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1.
Data Brief ; 54: 110375, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623543

RESUMO

The Response Surface Methodology (RSM) was employed to examine the impact of the pumping system in a photovoltaic solar water pumping system, while operating under ideal conditions. The input parameters for optimizing the pump performance of the PV water pump include three parameters: Solar irradiance (550-950, W/m2), temperature (30-45, °C), and voltage (420-540, V). The experimental values of PV water pump efficiency showed that the efficiency of PV water pumps was in the range of 55.24-80.80% of the experiment. At a solar irradiance of 750 W/m2, a voltage of 480 V and a temperature of 37.5 °C shows the maximum efficiency of the solar PV water pump systems was 80.80% under optimal conditions. This work demonstrates the potential of solar water pumps as a reliable, cost-effective, and environmentally friendly solution to support agriculture in remote areas. In addition, the costs and economic parameters of solar photovoltaic water pumps and conventional systems were compared by the social return on investment (SROI) evaluation. This indicates that sales are profitable or create social value that benefits society and local stakeholders in remote areas. This work demonstrates the potential of solar water pumps as a reliable, cost-effective, and environmentally friendly solution to support agriculture in remote areas.

2.
Data Brief ; 49: 109370, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37483884

RESUMO

The banana industry in Thailand holds immense potential, driven by favorable growing conditions, robust domestic consumption, and active participation in the export market. Solar dryers have the potential to revolutionize fruit processing by providing a sustainable, cost-effective, and nutritionally rich solution. This research aims to optimize the greenhouse solar drying process for bananas using response surface methodology. The specific variables under investigation are drying temperature and drying time. A designed greenhouse solar dryer, tailored for commercial use in the target area, was employed for the experiment. Statistical analysis and response surface methodology were utilized to evaluate the effects of the experimental variables on two key outputs: moisture content and color change of the dried banana product. The findings of this study contribute to a deeper understanding of the potential of solar drying in the context of banana processing. The research outcomes provide valuable insights for optimizing the solar drying process, thereby facilitating the development of the banana industry and its applicability.

3.
Antibiotics (Basel) ; 12(6)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37370344

RESUMO

Copious use of antibiotics in aquaculture farming systems has resulted in surface water contamination in some countries. Our objective was to develop a slow-release oxidant that could be used in situ to reduce antibiotic concentrations in discharges from aquaculture lagoons. We accomplished this by generating a slow-release permanganate (SR-MnO4-) that was composed of a biodegradable wax and a phosphate-based dispersing agent. Sulfadimethoxine (SDM) and its synergistic antibiotics were used as representative surrogates. Kinetic experiments verified that the antibiotic-MnO4- reactions were first-order with respect to MnO4- and initial antibiotic concentration (second-order rates: 0.056-0.128 s-1 M-1). A series of batch experiments showed that solution pH, water matrices, and humic acids impacted SDM degradation efficiency. Degradation plateaus were observed in the presence of humic acids (>20 mgL-1), which caused greater MnO2 production. A mixture of KMnO4/beeswax/paraffin (SRB) at a ratio of 11.5:4:1 (w/w) was better for biodegradability and the continual release of MnO4-, but MnO2 formation altered release patterns. Adding tetrapotassium pyrophosphate (TKPP) into the composite resulted in delaying MnO2 aggregation and increased SDM removal efficiency to 90% due to the increased oxidative sites on the MnO2 particle surface. The MnO4- release data fit the Siepmann-Peppas model over the long term (t < 48 d) while a Higuchi model provided a better fit for shorter timeframes (t < 8 d). Our flow-through discharge tank system using SRB with TKPP continually reduced the SDM concentration in both DI water and lagoon wastewater. These results support SRB with TKPP as an effective composite for treating antibiotic residues in aquaculture discharge water.

4.
ACS Omega ; 8(43): 40433-40441, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37929142

RESUMO

Agricultural waste is an alternative source for plant growth regulator biosynthesis by microorganisms. Actinobacteria are important soil microbes that significantly impact the soil as plant growth-promoting rhizobacteria and biofertilizers. This study focused on developing low-cost medium based on bagasse to improve indole-3-acetic acid (IAA) production by Streptomyces lavenduligriseus BS50-1 using a response surface methodology (RSM). Among 34 actinobacterial strains, S. lavenduligriseus BS50-1 produced the highest IAA level within the selected medium. An RSM based on a central composite design optimized the appropriate nutrients for IAA production. Thus, glucose hydrolysate and l-tryptophan at concentrations of 3.55 and 5.0 g/L, respectively, were the optimal factors that improved IAA production from 37.50 to 159.47 µg/mL within 168 h. This study reported a potential application of leftover bagasse as the raw material for cultivating actinobacteria, which efficiently produce IAA to promote plant growth.

5.
Antibiotics (Basel) ; 11(9)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36140040

RESUMO

Excessive antibiotic use in veterinary applications has resulted in water contamination and potentially poses a serious threat to aquatic environments and human health. The objective of the current study was to quantify carbonized leonardite (cLND) adsorption capabilities to remove sulfamethoxazole (SMX)- and enrofloxacin (ENR)-contaminated water and to determine the microbial activity of ENR residuals on cLND following adsorption. The cLND samples prepared at 450 °C and 850 °C (cLND450 and cLND550, respectively) were evaluated for structural and physical characteristics and adsorption capabilities based on adsorption kinetics and isotherm studies. The low pyrolysis temperature of cLND resulted in a heterogeneous surface that was abundant in both hydrophobic and hydrophilic functional groups. SMX and ENR adsorption were best described using a pseudo-second-order rate expression. The SMX and ENR adsorption equilibrium data on cLND450 and cLND550 revealed their better compliance with a Langmuir isotherm than with four other models based on 2.3-fold higher values of qmENR than qmSMX. Under the presence of the environmental interference, the electrostatic interaction was the main contributing factor to the adsorption capability. Microbial activity experiments based on the growth of Staphylococcus aureus ATCC 25923 revealed that cLND could successfully adsorb and subsequently retain the adsorbed antibiotic on the cLND surface. This study demonstrated the potential of cLND550 as a suitable low-cost adsorbent for the highly efficient removal of antibiotics from water.

6.
ACS Omega ; 6(8): 5389-5398, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33681578

RESUMO

Organosolv fractionation is a promising approach for the separation of lignocellulosic components in integrated biorefineries where each component can be fully valorized into valuable platform chemicals and biofuels. In this study, microwave-accelerated organosolv fractionation was developed for the modification of lignocellulosic fractionation of rice husk. The fractionation condition was optimized for 1 h with the microwave irradiation at 300 W using a ternary solvent mixture composed of 24%:32%:44% water/ethanol/methyl isobutyl ketone. The effects of mineral acids (HCl, H3PO4, and H2SO4) and heterogeneous acid promoters (HCl, H3PO4, and H2SO4 impregnated over activated carbon) on the efficiency and selectivity of product yields (i.e., glucan, hemicellulose-derived products, and lignin) were also investigated. It was found that the use of H3PO4-activated carbon as the promoter showed superior performance on the fractionation of rice husk components, resulting in 88.8% recovery of cellulose, with 63.8% purity in the solid phase, whereas the recovery of hemicellulose (66.4%) with the lowest formation of furan and 5-hydroxymethyl furfural and lignin (81.0%) without sugar cross-contamination was obtained in the aqueous ethanol phase and organic phase, respectively. In addition, the morphology structure of fractionated rice husk presented 2.6-fold higher surface area (5.4 m2/g) of cellulose-enriched fraction in comparison with the native rice husk (2.1 m2/g), indicating the improvement of enzyme accessibility. Besides, the chemical changes of isolated lignin were also investigated by Fourier-transform infrared spectroscopy. This work gives pieces of information into the efficiencies of the microwave strategy as a climate neighborly elective fractionation method for this serious starting material in the biotreatment facility business.

7.
RSC Adv ; 11(43): 26773-26784, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35480031

RESUMO

Conversion of lignocellulosic residue to bioenergy and biofuel is a promising platform for global sustainability. Fractionation is an initial step for isolating lignocellulosic components for subsequent valorization. The aim of this research is to develop the solvothermal fractionation of sugarcane bagasse to produce high purity lignin. The physio-chemical structure of isolated lignin from this process was determined. In this study, a central composite design-based response surface methodology (RSM) was used to optimize an acid promoter for isolating lignin from sugarcane bagasse using a solvothermal fractionation process. The reaction was carried out with sulfuric acid, at a concentration of 0.01-0.02 M and a reaction temperature of 180-200 °C for 30-90 min. The optimal conditions for the experiment were obtained at the acid concentration of 0.02 M with a temperature of 200 °C for 90 min in methyl isobutyl ketone (MIBK)/methanol/water (35% : 25% : 40% v/v%). The results showed that 88% of lignin removal was done in the solid phase, while 87% of lignin recovery was conducted in the organic phase. Furthermore, the changes in the physico-chemical characteristics of solid residue and lignin recovery were analyzed using various techniques. GPC analysis of recovered lignin from the organic fraction showed a lower M w (1374 g mol-1) and polydispersity index (1.75) compared to commercial organosolv lignin. The major lignin degradation temperature of commercial organosolv lignin was estimated to be 410 °C, whereas BGL showed two main degradations at 291 °C and 437 °C, which could point to potential relationships with the degradation of ß-O-4 cross-links. The results indicated that recovered lignin was mostly cross-linked by ß-O-4 cross-links. In addition, Py-GC/MS and 2D HSQC NMR gave more information regarding the compositional and structural features of recovered lignin. The development of the sulfuric acid catalyzed solvothermal process in this study provides efficient extraction of high-value organosolv lignin from sugarcane bagasse and the production of recovered lignin in the organic phase with low contamination from other contents. The lignin characteristic data can contribute to the development of lignin valorization in value-added applications.

8.
Front Chem ; 9: 697237, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422761

RESUMO

Fractionation of lignocellulosic is a fundamental step in the production of value-added biobased products. This work proposes an initiative to efficiently extract lignin from the corn stover using a single-step solvothermal fractionation in the presence of an acid promoter (H2SO4). The organic solvent mixture used consists of ethyl acetate, ethanol, and water at a ratio of 30: 25:45 (v/v), respectively. H2SO4 was utilized as a promoter to improve the performance and selectivity of lignin removal from the solid phase and to increase the amount of recovered lignin in the organic phase. The optimal conditions for this extraction, based on response surface methodology (RSM), are a temperature of 180°C maintained for 49.1 min at an H2SO4 concentration of 0.08 M. The optimal conditions show an efficient reaction with 98.0% cellulose yield and 75.0% lignin removal corresponding to 72.9% lignin recovery. In addition, the extracted lignin fractions, chemical composition, and structural features were investigated using Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis, and two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance spectroscopy (2D-HSQC NMR). The results indicate that the recovered lignin primarily contains a ß-O-4 linking motif based on 2D-HSQC spectra. In addition, new C-C inter-unit linkages (i.e., ß-ß, and ß-5) are not formed in the recovered lignin during H2SO4-catalyzed solvothermal pretreatment. This work facilitates effective valorization of lignin into value-added chemicals and fuels.

9.
ACS Omega ; 5(46): 29872-29881, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33251422

RESUMO

Lignocellulose is a promising raw material for the production of second-generation biofuels. In this study, the effects of acid-catalyzed liquid hot water (LHW) on pretreatment of corn stover (CS) for subsequent hydrolysis and conversion to ethanol were studied. The effects of reaction temperature, acid concentration, and residence time on glucose yield were evaluated using a response surface methodology. The optimal condition was 162.4 °C for 29.5 min with 0.45% v/v of sulfuric acid, leading to the maximum glucose yield of 91.05% from enzymatic hydrolysis of the cellulose-enriched fraction. Conversion of the solid fraction to ethanol by simultaneous saccharification and fermentation resulted in a theoretical ethanol yield of 93.91% based on digestible glucose. Scanning electron microscopy revealed disruption on the microstructure of the pretreated CS. Increases of crystallinity index and surface area of the pretreated biomass were observed along with alteration in the functional group profiles, as demonstrated by Fourier transform infrared spectroscopy. This work provides an insight into the effects of LHW on the enzymatic susceptibility and modification of the physicochemical properties of CS for further application on bioethanol production in biorefinery.

10.
Appl Biochem Biotechnol ; 184(2): 432-443, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28721652

RESUMO

Liquid hot water (LHW) pretreatment is an efficient chemical-free strategy for enhancing enzymatic digestibility of lignocellulosic biomass for conversion to fuels and chemicals in biorefinery. In this study, effects of LHW on removals of hemicelluloses and lignin from corncobs were studied under varying reaction conditions. LHW pretreatment at 160 °C for 10 min promoted the highest levels of hemicellulose solubilization into the liquid phase, resulting into the maximized pentose yield of 58.8% in the liquid and more than 60% removal of lignin from the solid, with 73.1% glucose recovery from enzymatic hydrolysis of the pretreated biomass using 10 FPU/g Celluclast™. This led to the maximal glucose and pentose recoveries of 81.9 and 71.2%, respectively, when combining sugars from the liquid phase from LHW and hydrolysis of the solid. Scanning electron microscopy revealed disruption of the intact biomass structure allowing increasing enzyme's accessibility to the cellulose microfibers which showed higher crystallinity index compared to the native biomass as shown by x-ray diffraction with a marked increase in surface area as revealed by BET measurement. The work provides an insight into effects of LHW on modification of physicochemical properties of corncobs and an efficient approach for its processing in biorefinery industry.


Assuntos
Biomassa , Celulases/química , Proteínas Fúngicas/química , Temperatura Alta , Lignina/química , Água/química , Hidrólise
11.
Bioresour Technol ; 171: 29-36, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25181697

RESUMO

In this study, effects of homogeneous acid and alkali promoters on efficiency and selectivity of LHW pretreatment of rice straw were studied. The presences of acid (0.25%v/v H2SO4, HCl, H3PO4, and oxalic acid) and alkali (0.25 w/v NaOH) efficiently promoted hydrolysis of hemicellulose, improved enzymatic digestibility of the solids, and lower the required LHW temperature. Oxalic acid was a superior promoter under the optimal LHW conditions at 160 °C, leading to the highest glucose yield from enzymatic hydrolysis (84.2%) and the lowest formation of furans. Combined with hydrolyzed glucose in the liquid, this resulted in the maximal 91.6% glucose recovery from the native rice straw. This was related to changes in surface area and crystallinity of pretreated biomass. The results showed efficiency of external promoters on increasing sugar recovery and saving energy in LHW pretreatment.


Assuntos
Biocombustíveis , Lignina/química , Oryza/química , Ácido Oxálico/química , Caules de Planta/química , Hidróxido de Sódio/química , Temperatura Alta , Ácido Clorídrico/química , Ácidos Fosfóricos/química , Pressão , Ácidos Sulfúricos/química , Água/química
12.
Appl Biochem Biotechnol ; 170(8): 1982-95, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23807488

RESUMO

Pretreatment is an essential step in biorefineries for improving digestibility of recalcitrant agricultural feedstocks prior to enzymatic hydrolysis to composite sugars, which can be further converted to fuels and chemicals. In this study, autohydrolysis by compressed liquid hot water (LHW) pretreatment of various tropical agricultural residues including sugarcane bagasse (BG), rice straw (RS), corn stover (CS), and empty palm fruit bunch (EPFB) was investigated. It was found that LHW pretreatment at 200 °C for 5-20 min resulted in high levels of hemicellulose solubilization into the liquid phase and marked improvement on enzymatic digestibility of the solid cellulose-enriched residues. The maximal yields of glucose and pentose were 409.8-482.7 mg/g and 81.1-174.0 mg/g of pretreated substrates, respectively. Comparative analysis based on severity factor showed varying susceptibility of biomass to LHW in the order of BG> RS> CS> EPFB. Structural analysis revealed surface modification of the pretreated biomass along with an increase in crystallinity index. Overall, 75.7-82.3 % yield of glucose and 27.4-42.4 % yield of pentose from the dried native biomass was recovered in the pretreated solid residues, while 18.3-29.7 % of pentoses were recovered in the liquid phase with dehydration by-product concentration under the threshold for ethanologens. The results suggest the potential of LHW as an efficient pretreatment strategy for implementation in biorefineries operated using various seasonal agricultural feedstocks.


Assuntos
Carboidratos/síntese química , Produtos Agrícolas/química , Resíduos Industriais/prevenção & controle , Complexos Multienzimáticos/química , Clima Tropical , Água/química , Agricultura/métodos , Temperatura Alta , Hidrólise , Resíduos Industriais/análise , Pressão , Soluções
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