scholarly journals Comparison of Material Activity and Selectivity in the Electrocatalytic Oxidation of Dibenzothiophene

2021 ◽  
Author(s):  
John Swierk ◽  
Victoria Kompanijec
Keyword(s):  
Water Oxidation ◽  
Oxidative Desulfurization ◽  
Cost Effective ◽  
Oxidation Products ◽  
Faradaic Efficiency ◽  
Cost Effective Method ◽  
Fuel Oils ◽  
Increasing Demand ◽  
Sulfur Containing ◽  
Electrochemical Catalysts

Due to adverse effects of sulfur-containing compounds present in fuel oils, there is an increasing demand for an efficient and cost-effective method of removing sulfur from oil products, such as oxidative desulfurization. In this work, a set of five materials (gold, glassy carbon, nickel, palladium and platinum) were evaluated as electrochemical catalysts for the oxidation of DBT. Electrolysis at 1.58 V was performed without water present (producing a dimer of DBT) and with the addition of 2 M water (producing DBTO). LC-MS and NMR were used to characterize the oxidation products. It was found that the Faradaic efficiencies ranged from 18.4 – 56.5% for consumption of DBT without water present and there was a correlation between higher rate constants, lower activation energies and more efficient DBT oxidation. After the addition of water, the formation of DBTO was found to have the highest selectivity when catalyzed by gold, with a Faradaic efficiency of 87.9%. The group ten metals demonstrated low Faradaic efficiencies due to the competitive water oxidation taking place. Though there were differences in the observed selectivity for DBT oxidation, all catalysts reduced the concentration of DBT in solution by similar amounts. Of the materials tested, gold served as the most selective for oxidation to DBTO, with the presence of water improving the overall reaction activity.

scholarly journals Comparison of Material Activity and Selectivity in the Electrocatalytic Oxidation of Dibenzothiophene

2021 ◽  
Author(s):  
Victoria Kompanjiec ◽  
John R Swierk
Keyword(s):  
Water Oxidation ◽  
Electrocatalytic Oxidation ◽  
Oxidative Desulfurization ◽  
Oxidation Products ◽  
Faradaic Efficiency ◽  
Lower Activation ◽  
Bulk Electrolysis ◽  
Percent Conversion ◽  
Increasing Demand ◽  
Electrochemical Catalysts

Abstract There is an increasing demand for efficient methods to remove sulfur from oil products, such as oxidative desulfurization. In this work, a set of five materials (gold, glassy carbon, nickel, palladium and platinum) were evaluated as electrochemical catalysts for the oxidation of dibenzothiophene (DBT). Bulk electrolysis performed without water present, produced DBT dimer, while the addition of 2 M water, produced dibenzothiophene sulfoxide (DBTO), both more polar than DBT. LC-MS and NMR were used to characterize the oxidation products. Faradaic efficiencies ranged from 18.4–56.5% for DBT consumption without water present, and there was a correlation between higher rate constants, lower activation energies and more efficient DBT oxidation. With water present, selectivity for DBTO formation was highest using gold, with a Faradaic efficiency of 87.9%. Group ten metals demonstrated low Faradaic efficiencies due to competitive water oxidation. Though there were differences in the observed selectivity for DBT oxidation, all catalysts reduced the concentration of DBT in solution by similar amounts. Our findings indicate that the overall percent conversion does not give a complete picture of catalytic activity. Of the materials tested, gold was the most selective for oxidation to DBTO, with the presence of water improving the overall reaction activity.

Statistical Optimization of the Production of alpha-Amylase from Bacillus licheniformis MTCC 1483 Using Paddy Straw as Substrate

2017 ◽  
Vol 23 (2) ◽  
Author(s):  
Palki Sahib Kaur ◽  
Sukhjeet Kaur ◽  
Hardish Kaur ◽  
Sonica Sondhi
Keyword(s):  
Solid State ◽  
Bacillus Licheniformis ◽  
Solid State Fermentation ◽  
Enzyme Production ◽  
Cost Effective ◽  
Fold Increase ◽  
Paddy Straw ◽  
Cost Effective Method ◽  
Increasing Demand ◽  
Optimized Conditions

?-Amylase has been in increasing demand in industries due to its hydrolytic nature. Solid state fermentation (SSF) is a cost effective method for increasing the enzyme production. In the present study, amylase from Bacillus licheniformis MTCC 1483 was produced in large quantity by solid state fermentation using paddy straw as substrate. Response surface methodology is a useful tool for optimizing many parameters at a time and is used for increasing the amylase production. 8523 IUg-1 of enzyme activity was obtained under optimized conditions which lead to 35 fold increase in the yield of amylase from unoptimized condition.

CAD Of Anticorrosive Protection Of Steel Structures

2019 ◽  
pp. 18-23
Keyword(s):  
Protective Coating ◽  
Computer Aided Design ◽  
Steel Structures ◽  
Cost Effective ◽  
Operating Conditions ◽  
Computational Tool ◽  
Protection Method ◽  
Cost Effective Method ◽  
The Cost ◽  
Aided Design

The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.

Monitoring effluent quality in hypertrophic wastewater reservoirs using remote sensing

1996 ◽  
Vol 33 (8) ◽  
pp. 23-29 ◽  
Author(s):  
I. Dor ◽  
N. Ben-Yosef
Keyword(s):  
Water Quality ◽  
Theoretical Model ◽  
Principal Component ◽  
Cost Effective ◽  
Operational Parameters ◽  
Effluent Quality ◽  
Optical Images ◽  
Routine Monitoring ◽  
Cost Effective Method ◽  
Wastewater Quality

About one hundred and fifty wastewater reservoirs store effluents for irrigation in Israel. Effluent qualities differ according to the inflowing wastewater quality, the degree of pretreatment and the operational parameters. Certain aspects of water quality like concentration of organic matter, suspended solids and chlorophyll are significantly correlated with the water column transparency and colour. Accordingly optical images of the reservoirs obtained from the SPOT satellite demonstrate pronounced differences correlated with the water quality. The analysis of satellite multispectral images is based on a theoretical model. The model calculates, using the radiation transfer equation, the volume reflectance of the water body. Satellite images of 99 reservoirs were analyzed in the chromacity space in order to classify them according to water quality. Principal Component Analysis backed by the theoretical model increases the method sensitivity. Further elaboration of this approach will lead to the establishment of a time and cost effective method for the routine monitoring of these hypertrophic wastewater reservoirs.

A Cost-Effective Method to Prepare Pure Vildagliptin

2013 ◽  
Vol 10 (3) ◽  
pp. 159-163 ◽  
Author(s):  
Jun Peng ◽  
Yue Feng ◽  
Zhu Tao ◽  
Yingjie Chen ◽  
Xiangnan Hu
Keyword(s):  
Cost Effective ◽  
Cost Effective Method

scholarly journals Computer-supported Detection of M-Components and Evaluation of Immunoglobulins after Capillary Electrophoresis

2001 ◽  
Vol 47 (1) ◽  
pp. 110-117 ◽  
Author(s):  
Magnus Jonsson ◽  
Joyce Carlson ◽  
Jan-Olof Jeppsson ◽  
Per Simonsson
Keyword(s):  
Capillary Electrophoresis ◽  
Decision Support ◽  
Protein Separation ◽  
Serum Proteins ◽  
Cost Effective ◽  
Clinical Samples ◽  
Serum Samples ◽  
Computerized Decision Support ◽  
Cost Effective Method ◽  
Mathematical Algorithms

Abstract Background: Electrophoresis of serum samples allows detection of monoclonal gammopathies indicative of multiple myeloma, Waldenström macroglobulinemia, monoclonal gammopathy of undetermined significance, and amyloidosis. Present methods of high-resolution agarose gel electrophoresis (HRAGE) and immunofixation electrophoresis (IFE) are manual and labor-intensive. Capillary zone electrophoresis (CZE) allows rapid automated protein separation and produces digital absorbance data, appropriate as input for a computerized decision support system. Methods: Using the Beckman Paragon CZE 2000 instrument, we analyzed 711 routine clinical samples, including 95 monoclonal components (MCs) and 9 cases of Bence Jones myeloma, in both the CZE and HRAGE systems. Mathematical algorithms developed for the detection of monoclonal immunoglobulins (MCs) in the γ- and β-regions of the electropherogram were tested on the entire material. Additional algorithms evaluating oligoclonality and polyclonal concentrations of immunoglobulins were also tested. Results: CZE electropherograms corresponded well with HRAGE. Only one IgG MC of 1 g/L, visible on HRAGE, was not visible after CZE. Algorithms detected 94 of 95 MCs (98.9%) and 100% of those visible after CZE. Of 607 samples lacking an MC on HRAGE, only 3 were identified by the algorithms (specificity, 99%). Algorithms evaluating total gammaglobulinemia and oligoclonality also identified several cases of Bence Jones myeloma. Conclusions: The use of capillary electrophoresis provides a modern, rapid, and cost-effective method of analyzing serum proteins. The additional option of computerized decision support, which provides rapid and standardized interpretations, should increase the clinical availability and usefulness of protein analyses in the future.

scholarly journals CO$$_{2}$$ Convection in Hydrocarbon Under Flowing Conditions

2021 ◽  
Author(s):  
Trine S. Mykkeltvedt ◽  
Sarah E. Gasda ◽  
Tor Harald Sandve
Keyword(s):  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Flow Behavior ◽  
Cost Effective ◽  
Fine Grid ◽  
Cost Effective Method ◽  
Gravity Effects ◽  
Petroleum Resources ◽  
Nearby Point ◽  
Diffusive Processes

AbstractCarbon-neutral oil production is one way to improve the sustainability of petroleum resources. The emissions from produced hydrocarbons can be offset by injecting capture CO$$_{2}$$ 2 from a nearby point source into a saline aquifer for storage or a producing oil reservoir. The latter is referred to as enhanced oil recovery (EOR) and would enhance the economic viability of CO$$_{2}$$ 2 sequestration. The injected CO$$_{2}$$ 2 will interact with the oil and cause it to flow more freely within the reservoir. Consequently, the overall recovery of oil from the reservoir will increase. This enhanced oil recovery (EOR) technique is perceived as the most cost-effective method for disposing captured CO$$_{2}$$ 2 emissions and has been performed for many decades with the focus on oil recovery. The interaction between existing oil and injected CO$$_{2}$$ 2 needs to be fully understood to effectively manage CO$$_{2}$$ 2 migration and storage efficiency. When CO$$_{2}$$ 2 and oil mix in a fully miscible setting, the density can change non-linearly and cause density instabilities. These instabilities involve complex convective-diffusive processes, which are hard to model and simulate. The interactions occur at the sub-centimeter scale, and it is important to understand its implications for the field scale migration of CO$$_{2}$$ 2 and oil. In this work, we simulate gravity effects, namely gravity override and convective mixing, during miscible displacement of CO$$_{2}$$ 2 and oil. The flow behavior due to the competition between viscous and gravity effects is complex, and can only be accurately simulated with a very fine grid. We demonstrate that convection occurs rapidly, and has a strong effect on breakthrough of CO$$_{2}$$ 2 at the outlet. This work for the first time quantifies these effects for a simple system under realistic conditions.

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