showed that 9 wt% Cu loading onto mesoporous CeO2 and CeO2–ZrO2 provided the best catalytic performance with 100% methanol conversion and 60% H2 yield at 350° and 300 °C, respectively. Furthermore, the time-on-stream stability testing of the 9 wt% Cu loading catalyst was at 168 h, and the CO selectivity of these two catalysts indicated that the addition of ZrO2 into the catalyst reduced the CO selectivity during the ASRM process.

Napier grass, Pennisetum purpureum cv. Pakchong 1, was pretreated in an ionic liquid mixture through microwave irradiation. To improve the fermentable sugar yield, an acid catalyzed aqueous ionic liquid pretreatment was applied to maximize the total sugar conversion of pretreated Napier grass. Additionally, to optimize the fermentable sugar yield, experiments were carried out employing response surface methodology (RSM). The study showed that a maximum fermentable sugar concentration of 15.72 g/L could be predicted from the model when Napier grass was pretreated by 1-ethyl-3-methylimidazolium acetate ([EMIM] [OAc]) 50% (v/v) aqueous mixture combined with 1.287% (v/v) acetic acid at a microwave pretreatment temperature and time of 147 °C and 76 min, respectively. The experiments confirmed that the maximum sugar concentration obtained from acidic aqueous ionic liquid pretreatment were 14.38 g/L under the optimal conditions. The results from the Fourier transmission infrared spectroscopic showed that an acid catalyzed aqueous ionic liquid pretreatment removed large fractions of lignin.

Copper (Cu) supported on mesoporous (MSP) ceria catalysts were prepared by deposition-precipitation (DP) method for the preferential CO oxidation of CO in a H2-rich stream (CO-PROX). A MSP ceria support with a high surface area of 293 m2/g and ordered structure was synthesized by a nanocasting process using MCM-48 as template. All copper-MSP ceria catalysts show high dispersion of Cu and still maintain the fluorite structure of MSP ceria. Moreover, TEM imaging confirmed the three dimensional and long-range ordered pore structure of the Cu-catalysts. The reduction temperature of the Cu-catalysts decreases compared to pure MSP ceria and the reduction of Ce4+ to Ce3+ decreases with increasing copper content. An MSP ceria catalyst with 7 wt% Cu loading (7Cu/MSP ceria) shows the highest activity with high stability for over 48 h in various feed components, making it attractive for use as a catalyst in purification of hydrogen.

CO 2 gasification of torrefied forest residues (birch and spruce branches) was investigated by means of a thermogravimetric analyser operated non-isothermally (400–1273 K) and isothermally (1123 K) under the kinetic regime, followed by kinetic analyses assuming different models. For the non-isothermal gasification, the distributed activation energy model (DAEM) with four or five pseudo-components was assumed. It is found that the severity level of torrefaction had great influences on gasification behaviour as well as devolatilization step. The activation energy of non-isothermal gasification step of three samples varied in the range of 260–290 kJ/mol. The char reactivity decreased with increased torrefaction temperature. For the isothermal gasification, the random pore model (RPM), shrinking core model (SCM), and homogeneous model (HM) were tested. The result has confirmed the trend of decrease in char reactivity with increased torrefaction temperature observed from the non-isothermal gasification. However, different trends in char reactivity due to different wood types were observed by the two methods of gasification.

In this work, three preparation methods (an incipient wetness impregnation on Mg–Al hydrotalcite, co-precipitation (CP) and double-step-co-precipitation) were employed to prepare Cu-based Mg–Al layered double oxides for the water–gas shift reaction. The Cu 0.15 Mg 3 Al-CP300 catalyst formed by CP had a higher reducing the CO level with a lower H 2 consumption. Varying Mg/Al molar ratios from 1 to 4, the Cu 0.15 Mg 3 Al-CP300 showed the lowest reduction temperature and highest catalytic activity. Increasing the calcination temperature from 300 °C to 500 °C resulted in a higher CO conversion level. Increasing the Cu/(Cu + Mg + Al) molar ratio from 0.15 to 0.30 reduced the crystallite sizes of the periclase phase with a markedly enhanced catalytic activity at temperatures below 350 °C. No marked deactivation of the Cu 0.30 Mg 3 Al-CP500 catalyst was found over a period test even though adding CO 2 in the feed. After regeneration, the catalytic activity of the spent catalyst was the same as the fresh catalyst.

The catalytic performance of Pd, Pt, and Ni supported on SiO2 catalysts was investigated for partial hydrogenation of soybean methyl esters, in terms of FAME composition and biodiesel properties, especially oxidative stability and cold flow properties. The effect of Mg modifier over SiO2-supported catalysts on cis-trans selectivity of polyunsaturated FAMEs was also examined. The catalytic testing was performed under reaction conditions of 4 bar hydrogen pressure and 80–120 °C. Hydrogenation activity was presented by turnover frequency (TOF) of diunsaturated fatty acid (C18:2) within 4 h of the reaction time. The highest TOF was obtained over Pd catalysts, while the lowest TOF was obtained from Ni catalysts. At high reaction temperature conditions showed a large amount of cis-monounsaturated fatty acid (cis-C18:1); however, it exhibited a large amount of trans-monounsaturated fatty acid (trans-C18:1) which has a negative impact on biodiesel properties. The XPS revealed that the introduction of Mg leads to a strong metal–support interaction caused by electron transfer from the support to the metal, which decreased trans-C18:1 formation and presented the higher oxidative stability than the catalysts without Mg modifier.

Corncob is a potential feedstock in Thailand that can be used for fermentable sugar production through dilute sulfuric acid pretreatment and enzymatic hydrolysis. To recover high amounts of monomeric sugars from corncob, the sulfuric pretreatment conditions were optimized by using response surface methodology with three independent variables: sulfuric acid concentration, temperature, and time. The highest response of total sugars, 48.84 g/L, was found at 122.78°C, 4.65 min, and 2.82% (v/v) H2SO4. With these conditions, total sugars from the confirmation experiment were 46.29 g/L, with 5.51% error from the predicted value. The hydrolysate was used as a substrate for acetone-butanol-ethanol fermentation to evaluate its potential for microbial growth. The simultaneous saccharification and fermentation (SSF) showed that C. beijerinckii TISTR 1461 can generate acetone-butanol-ethanol products at 11.64 g/L (5.29 g/L acetone, 6.26 g/L butanol, and 0.09 g/L ethanol) instantly using sugars from the hydrolysed corncob with Novozymes 50013 cellulase enzyme without an overliming process.

Tilapia lake virus (TiLV) causes an emerging viral disease associated with high mortality and economic damage in tilapia farming around the world. The use of probiotics in aquaculture has been suggested as an alternative to antibiotics and drugs to reduce the negative impact of bacterial and viral infections. In this study, we investigate the effect of probiotic Bacillus spp. supplementation on mortality, viral load, and expression of immune-related genes in red hybrid tilapia (Oreochromis spp.) upon TiLV infection. Fish were divided into three groups, and fed with: control diet, 0.5% probiotics-supplemented diet, and 1% probiotics-supplemented diet. After 21 days of experimental feeding, the three groups were infected with TiLV and monitored for mortality and growth performances, while organs were sampled at different time points to measure viral load and the transcription modulation of immune response markers. No significant difference was found among the groups in terms of weight gain (WG), average daily gain (ADG), feed efficiency (FE), or feed conversion ratio (FCR). A lower cumulative mortality was retrieved from fish fed 0.5% and 1% probiotics (25% and 24%, respectively), compared to the control group (32%). Moreover, fish fed with 1% probiotic diet had a significantly lower viral load, than those fed with 0.5% probiotic and control diet at 5, 6, 9, and 12 days post infection-challenge (dpc). The expression patterns of immune-related genes, including il-8 (also known as CXCL8), ifn-&gamma, irf-3, mx, rsad-2 (also known as VIPERIN) showed significant upregulation upon probiotic treatment during the peak of TiLV pathogenesis (between 9 and 12 dpc) and during most of the study period in fish fed with 1% probiotics-supplemented diet. Taken together, these findings indicate that dietary supplementation using Bacillus spp. probiotics may have beneficial effects to strengthen tilapia immunity and resistance against TiLV infections. Therefore, probiotic treatments may be preventively administered to reduce losses caused by this emerging viral infection in tilapia aquaculture.

Facile synthesis of superficial Pd nanoparticles supported on carbonaceous SBA-15 (denoted as Pd/@SBA-15) as a new hydrotreating catalyst with enhanced activity and sulfur tolerance was accomplished for the production of partially hydrogenated fatty acid methyl esters (H-FAME), a high-quality biodiesel fuel enriched in monosaturated fatty acid methyl esters (mono-FAME) that can be used in high blends. Characterization, especially high-resolution electron microscopes and temperature-programmed techniques, indicated that the Pd nanoparticles (∼7 nm) formed spontaneously at the superficial area of carbonaceous SBA-15 with a hydrophobic surface and low acidity. In the synthesis of H-FAME using commercial palm oil-derived biodiesel fuel as a feedstock under mild conditions (

Partial hydrogenation of soybean oil-derived fatty acid methyl esters (FAMEs) was performed to improve oxidative stability of biodiesel. The reaction was tested in a semi-batch reactor at 100 °C, 0.4 MPa. The effect of Pd particle size on activity and cis-trans selectivity was investigated over SiO2- and MCM-41-supported Pd catalysts, with different Pd loadings (0.5 and 1 wt.%). For Pd/SiO2 catalysts with relatively large Pd particle sizes (6.1–7.8 nm), the adsorption of polyunsaturated C18:2 and C18:3 FAMEs was promoted on the flat metal surface, providing 2- to 3-fold higher turnover frequency (TOF) compared with Pd/MCM-41 catalysts. In contrast, the Pd/MCM-41 catalysts with relatively small Pd particle sizes (2.7–4.0 nm), showed higher selectivity towards the desired monounsaturated C18:1 FAMEs due to lower affinity of isolated double bond (presented in C18:1) on the Pd surface. In addition, selectivity towards the desired cis-C18:1 FAMEs was found to be highly sensitive to Pd particle size. The 0.5Pd/MCM-41 catalyst with small Pd particle size (2.7 nm), provided high cis-C18:1 selectivity, resulting in a biodiesel with better cold flow property compared with the trans-isomers. With partial hydrogenation over the prepared Pd catalysts, biodiesel with significantly improved oxidative stability (>10 h) could be obtained.

The adsorption of wastewater from various industrial sources is important and one of the dangerous challenges the environment. This study focuses on the investigation of the efficiency of zinc ions adsorption by using activated carbon in synthetic wastewater. Activated carbon was prepared from palm kernel shells that were obtained from Songkhla province, Thailand. Activated carbon was prepared from palm kernel shells containing sodium chloride as a catalyst at the ratio 1:0, 1:1 and 1:2 (w/w), respectively. Activated carbon was calcined at 700 °C for 2 h. Next, it was washed with hot distillate water until pH = 7. After that, it was dried at 105 °C for 24 h. Iodine number was analyzed by using CHNS/O analyzer. The concentration of solution was examined by using atomic absorption spectrophotometer (AAS). The prepared activated carbon was characterized by thermogravimetric analysis (TGA), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), X-ray fluorescence spectrophotometer (XRF), X-ray diffractometry (XRD) and Fourier-transform infrared spectroscopy (FTIR). For the pure activated carbon, it was noteworthy that the major components were O (37.25%), N (30.95%) and C (26.54%), whilst a minor content was H (2.23%), C (1.73%) and Si (0.76%). This result was strongly consistent with the XRF analysis. The ratio of activated carbon to sodium chloride 1:2 (w/w) exhibited the highest iodine number (180.95±10.82 mg/g). The factors of adsorption including initial concentration (20-150 ppm) and adsorption time (2-10 h.) The result showed that the optimum conditions of adsorption containing concentration were 65 ppm and adsorption time was 10 h. The efficiency of adsorption was 69.73 %.