99/01132 Low cost adsorbents for low-temperature cleaning of flue gases

Whenever possible, neutralization of alkaline wastewater should involve low-cost acid. It is conventional to make use of carbonic acid produced via the reaction of carbon dioxide (contained in flue gases) with water according to the following equation: Carbon dioxide content in the flue gas stream varies from 10% to 15%. The flue gas stream may either be passed to the wastewater contained in the recarbonizers, or. enter the scrubbers (which are continually sprayed with wastewater) from the bottom in oountercurrent. The reactors, in which recarbonation occurs, have the ability to expand the contact surface between gaseous and liquid phase. This can be achieved by gas phase dispersion in the liquid phase (bubbling), by liquid phase dispersion in the gas phase (spraying), or by bubbling and spraying, and mixing. These concurrent operations are carried out during motion of the disk aerator (which is a patent claim). The authors describe the functioning of the disk aerator, the composition of the wastewater produced during wet gasification of carbide, the chemistry of recarbonation and decarbonation, and the concept of applying the disk aerator so as to make the wastewater fit for reuse (after suitable neutralization) as feeding water in acetylene generators.

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Low-Cost Organic Adsorbents for Elemental Mercury Removal from Lignite Flue Gas

Energies ◽

10.3390/en14082174 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2174

Author(s):

Marta Marczak-Grzesik ◽

Stanisław Budzyń ◽

Barbara Tora ◽

Szymon Szufa ◽

Krzysztof Kogut ◽

...

Keyword(s):

Flue Gas ◽

Low Cost ◽

Elemental Mercury ◽

Mercury Content ◽

Flue Gases ◽

Mercury Removal ◽

Gas Purification ◽

Gas Temperature ◽

Corn Straw ◽

Flue Gas Purification

The research presented by the authors in this paper focused on understanding the behavior of mercury during coal combustion and flue gas purification operations. The goal was to determine the flue gas temperature on the mercury emissions limits for the combustion of lignites in the energy sector. The authors examined the process of sorption of mercury from flue gases using fine-grained organic materials. The main objectives of this study were to recommend a low-cost organic adsorbent such as coke dust (CD), corn straw char (CS-400), brominated corn straw char (CS-400-Br), rubber char (RC-600) or granulated rubber char (GRC-600) to efficiently substitute expensive dust-sized activated carbon. The study covered combustion of lignite from a Polish field. The experiment was conducted at temperatures reflecting conditions inside a flue gas purification installation. One of the tested sorbents—tire-derived rubber char that was obtained by pyrolysis—exhibited good potential for Hg0 into Hg2+ oxidation, resulting in enhanced mercury removal from the flue. The char characterization increased elevated bromine content (mercury oxidizing agent) in comparison to the other selected adsorbents. This paper presents the results of laboratory tests of mercury sorption from the flue gases at temperatures of 95, 125, 155 and 185 °C. The average mercury content in Polish lignite was 465 μg·kg−1. The concentration of mercury in flue gases emitted into the atmosphere was 17.8 µg·m−3. The study analyzed five low-cost sorbents with the average achieved efficiency of mercury removal from 18.3% to 96.1% for lignite combustion depending on the flue gas temperature.

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Bimetallic Ni-Based Catalysts for CO2 Methanation: A Review

Nanomaterials ◽

10.3390/nano11010028 ◽

2020 ◽

Vol 11 (1) ◽

pp. 28

Author(s):

Anastasios I. Tsiotsias ◽

Nikolaos D. Charisiou ◽

Ioannis V. Yentekakis ◽

Maria A. Goula

Keyword(s):

Low Temperature ◽

Noble Metals ◽

Recent Progress ◽

Low Cost ◽

Alloy Formation ◽

Co2 Methanation ◽

High Performing ◽

Mobile Sources ◽

Low Dispersion ◽

Made In

CO2 methanation has recently emerged as a process that targets the reduction in anthropogenic CO2 emissions, via the conversion of CO2 captured from point and mobile sources, as well as H2 produced from renewables into CH4. Ni, among the early transition metals, as well as Ru and Rh, among the noble metals, have been known to be among the most active methanation catalysts, with Ni being favoured due to its low cost and high natural abundance. However, insufficient low-temperature activity, low dispersion and reducibility, as well as nanoparticle sintering are some of the main drawbacks when using Ni-based catalysts. Such problems can be partly overcome via the introduction of a second transition metal (e.g., Fe, Co) or a noble metal (e.g., Ru, Rh, Pt, Pd and Re) in Ni-based catalysts. Through Ni-M alloy formation, or the intricate synergy between two adjacent metallic phases, new high-performing and low-cost methanation catalysts can be obtained. This review summarizes and critically discusses recent progress made in the field of bimetallic Ni-M (M = Fe, Co, Cu, Ru, Rh, Pt, Pd, Re)-based catalyst development for the CO2 methanation reaction.

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Low-temperature-processed metal oxide electron transport layers for efficient planar perovskite solar cells

Rare Metals ◽

10.1007/s12598-020-01676-y ◽

2021 ◽

Author(s):

Jia-Xing Song ◽

Xin-Xing Yin ◽

Zai-Fang Li ◽

Yao-Wen Li

Keyword(s):

Solar Cells ◽

Electron Transport ◽

Low Temperature ◽

Metal Oxide ◽

Low Cost ◽

Perovskite Solar Cells ◽

Transport Layer ◽

Electron Transport Layer ◽

Future Research ◽

Low Temperature Preparation

Abstract As a promising photovoltaic technology, perovskite solar cells (pero-SCs) have developed rapidly over the past few years and the highest power conversion efficiency is beyond 25%. Nowadays, the planar structure is universally popular in pero-SCs due to the simple processing technology and low-temperature preparation. Electron transport layer (ETL) is verified to play a vital role in the device performance of planar pero-SCs. Particularly, the metal oxide (MO) ETL with low-cost, superb versatility, and excellent optoelectronic properties has been widely studied. This review mainly focuses on recent developments in the use of low-temperature-processed MO ETLs for planar pero-SCs. The optical and electronic properties of widely used MO materials of TiO2, ZnO, and SnO2, as well as the optimizations of these MO ETLs are briefly introduced. The commonly used methods for depositing MO ETLs are also discussed. Then, the applications of different MO ETLs on pero-SCs are reviewed. Finally, the challenge and future research of MO-based ETLs toward practical application of efficient planar pero-SCs are proposed. Graphical abstract

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Large-area and low-cost Cu–Cu bonding with cold spray deposition, oxidation, and reduction processes under low-temperature conditions

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-021-06556-4 ◽

2021 ◽

Author(s):

Juncai Hou ◽

Qiumei Zhang ◽

Siliang He ◽

Jingru Bian ◽

Jinting Jiu ◽

...

Keyword(s):

Low Temperature ◽

Cold Spray ◽

Spray Deposition ◽

Low Cost ◽

Large Area ◽

Reduction Processes ◽

Temperature Conditions ◽

Cu Bonding

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Molecular Engineering for High-Performance Fullerene Broadband Photodetector

Nanoscale Advances ◽

10.1039/d0na00981d ◽

2021 ◽

Author(s):

Mingming Su ◽

Yajing Hu ◽

Ao Yu ◽

Zhiyao Peng ◽

Wangtao Long ◽

...

Keyword(s):

Electron Transfer ◽

Low Temperature ◽

Electron Acceptor ◽

Photoinduced Electron Transfer ◽

High Performance ◽

Organic Molecules ◽

Low Cost ◽

Molecular Engineering ◽

Temperature Requirement ◽

High Flexibility

Broadband photodetectors fabricated with organic molecules have the advantages of low cost, high flexibility, easy processing and low-temperature requirement. Fullerene molecules, due to the electron acceptor and photoinduced electron transfer...

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Low-temperature combustion of methane over graphene templated Co3O4 defective-nanoplates

Scientific Reports ◽

10.1038/s41598-021-92165-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Dian Gong ◽

Gaofeng Zeng

Keyword(s):

Low Temperature ◽

Transition Metal Oxides ◽

Active Oxygen Species ◽

Low Cost ◽

Thermal Reduction ◽

Low Temperature Combustion ◽

Solid Catalysts ◽

Intermittent Feeding ◽

Co Precipitation ◽

Catalytic Combustion Of Methane

AbstractTransition metal oxides are the potential catalysts to replace noble-metal based catalyst for the catalytic combustion of methane due to the tolerable reactivity and low cost. However, these catalysts are challenged by the low temperature reactivity. Herein, the surface defective Co3O4 nanoplates are realized through a facile co-precipitation and thermal reduction method with the association of GO. The resultant catalysts (CoGO50) demonstrate a superior low-temperature reactivity for the methane oxidation to CO2 and H2O in comparison with the common Co3O4 catalyst. The reliable stability of CoGO50 catalyst was proved by 80 h testing with intermittent feeding of water vapor. The experimental analysis demonstrates that the presence of a small amount of GO significantly affects the catalysts in surface valence state, active oxygen species and surface oxygen vacancies through reacting with the cobalt oxide as a reductant. Moreover, GO plays as 2D confine template to form smaller and thinner nanoplates. This work provides a facile method to control the surface properties of catalyst not only for Co3O4 based catalysts but also for wider solid catalysts.

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