scholarly journals Progress of Metal Oxide (Sulfide)-Based Photocatalytic Materials for Reducing Nitrogen to Ammonia

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Jianjun Yang
Keyword(s):  
Energy Consumption ◽  
Metal Oxide ◽  
Production Process ◽  
High Energy ◽  
Research Field ◽  
Ammonia Production ◽  
Ambient Conditions ◽  
Promising Alternative ◽  
Important Approach ◽  
Photocatalytic Materials

The Haber–Bosch process has been an important approach to produce ammonia for meeting the food need of increasing population and the worldwide need of nitrogenous fertilizers since 1913. However, the traditional ammonia production process is a high energy-consumption process, which usually produces 1 metric ton ammonia with releasing around 1.9 metric tons CO2. Photocatalytic ammonia synthesis under solar light as energy source, an attractive and promising alternative approach, is a very challenging target of reducing fossil energy consumption and environmental pollution. Therefore, photocatalytic ammonia production process would emerge huge opportunities by directly providing nitrogenous fertilizers in a distributed manner as needed in the agricultural fields. In this article, different metal oxide (sulfide)-based photocatalytic materials for reducing nitrogen to ammonia under ambient conditions are reviewed. This review provides insights into the most recent advancements in understanding the photocatalyst materials which are of fundamental significance to photocatalytic nitrogen reduction, including the state-of-the-art, challenges, and prospects in this research field.

scholarly journals Progress in Synthesizing Analogues of Nitrogenase Metalloclusters for Catalytic Reduction of Nitrogen to Ammonia

Catalysts ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 939
Author(s):  
Yang
Keyword(s):  
Energy Consumption ◽  
Catalytic Reduction ◽  
High Energy ◽  
Ambient Conditions ◽  
Promising Alternative ◽  
Fossil Energy ◽  
Alternative Approach ◽  
Increasing Demand ◽  
High Energy Consumption ◽  
Significant Opportunity

Ammonia (NH3) has played an essential role in meeting the increasing demand for food and the worldwide need for nitrogen (N2) fertilizer since 1913. Unfortunately, the traditional Haber–Bosch process for producing NH3 from N2 is a high energy-consumption process with approximately 1.9 metric tons of fossil CO2 being released per metric ton of NH3 produced. As a very challenging target, any ideal NH3 production process reducing fossil energy consumption and environmental pollution would be welcomed. Catalytic NH3 synthesis is an attractive and promising alternative approach. Therefore, developing efficient catalysts for synthesizing NH3 from N2 under ambient conditions would create a significant opportunity to directly provide nitrogenous fertilizers in agricultural fields as needed in a distributed manner. In this paper, the literature on alternative, available, and sustainable NH3 production processes in terms of the scientific aspects of the spatial structures of nitrogenase metalloclusters, the mechanism of reducing N2 to NH3 catalyzed by nitrogenase, the synthetic analogues of nitrogenase metalloclusters, and the opportunities for continued research are reviewed.

scholarly journals A Study on the Application Characteristics of the Insoluble MMO (Mixed Metal Oxide) Electrode for Energy Reduction of Zinc Electrowinning Process

2020 ◽  
Vol 42 (9) ◽  
pp. 424-430
Author(s):  
Mijung Park ◽  
Taeksoon Lee
Keyword(s):  
Energy Consumption ◽  
Metal Oxide ◽  
Energy Use ◽  
Deposition Efficiency ◽  
High Energy ◽  
Alloy Electrode ◽  
Mixed Metal Oxide ◽  
Zinc Electrowinning ◽  
Oxide Electrode ◽  
Zinc Deposition

Objective : The zinc electrowinning industry is one of the high energy consumption industries where energy saving is required. In the zinc electrowining process, electrode is a high energy consuming part. In order to reduce energy use in the electrolytic smelting industry, a comparative study was conducted on the current usage of Pb+Ag alloy electrode and insoluble composite metal oxide (MMO) electrode.Methods : In this study, a comparative evaluation of energy consumption was conducted between the generally used Pb+Ag alloy electrode and an insoluble MMO electrode. Aluminum was used as a reducing electrode. The actual on-site zinc electrowinning solution and ZnSO₄ simulated solution were prepared to estimate the electrode potential, voltage, zinc deposition efficiency, and lifetime characteristics under the current density of 500 A/m².Results and Discussion : The overvoltage of the insoluble MMO electrode was 28.9% lower and the voltage was 15.0% lower than that of Pb+Ag alloy electrode. The zinc deposition efficiency of the insoluble MMO electrode was higher 1.9% in the actual on-site zinc electrowinning solution and 6.3% in the simulated solution. Compared with the Pb+Ag alloy electrode in use, the insoluble composite metal oxide electrode exhibited low overvoltage, good voltage characteristics, and high current efficiency characteristics.Conclusions : When the energy consumption of the Pb+Ag alloy and the insoluble MMO electrodes was compared, The insoluble MMO electrode showed 17.0% lower energy consumption in the actual on-site zinc electrowinning solution and 23.8% lower in the ZnSO₄ simulated solution than Pb+Ag alloy electrode.

scholarly journals Evaluation of Ionic Liquids as In Situ Extraction Agents during the Alcoholic Fermentation of Carob Pod Extracts

Fermentation ◽  
2019 ◽  
Vol 5 (4) ◽  
pp. 90 ◽  
Author(s):  
Sergio Sanchez-Segado ◽  
María José Salar-García ◽  
Víctor Manuel Ortiz-Martínez ◽  
Antonia Pérez de los Ríos ◽  
Francisco José Hernández-Fernández ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Energy Consumption ◽  
Molecular Sieves ◽  
Alcoholic Fermentation ◽  
Current System ◽  
Extractive Distillation ◽  
High Energy ◽  
Anhydrous Ethanol ◽  
Carbohydrate Source ◽  
Promising Alternative

Anhydrous ethanol is a promising alternative to gasoline in fuel engines. However, since ethanol forms an azeotrope with water, high-energy-consumption separation techniques such as azeotropic distillation, extractive distillation, and molecular sieves are needed to produce anhydrous ethanol. This work discusses the potential development of an integrated process for bioethanol production using ionic liquids and Ceratonia siliqua as a carbohydrate source for further fermentation of the aqueous extracts. A four-stage counter-current system was designed to improve the sugar extraction yield to values close to 99%. The alcoholic fermentation of the extracts showed ethanol concentrations of 95 g/L using the microorganism Saccharomyces cerevisae. The production of anhydrous ethanol through extractive distillation with ethylene glycol was simulated using CHEMCAD software, with an energy consumption of 13.23 MJ/Kg of anhydrous ethanol. Finally, several ionic liquids were analyzed and are proposed as potential solvents for the recovery of bioethanol for the design of an integrated extraction–fermentation–separation process, according to their ability to extract ethanol from aqueous solutions and their biocompatibility with the microorganism used in this study.

scholarly journals Optimal Scheduling of Campus Microgrid Considering the Electric Vehicle Integration in Smart Grid

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 7133
Author(s):  
Tehreem Nasir ◽  
Safdar Raza ◽  
Muhammad Abrar ◽  
Hafiz Abd ul Muqeet ◽  
Harun Jamil ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Power Supply ◽  
Linear Optimization ◽  
Clean Energy ◽  
High Energy ◽  
Energy Resources ◽  
Pv System ◽  
Promising Alternative ◽  
Continuous Power ◽  
The Impact

High energy consumption, rising environmental concerns and depleting fossil fuels demand an increase in clean energy production. The enhanced resiliency, efficiency and reliability offered by microgrids with distributed energy resources (DERs) have shown to be a promising alternative to the conventional grid system. Large-sized commercial customers like institutional complexes have put significant efforts to promote sustainability by establishing renewable energy systems at university campuses. This paper proposes the integration of a photovoltaic (PV) system, energy storage system (ESS) and electric vehicles (EV) at a University campus. An optimal energy management system (EMS) is proposed to optimally dispatch the energy from available energy resources. The problem is mapped in a Linear optimization problem and simulations are carried out in MATLAB. Simulation results showed that the proposed EMS ensures the continuous power supply and decreases the energy consumption cost by nearly 45%. The impact of EV as a storage tool is also observed. EVs acting as a source of energy reduced the energy cost by 45.58% and as a load by 19.33%. The impact on the cost for continuous power supply in case of a power outage is also analyzed.

Freight Energy Use Disaggregated by Commodity: Comparisons and Discussion

1998 ◽  
Vol 1641 (1) ◽  
pp. 3-8 ◽  
Author(s):  
Francis M. Vanek ◽  
Edward K. Morlok
Keyword(s):  
Energy Consumption ◽  
Energy Use ◽  
Raw Materials ◽  
High Energy ◽  
Modal Shift ◽  
Commodity Group ◽  
Conservation Policies ◽  
Average Value ◽  
Important Approach ◽  
Intensity Estimate

The analysis of energy consumption in freight transportation is almost always approached by disaggregating overall energy consumption by mode, which then provides a basis for understanding trends and underlying factors that influence them and for developing conservation policies. Another important approach is to disaggregate by commodity, because it is commodity flows that generate the modal vehicle flows and hence the modal energy consumption in transportation. Thus changes in energy use by commodity are important factors in understanding trends in energy consumption and may provide a basis for energy conservation policies centered on industries using transportation. Total freight energy consumption is estimated for a range of commodity groups using an activitybased approach to energy consumption, where total freight activity is decomposed into components by mode and by commodity group, and then each component is multiplied by an intensity estimate to calculate total energy use for that commodity group. Two important findings are discussed: ( a) commodity groups with high energy growth between 1972 and 1993 had a combination of substantial ton-mile growth and modal shift to truck, and ( b) commodity groups of finished products with a high average value per ton in general have a much higher average freight energy intensity than raw materials with a low average value per ton.

Separation of Biologically Active Compounds by Membrane Operations

2017 ◽  
Vol 23 (2) ◽  
pp. 218-230 ◽  
Author(s):  
Xiaoying Zhu ◽  
Renbi Bai
Keyword(s):  
Energy Consumption ◽  
Bioactive Compounds ◽  
Membrane Fouling ◽  
Membrane Separation ◽  
Separation Efficiency ◽  
High Energy ◽  
Separation Processes ◽  
Membrane Processes ◽  
Separation Technology ◽  
Pressure Driven

Background: Bioactive compounds from various natural sources have been attracting more and more attention, owing to their broad diversity of functionalities and availabilities. However, many of the bioactive compounds often exist at an extremely low concentration in a mixture so that massive harvesting is needed to obtain sufficient amounts for their practical usage. Thus, effective fractionation or separation technologies are essential for the screening and production of the bioactive compound products. The applicatons of conventional processes such as extraction, distillation and lyophilisation, etc. may be tedious, have high energy consumption or cause denature or degradation of the bioactive compounds. Membrane separation processes operate at ambient temperature, without the need for heating and therefore with less energy consumption. The “cold” separation technology also prevents the possible degradation of the bioactive compounds. The separation process is mainly physical and both fractions (permeate and retentate) of the membrane processes may be recovered. Thus, using membrane separation technology is a promising approach to concentrate and separate bioactive compounds. Methods: A comprehensive survey of membrane operations used for the separation of bioactive compounds is conducted. The available and established membrane separation processes are introduced and reviewed. Results: The most frequently used membrane processes are the pressure driven ones, including microfiltration (MF), ultrafiltration (UF) and nanofiltration (NF). They are applied either individually as a single sieve or in combination as an integrated membrane array to meet the different requirements in the separation of bioactive compounds. Other new membrane processes with multiple functions have also been developed and employed for the separation or fractionation of bioactive compounds. The hybrid electrodialysis (ED)-UF membrane process, for example has been used to provide a solution for the separation of biomolecules with similar molecular weights but different surface electrical properties. In contrast, the affinity membrane technology is shown to have the advantages of increasing the separation efficiency at low operational pressures through selectively adsorbing bioactive compounds during the filtration process. Conclusion: Individual membranes or membrane arrays are effectively used to separate bioactive compounds or achieve multiple fractionation of them with different molecule weights or sizes. Pressure driven membrane processes are highly efficient and widely used. Membrane fouling, especially irreversible organic and biological fouling, is the inevitable problem. Multifunctional membranes and affinity membranes provide the possibility of effectively separating bioactive compounds that are similar in sizes but different in other physical and chemical properties. Surface modification methods are of great potential to increase membrane separation efficiency as well as reduce the problem of membrane fouling. Developing membranes and optimizing the operational parameters specifically for the applications of separation of various bioactive compounds should be taken as an important part of ongoing or future membrane research in this field.

scholarly journals Current Knowledge and Future Directions for Improving Subsoiling Quality and Reducing Energy Consumption in Conservation Fields

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 575
Author(s):  
Shangyi Lou ◽  
Jin He ◽  
Hongwen Li ◽  
Qingjie Wang ◽  
Caiyun Lu ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Cover Crops ◽  
Current Knowledge ◽  
High Energy ◽  
Field Application ◽  
Research Progress ◽  
Monitoring And Control ◽  
Future Directions ◽  
Tillage Depth ◽  
And Control

Subsoiling has been acknowledged worldwide to break compacted hardpan, improve soil permeability and water storage capacity, and promote topsoil deepening and root growth. However, there exist certain factors which limit the wide in-field application of subsoiling machines. Of these factors, the main two are poor subsoiling quality and high energy consumption, especially the undesired tillage depth obtained in the field with cover crops. Based on the analysis of global adoption and benefits of subsoiling technology, and application status of subsoiling machines, this article reviewed the research methods, technical characteristics, and developing trends in five key aspects, including subsoiling shovel design, anti-drag technologies, technologies of tillage depth detection and control, and research on soil mechanical interaction. Combined with the research progress and application requirements of subsoiling machines across the globe, current problems and technical difficulties were analyzed and summarized. Aiming to solve these problems, improve subsoiling quality, and reduce energy consumption, this article proposed future directions for the development of subsoiling machines, including optimizing the soil model in computer simulation, strengthening research on the subsoiling mechanism and comprehensive effect, developing new tillage depth monitoring and control systems, and improving wear-resisting properties of subsoiling shovels.

scholarly journals Nanoscale optical writing through upconversion resonance energy transfer

2021 ◽  
Vol 7 (9) ◽  
pp. eabe2209
Author(s):  
S. Lamon ◽  
Y. Wu ◽  
Q. Zhang ◽  
X. Liu ◽  
M. Gu
Keyword(s):  
Graphene Oxide ◽  
Energy Transfer ◽  
Energy Consumption ◽  
Data Storage ◽  
High Capacity ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
High Energy ◽  
Optical Data ◽  
Upconversion Nanoparticles

Nanoscale optical writing using far-field super-resolution methods provides an unprecedented approach for high-capacity data storage. However, current nanoscale optical writing methods typically rely on photoinitiation and photoinhibition with high beam intensity, high energy consumption, and short device life span. We demonstrate a simple and broadly applicable method based on resonance energy transfer from lanthanide-doped upconversion nanoparticles to graphene oxide for nanoscale optical writing. The transfer of high-energy quanta from upconversion nanoparticles induces a localized chemical reduction in graphene oxide flakes for optical writing, with a lateral feature size of ~50 nm (1/20th of the wavelength) under an inhibition intensity of 11.25 MW cm−2. Upconversion resonance energy transfer may enable next-generation optical data storage with high capacity and low energy consumption, while offering a powerful tool for energy-efficient nanofabrication of flexible electronic devices.

scholarly journals Mitigating the Energy Consumption and the Carbon Emission in the Building Structures by Optimization of the Construction Processes

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3287
Author(s):  
Alireza Tabrizikahou ◽  
Piotr Nowotarski
Keyword(s):  
Life Cycle ◽  
Energy Consumption ◽  
Structural Optimization ◽  
Carbon Emissions ◽  
Carbon Emission ◽  
Construction Materials ◽  
High Energy ◽  
Building Structures ◽  
Life Cycle Stages ◽  
Reduction Of Energy Consumption

For decades, among other industries, the construction sector has accounted for high energy consumption and emissions. As the energy crisis and climate change have become a growing concern, mitigating energy usage is a significant issue. The operational and end of life phases are all included in the building life cycle stages. Although the operation stage accounts for more energy consumption with higher carbon emissions, the embodied stage occurs in a time-intensive manner. In this paper, an attempt has been made to review the existing methods, aiming to lower the consumption of energy and carbon emission in the construction buildings through optimizing the construction processes, especially with the lean construction approach. First, the energy consumption and emissions for primary construction materials and processes are introduced. It is followed by a review of the structural optimization and lean techniques that seek to improve the construction processes. Then, the influence of these methods on the reduction of energy consumption is discussed. Based on these methods, a general algorithm is proposed with the purpose of improving the construction processes’ performance. It includes structural optimization and lean and life cycle assessments, which are expected to influence the possible reduction of energy consumption and carbon emissions during the execution of construction works.

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