scholarly journals Use of carbonized corn cob biomass to reduce acidity of residual frying oil

2021 ◽  
Vol 43 ◽  
pp. e51303
Author(s):  
Aline Bavaresco ◽  
Jhessica Marchini Fonseca ◽  
Fabiano Bisinella Scheufele ◽  
Camila da Silva ◽  
Joel Gustavo Teleken
Keyword(s):  
Adsorption Kinetics ◽  
Thermal Energy ◽  
Solid Fuel ◽  
Active Sites ◽  
Biodiesel Production ◽  
Corn Cob ◽  
A Value ◽  
Calorific Power ◽  
Cob Biomass ◽  
Molecular Sieving

The objective of this work was to evaluate the ability of CCC as an adsorbent material for the acidity removal of RFO, aiming at the application of the oil in biodiesel production. For that, a RCCD was used for FFA removal by applying the CCC and CAC for comparative purposes. In the RCCD removal assays the effect of the Temperature, Agitation and Mass factors were assessed over acidity removal of the oil. Under the best conditions from RCCD, an evaluation of adsorption kinetics was performed, wherein it was observed the equilibrium was reached within 4 h, for the CCC. Also, the influence of the adsorbent dosage was performed. It was verified that 4 g was sufficient to allow the system to reach the maximum FFA removal. Overall, the CCC presented results approximately twice as high than those obtained by the CAC, mainly due to the pore size distribution which led to a “molecular sieving effect” for the CCC adsorbent. It allowed the major diffusion of the FFA molecules inside its narrow-distributed pores, whereas the CAC with a wider pore distribution (up to 260 Å) resulted in the larger molecules competition for the active sites inside the porous structure. The adsorbents’ characterization also evidenced that CCC adsorbent presented a higher content of oxygenated groups in its surface which acted as potential active sites for the FFA molecules resulting in an enhanced adsorbent-adsorbate affinity. Lastly, the wastes generated in the adsorption experiments, were evaluated as to their calorific power resulting in a value of 31,933 J g-1, suggesting that it could be further used for energetic purposes, such as a solid fuel for boilers and furnaces to generate thermal energy. Based on these results, the CCC stands out as a promising material for RFO acidity removal.

Efficient Production of Biodiesel Catalyzed by Acidic Nanoporous Carbon Materials：A Review

2020 ◽  
Vol 16 ◽  
Author(s):  
Anping Wang ◽  
Heng Zhang ◽  
Hu Li ◽  
Song Yang
Keyword(s):  
Pore Structure ◽  
Active Sites ◽  
Catalytic Performance ◽  
Nanoporous Carbon ◽  
Biodiesel Production ◽  
Efficient Production ◽  
Fossil Energy ◽  
Catalytic Materials ◽  
High Acid ◽  
Carbon Based

Background: With the gradual decrease of fossil energy, the development of alternatives to fossil energy has attracted more and more attention. Biodiesel is considered to be the most potent alternative to fossil energy, mainly due to its green, renewable and biodegradable advantages. The stable, efficient and reusable catalysts are undoubtedly the most critical in the preparation of biodiesel. Among them, nanoporous carbon-based acidic materials are very important biodiesel catalysts. Objective: The latest advances of acidic nanoporous carbon catalysts in biodiesel production was reviewed. Methods: Biodiesel is mainly synthesized by esterification and transesterification. Due to the important role of nanoporous carbon-based acidic materials in the catalytic preparation of biodiesel, we focused on the synthesis, physical and chemical properties, catalytic performance and reusability. Results: Acidic catalytic materials have a good catalytic performance for high acid value feedstocks. However, the preparation of biodiesel with acid catalyst requires relatively strict reaction conditions. The application of nanoporous acidic carbon-based materials, due to the support of carbon-based framework, makes the catalyst have good stability and unique pore structure, accelerates the reaction mass transfer speed and accelerates the reaction. Conclusion: Nanoporous carbon-based acidic catalysts have the advantages of suitable pore structure, high active sites, and high stability. In order to make these catalytic processes more efficient, environmentally friendly and low cost, it is an important research direction for the future biodiesel catalysts to develop new catalytic materials with high specific surface area, suitable pore size, high acid density, and excellent performance.

Molecular sieving of small solutes by outer medullary descending vasa recta

1997 ◽  
Vol 272 (5) ◽  
pp. F579-F586 ◽  
Author(s):  
T. L. Pallone ◽  
M. R. Turner
Keyword(s):  
Water Channel ◽  
Fluorescein Isothiocyanate ◽  
Pressure Gradients ◽  
Volume Flux ◽  
Aquaporin 1 ◽  
A Value ◽  
Vasa Recta ◽  
Mathematical Simulations ◽  
Molecular Sieving ◽  
Hydrophilic Solutes

Molecular sieving of small solutes by outer medullary descending vasa recta (OMDVR). Descending vasa recta (DVR) plasma equilibrates with the medullary interstitium by volume efflux (Jv), as well as by influx of solutes. Jv is driven by transmural osmotic pressure gradients due to small hydrophilic solutes (delta pi s), NaCl and urea. DVR endothelium probably contains a "water-only" pathway most likely mediated by the aquaporin-1 (AQP1) water channel. We measured the ability of microperfused OMDVR to concentrate lumenal 22Na and [3H]raffinose when Jv was driven by transmural NaCl gradients. Collectate-to-perfusate ratios of 2 x 10(6) M(r) fluorescein isothiocyanate-labeled dextran volume marker (RDx), 22Na (RNa), and [3H]raffinose (Rraf) were measured in the absence and presence of Jv. During volume efflux (Jv > 0), RDx was 1.37 +/- 0.31. RNa increased from 0.64 +/- 0.03 when Jv = 0 to 0.82 +/- 0.05 when Jv > 0 and Rraf increased from 0.83 +/- 0.03 to 1.13 +/- 0.05: Mathematical simulations predict RNa and Rraf most accurately when the OMDVR reflection coefficient to the tracers is assigned a value near unity. This indicates that the OMDVR wall contains a pathway for osmotic volume flux that excludes small hydrophilic solutes, a behavior consistent with that of aquaporins.

scholarly journals Probing the Catalytic Efficiency of Supported Heteropoly Acids for Esterification: Effect of Weak Catalyst Support Interactions

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Ali Alsalme ◽  
Aliyah A. Alsharif ◽  
Hamda Al-Enizi ◽  
Mujeeb Khan ◽  
Saad G. Alshammari ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Active Sites ◽  
Catalyst Support ◽  
Supported Catalyst ◽  
Catalytic Efficiency ◽  
Biodiesel Production ◽  
Effect Of Temperature ◽  
Heteropoly Acids ◽  
Catalyst Loading ◽  
Esterification Activity

Supported heteropoly acids are an interesting class of solid acid catalysts which possess flexible structure and super acidic properties essentially required for the oil-based biodiesel production. In this study, a series of catalysts containing 25 wt.% of heteropolytungstate (HPW) supported on various clays or SiO2 were prepared, and their catalytic efficiency was evaluated for esterification of acetic acid with heptanol. The as-prepared catalysts were characterized by various techniques including FT-IR spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and BET. The catalytic efficiency of both bulk and supported HPW catalysts for the esterification activity strongly depends on the type of support and amount of catalyst; the bulk HPW catalyst and the catalyst supported by kaolinite with 25 wt.% of HPW exhibited highest activity. In order to study the effect of temperature on conversion, all the catalysts were subjected to different reaction temperatures. It was revealed that esterification activity of both bulk and supported HPW catalysts strongly depends upon the temperature variations of the reaction. Besides, the effect of leaching of active sites on the catalysts performance for biodiesel production was also evaluated by inductively coupled plasma studies (ICP). The kaolinite-supported catalyst (25% HPW/kaolinite) demonstrated higher amount of leaching which is also confirmed by the significant decrease in its catalytic activity when it is used for the second time. However, the higher activity demonstrated by HPW/kaolinite maybe because of some homogeneous reaction indicating a weak catalyst support interaction (WCSI) resulting in the leaching of the catalyst during the test. Furthermore, the effects of other reaction variables such as catalyst loading and reaction time on the conversion of acetic acid were also studied.

scholarly journals Production of biodiesel from babassu oil using methanol-ethanol blends

2018 ◽  
Vol 35 (1) ◽  
pp. 47
Author(s):  
Fernando Carvalho Silva ◽  
Kiany Sirley Brandão Cavalcante ◽  
Hilton Costa Louzeiro ◽  
Katia Regina Marques Moura ◽  
Adeilton Pereira Maciel ◽  
...  
Keyword(s):  
Specific Gravity ◽  
Vegetable Oils ◽  
Castor Oil ◽  
Kinematic Viscosity ◽  
Volume Ratio ◽  
Biodiesel Production ◽  
Mass Yield ◽  
A Value ◽  
Oil Plant ◽  
Ethanol Blends

Maranhão state in Brazil presents a big potential for the cultivation of several oleaginous species, such as babassu, soybean, castor oil plant, etc... These vegetable oils can be transformed into biodiesel by the transesterification reaction in an alkaline medium, using methanol or ethanol. The biodiesel production from a blend of these alcohols is a way of adding the technical and economical advantages of methanol to the environmental advantages of ethanol. The optimized alcohol blend was observed to be a methanol/ethanol volume ratio of 80 % MeOH: 20 % EtOH. The ester content was of 98.70 %, a value higher than the target of the ANP, 96.5 % (m/m), and the biodiesel mass yield was of 95.32 %. This biodiesel fulfills the specifications of moisture, specific gravity, kinematic viscosity and percentages of free alcohols (methanol plus ethanol) and free glycerin.

scholarly journals Multimodular fused acetyl–feruloyl esterases from soil and gut Bacteroidetes improve xylanase depolymerization of recalcitrant biomass

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Cathleen Kmezik ◽  
Cyrielle Bonzom ◽  
Lisbeth Olsson ◽  
Scott Mazurkewich ◽  
Johan Larsbrink
Keyword(s):  
Esterase Activity ◽  
Glycoside Hydrolase ◽  
Full Length ◽  
Glycoside Hydrolases ◽  
Corn Cob ◽  
Biomass Degradation ◽  
Carbohydrate Esterase ◽  
Catalytic Domains ◽  
Cob Biomass ◽  
Carbohydrate Esterases

Abstract Background Plant biomass is an abundant and renewable carbon source that is recalcitrant towards both chemical and biochemical degradation. Xylan is the second most abundant polysaccharide in biomass after cellulose, and it possesses a variety of carbohydrate substitutions and non-carbohydrate decorations which can impede enzymatic degradation by glycoside hydrolases. Carbohydrate esterases are able to cleave the ester-linked decorations and thereby improve the accessibility of the xylan backbone to glycoside hydrolases, thus improving the degradation process. Enzymes comprising multiple catalytic glycoside hydrolase domains on the same polypeptide have previously been shown to exhibit intramolecular synergism during degradation of biomass. Similarly, natively fused carbohydrate esterase domains are encoded by certain bacteria, but whether these enzymes can result in similar synergistic boosts in biomass degradation has not previously been evaluated. Results Two carbohydrate esterases with similar architectures, each comprising two distinct physically linked catalytic domains from families 1 (CE1) and 6 (CE6), were selected from xylan-targeting polysaccharide utilization loci (PULs) encoded by the Bacteroidetes species Bacteroides ovatus and Flavobacterium johnsoniae. The full-length enzymes as well as the individual catalytic domains showed activity on a range of synthetic model substrates, corn cob biomass, and Japanese beechwood biomass, with predominant acetyl esterase activity for the N-terminal CE6 domains and feruloyl esterase activity for the C-terminal CE1 domains. Moreover, several of the enzyme constructs were able to substantially boost the performance of a commercially available xylanase on corn cob biomass (close to twofold) and Japanese beechwood biomass (up to 20-fold). Interestingly, a significant improvement in xylanase biomass degradation was observed following addition of the full-length multidomain enzyme from B. ovatus versus the addition of its two separated single domains, indicating an intramolecular synergy between the esterase domains. Despite high sequence similarities between the esterase domains from B. ovatus and F. johnsoniae, their addition to the xylanolytic reaction led to different degradation patterns. Conclusion We demonstrated that multidomain carbohydrate esterases, targeting the non-carbohydrate decorations on different xylan polysaccharides, can considerably facilitate glycoside hydrolase-mediated hydrolysis of xylan and xylan-rich biomass. Moreover, we demonstrated for the first time a synergistic effect between the two fused catalytic domains of a multidomain carbohydrate esterase.

scholarly journals Probing the pore structure of hierarchical EU-1 zeolites by adsorption of large molecules and through catalytic reaction

2020 ◽  
pp. 174751982093659
Author(s):  
Zaibin Guo ◽  
Wenming Hao ◽  
Jinghong Ma ◽  
Ruifeng Li
Keyword(s):  
Adsorption Kinetics ◽  
Fumed Silica ◽  
Active Sites ◽  
Main Reaction ◽  
Catalytic Transformation ◽  
Pore System ◽  
Large Molecules ◽  
Silicon Source ◽  
Kinetics Of ◽  
And Diffusion

The adsorption of toluene and 1,3,5-trimethylbenzene and the catalytic transformation of 1,3,5-trimethylbenzene are applied as probing approaches to characterize the pore system of hierarchical EU-1 zeolites prepared using organofunctionalized fumed silica as the silicon source. The adsorption and diffusion of toluene and 1,3,5-trimethylbenzene are significantly improved in the hierarchical EU-1 zeolites compared with the conventional microporous EU-1 zeolite. The adsorption kinetics of toluene and 1,3,5-trimethylbenzene suggested that introducing mesopores significantly increases the rate of adsorption and improved the diffusion of large molecules. In the catalytic transformation of 1,3,5-trimethylbenzene, the conversion of 1,3,5-trimethylbenzene on the hierarchical EU-1 zeolites is doubled compared with the conventional microporous EU-1 zeolite, due to the improved diffusion of bulky molecules and enhanced accessibility of active sites in the hierarchical EU-1 structure. Although isomerization is the main reaction, differences are observed in the product ratios of isomerization to disproportionation between the hierarchical EU-1 zeolites and the microporous counterpart with different times on stream. The transformation of 1,3,5-trimethylbenzene over the hierarchical EU-1 zeolites has a higher isomerization to disproportionation ratio than that over the microporous EU-1 zeolite; this is due to the increased mesoporosity.

Biodiesel Production Using Mixed Solid Catalysts

2013 ◽  
Vol 824 ◽  
pp. 451-458
Author(s):  
A.K. Temu
Keyword(s):  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Biodiesel Production ◽  
Environmentally Benign ◽  
Catalyst Loading ◽  
Yield Data ◽  
Continuous Processes ◽  
Solid Catalysts ◽  
Base Catalysts ◽  
Astm D6751

One of the disadvantages of homogeneous base catalysts in biodiesel production is that they cannot be reused or regenerated because they are consumed in the reaction. Besides, homogeneous catalysed process is not environmentally friendly because a lot of waste water is produced in the separation step. Unlike homogeneous, heterogeneous catalysts are environmentally benign, can be reused and regenerated, and could be operated in continuous processes, thus providing a promising option for biodiesel production. This paper presents catalytic activity of single and mixed solid catalysts in production of biodiesel from palm oil using methanol as well as ethanol at atmospheric pressure. The catalysts used are CaO, K2CO3, Al2O3, and CaO/K2CO3, CaO/Al2O3, K2CO3/Al2O3 mixtures. Results show that methanol is a better reactant with biodiesel yield ranging from 48 to 96.5% while ethanol gives yields ranging from 20 to 95.2%. The yield data for single catalysts range from 20 to 89.2% while that for mixed catalysts range from 52 to 96.5% indicating improvement in the activity by mixing the catalysts. The study also shows that biodiesel yield increases with catalyst loading which emphasizes the need for sufficient number of active sites. The properties of biodiesel produced compares well with ASTM D6751 and EN 14124 biodiesel standards.

scholarly journals Biodiesel Production over Niobium-Containing Catalysts: A Review

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5506
Author(s):  
Daniel Carreira Batalha ◽  
Márcio José da Silva
Keyword(s):  
Catalytic Activity ◽  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Raw Materials ◽  
Catalytic Performance ◽  
High Specific Surface Area ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Main Reaction ◽  
High Catalytic Activity

Nowadays, the synthesis of biofuels from renewable raw materials is very popular. Among the various challenges involved in improving these processes, environmentally benign catalysts compatible with an inexpensive feedstock have become more important. Herein, we report the recent advances achieved in the development of Niobium-containing heterogeneous catalysts as well as their use in routes to produce biodiesel. The efficiency of different Niobium catalysts in esterification and transesterification reactions of lipids and oleaginous raw materials was evaluated, considering the effect of main reaction parameters such as temperature, time, catalyst load, and oil:alcohol molar ratio on the biodiesel yield. The catalytic performance of Niobium compounds was discussed considering the characterization data obtained by different techniques, including NH3-TPD, BET, and Pyr-FT-IR analysis. The high catalytic activity is attributed to its inherent properties, such as the active sites distribution over a high specific surface area, strength of acidity, nature, amount of acidic sites, and inherent mesoporosity. On top of this, recycling experiments have proven that most Niobium catalysts are stable and can be repeatedly used with consistent catalytic activity.

scholarly journals KRITERIA RUMAH MAKAN SUPPLIER MINYAK JELANTAH DALAM RANGKA PERENCANAAN BAHAN BAKU BIODIESEL

2019 ◽  
Vol 1 (1) ◽  
pp. 27-33
Author(s):  
D.U.M. Susilo ◽  
Th. Candra Wasis A.S. ◽  
Zakwan .
Keyword(s):  
Raw Materials ◽  
Waste Cooking Oil ◽  
Raw Material ◽  
Biodiesel Production ◽  
Analytic Hierarchy ◽  
Cooking Oil ◽  
Used Cooking Oil ◽  
A Value ◽  
Many Sources ◽  
The City

The using of biodiesel as an environmentally friendly fuel has received attention from consumers to producers. So, a lot of research was done on the potential raw material to become biodiesel. One of the raw materials for biodiesel was waste cooking oil. Pontianak City have many sources including waste cooking oil from restaurants. Therefore restaurants in the city of Pontianak might be used as suppliers of waste cooking oil in biodiesel production. This study aims to determine the priority of criteria and sub-criteria for restaurants as suppliers and determine good restaurants as suppliers of used cooking in Pontianak City . Purposive technique sampling using a sample of 61 house dining, interviewed to obtain alternative data suppliers. Expert survey questionnaire contains priority weighting of criteria and supplier criteria, analyzed using AHP ( Analytic Hierarchy Process ). Grouping of restaurants based on alternative supplier values ​​is used to determine good restaurants to be suppliers. The priority criteria for restaurants as consecutive suppliers are experience (0.289), quality (0.279), capacity (0.231), service (0.148) and price (0.053). Sub-criteria priority of restaurants as suppliers in a row is the time span of used cooking oil sold(0.161), length of time used cooking oil (0.155), income (0.129), type of cooking oil (0.107), type of fried food products (0.092), volume of cooking oil (0.090), frying volume (0.085), transaction convenience (0.082), subject to used cooking oil (0.056), used cooking oil price (0.030) and ease of payment (0.013). A value of ≥ 0.325 is a dining value that shows a very better priority as a supplier. The number of restaurants as suppliers is 8 % of the population of restaurants in the city of Pontianak..

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