Studies of TiO2 Ceramics Structure after Thermal Treatment at Different Conditions

The present work describes results of investigation of structural characteristics of TiO2 ceramics, depending on temperature and thermal treatment conditions by using a variety of characterization techniques. TiO2 ceramics was prepared by extrusion method and developed as a material for electrodes for innovative water treatment technologies. It was shown that non-stoichiometric phase TiO1.95 was observed after thermal treatment of TiO2 ceramics under high vacuum conditions.

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The influence of thermal treatment conditions on the properties of TiO2 ceramics

World Journal of Engineering ◽

10.1260/1708-5284.11.2.131 ◽

2014 ◽

Vol 11 (2) ◽

pp. 131-138

Author(s):

Inga Narkevica ◽

Jurijs Ozolins ◽

Kristaps Rubenis ◽

Janis Kleperis ◽

Janis Locs ◽

...

Keyword(s):

Electrical Conductivity ◽

Thermal Treatment ◽

High Vacuum ◽

Extrusion Process ◽

Oxide Ceramics ◽

Mechanical And Electrical Properties ◽

Treatment Conditions ◽

Extrusion Technology ◽

Nonstoichiometric Titanium ◽

Resistant Ceramic

The influence of thermal treatment conditions on titanium dioxide ceramics phase transformation, microstructure, physico-mechanical and electrical properties was studied. TiO2 ceramic was prepared using extrusion technology and thermal treatment in air and subsequent annealing under high vacuum conditions. It has been observed that intense TiO2 ceramic mass sintering occurs over the temperature ranging from 950 °C to 1100 °C. It is accompanied by crystallographic modification change from anatase to rutile. Ceramic sample annealing in vacuum causes formation of nonstoichiometric titanium oxide ceramics and as a result electrical conductivity of the material significantly increases. Using extrusion process relatively dense and mechanically resistant ceramic material can be obtained that can be used in different technological processes.

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Effect of thermal treatment conditions on the phase composition and structural characteristics of V-Mo-Nb-O catalysts

Kinetics and Catalysis ◽

10.1134/s0023158409010078 ◽

2009 ◽

Vol 50 (1) ◽

pp. 48-56 ◽

Cited By ~ 4

Author(s):

T. Yu. Kardash ◽

L. M. Plyasova ◽

V. M. Bondareva ◽

T. V. Andrushkevich ◽

A. V. Ishchenko ◽

...

Keyword(s):

Phase Composition ◽

Thermal Treatment ◽

Structural Characteristics ◽

Treatment Conditions

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Electrochemical Studies of Nonstoichiometric TiO2-x Ceramic

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.604.254 ◽

2014 ◽

Vol 604 ◽

pp. 254-257

Author(s):

Inga Narkevica ◽

Madars Reimanis ◽

Janis Kleperis ◽

Jurijs Ozolins ◽

Liga Berzina-Cimdina

Keyword(s):

Electrical Conductivity ◽

Water Treatment ◽

Thermal Treatment ◽

Titanium Oxide ◽

High Vacuum ◽

Oxide Ceramic ◽

Electrochemical Studies ◽

Two Stages ◽

Extrusion Technology ◽

Nonstoichiometric Titanium

TiO2 ceramic was prepared using extrusion technology and thermal treatment in two stages: sintering in air and subsequent annealing under high vacuum conditions. Sample thermal treatment in high vacuum conditions causes formation of nonstoichiometric titanium oxide ceramic. As a result electrical conductivity of the material significantly increases. Such a material can be used for electrode production for electrochemical water treatment.

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PRACTICAL APPLICATIONS AND EVOLUTION OF THE NEW WATER TREATMENT TECHNOLOGIES

Environmental Engineering and Management Journal ◽

10.30638/eemj.2007.045 ◽

2007 ◽

Vol 6 (5) ◽

pp. 375-379

Author(s):

Ilie Vlaicu

Keyword(s):

Water Treatment ◽

Practical Applications ◽

Treatment Technologies

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Methods, Protocols, Guidance and Standards for Performance Evaluation for Point-of-Use Water Treatment Technologies: History, Current Status, Future Needs and Directions

Water ◽

10.3390/w13081094 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1094

Author(s):

Emily S. Bailey ◽

Nikki Beetsch ◽

Douglas A. Wait ◽

Hemali H. Oza ◽

Nirmala Ronnie ◽

...

Keyword(s):

Drinking Water ◽

Water Treatment ◽

Enteric Bacteria ◽

Current Status ◽

Household Water Treatment ◽

Produce Water ◽

Point Of Use ◽

Treatment Technologies ◽

Injury And Repair ◽

Testing Protocols

It is estimated that 780 million people do not have access to improved drinking water sources and approximately 2 billion people use fecally contaminated drinking water. Effective point-of-use water treatment systems (POU) can provide water with sufficiently reduced concentrations of pathogenic enteric microorganisms to not pose significant health risks to consumers. Household water treatment (HWT) systems utilize various technologies that physically remove and/or inactivate pathogens. A limited number of governmental and other institutional entities have developed testing protocols to evaluate the performance of POU water treatment systems. Such testing protocols are essential to documenting effective performance because inferior and ineffective POU treatment technologies are thought to be in widespread use. This critical review examines specific practices, procedures and specification of widely available POU system evaluation protocols. Testing protocols should provide standardized and detailed instructions yet be sufficiently flexible to deal with different treatment technologies, test microbe priorities and choices, testing facility capabilities and public health needs. Appropriate infectivity or culture assays should be used to quantify test enteric bacteria, viruses and protozoan parasites, or other appropriate surrogates or substitutes for them, although processes based on physical removal can be tested by methods that detect microbes as particles. Recommendations include further research of stock microbe production and handling methods to consistently yield test microbes in a realistic state of aggregation and, in the case of bacteria, appropriately physiologically stressed. Bacterial quantification methods should address the phenomenon of bacterial injury and repair in order to maximally recover those that are culturable and potentially infectious. It is only with harmonized national and international testing protocols and performance targets that independent and unbiased testing can be done to assure consumers that POU treatment technologies are able to produce water of high microbial quality and low health risk.

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Long-lasting, monovalent-selective capacitive deionization electrodes

npj Clean Water ◽

10.1038/s41545-021-00109-2 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Eric N. Guyes ◽

Amit N. Shocron ◽

Yinke Chen ◽

Charles E. Diesendruck ◽

Matthew E. Suss

Keyword(s):

Water Treatment ◽

Ionic Conductivity ◽

Ion Selectivity ◽

Single Step ◽

Carbon Electrodes ◽

Capacitive Deionization ◽

Treatment Technologies ◽

Porous Carbon Electrodes ◽

Monovalent Ion ◽

Direct Use

AbstractEmerging water purification applications often require tunable and ion-selective technologies. For example, when treating water for direct use in irrigation, often monovalent Na+ must be removed preferentially over divalent minerals, such as Ca2+, to reduce both ionic conductivity and sodium adsorption ratio (SAR). Conventional membrane-based water treatment technologies are either largely non-selective or not dynamically tunable. Capacitive deionization (CDI) is an emerging membraneless technology that employs inexpensive and widely available activated carbon electrodes as the active element. We here show that a CDI cell leveraging sulfonated cathodes can deliver long-lasting, tunable monovalent ion selectivity. For feedwaters containing Na+ and Ca2+, our cell achieves a Na+/Ca2+ separation factor of up to 1.6. To demonstrate the cell longevity, we show that monovalent selectivity is retained over 1000 charge–discharge cycles, the highest cycle life achieved for a membraneless CDI cell with porous carbon electrodes to our knowledge, while requiring an energy consumption of ~0.38 kWh/m3 of treated water. Furthermore, we show substantial and simultaneous reductions of ionic conductivity and SAR, such as from 1.75 to 0.69 mS/cm and 19.8 to 13.3, respectively, demonstrating the potential of such a system towards single-step water treatment of brackish and wastewaters for direct use in irrigation.

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