• Applied Chemistry for Engineering
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• v.17 no.3
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• pp.250-254
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• 2006

Reaction of $CO_2$ with $Li_{2}ZrO_{3}$ has been investigated in a TGA and the effects of $H_{2}$ and CO on the removal of $CO_{2}$ using $Li_{2}ZrO_{3}$ were evaluated in a packed bed reactor. The initial rate of $CO_{2}$ removal reaction of $Li_{2}ZrO_{3}$ increased with the increase of gas flow rate up to 100 mL/min and then was maintained, which implied the disappearance of the gas film resistance. The reaction of $CO_{2}$ with $Li_{2}ZrO_{3}$ took place as the first order and the range of optimum temperature was found to be about $500{\sim}600^{\circ}C$. XRD and SEM analysis showed the formation of crystalline $Li_{2}ZrO_{3}$ and porous $Li_{2}ZrO_{3}$/$ZrO_{2}$. The presence of $H_{2}$ did not affect the adsorption of $CO_2$ with $Li_2ZrO_3$. On the other hand, CO inhibited the sorption of $CO_{2}$ into $Li_{2}CO_{3}$(L) on $Li_{2}ZrO_{3}$.

• Journal of the Korean Ceramic Society
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• v.44 no.1 s.296
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• pp.58-64
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• 2007

In this study, we investigated $Li_2ZrO_3$ membrane as a candidate material for high-temperature $CO_2$ separation and evaluated mechanical property. $Li_2ZrO_3$ powder was synthesized by solid state reaction of $Li_2CO_3\;and\;ZrO_2$. Then we fabricated $Li_2ZrO_3$ tape using tape casting method. Dense $Li_2ZrO_3$ membrane prepared by sintering at $1600^{\circ}C$ for 2 h after pressing $Li_2ZrO_3$ tape using lamination machine. Mechanical properties before and after $CO_2$ absorption of fabricated $Li_2ZrO_3$ membrane such as Hertzian indentation, Victors hardness and 3-point bending testing were evaluated.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.4
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• pp.229-236
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• 2012

A molten salt technology using $Li_2O$-LiCl has been extensively investigated to recover uranium metal from spent fuels in the field of nuclear energy. In the reduction process, it is an important point to maintain the concentration of $Li_2O$. $ZrO_2$ is inevitably contained in the spent fuels because Zr is one of the main components of fuel rod hulls. Therefore, the fate of $ZrO_2$ in $Li_2O$-LiCl molten salt has been investigated. It was found that $Li_2ZrO_3$ and $Li_4ZrO_4$ were formed chemically and electrochemically and they were not reduced to Zr. The recycling of $Li_2O$ is the key mechanism ruling the total reaction in the electrolytic reduction process. However, $ZrO_2$ will have a role as a $Li_2O$ sink.

• Korean Journal of Materials Research
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• v.9 no.9
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• pp.896-899
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• 1999

A carbon dioxide gas sensor was studied as a function of temperature and $CO_2$concentration in the Li$_2$ZrO$_3$ system. Lithium zirconate(Li$_2$ZrO$_3$) was synthesized by the heat-treatment of zirconia(ZrO$_2$)and Lithium carbonate(Li$_2$CO$_3$). The specimens were prepared both as bulk disk, 10mm in diameter and 1.0mm thickness, and thick films on an alumina substrate. Lithium zirconate readily responded to $CO_2$concentration from 0.1% to 100% in the range of 45$0^{\circ}C$ to $650^{\circ}C$. The sensitivity to $CO_2$ was dependent on the measuring temperature. Lithium zirconate(Li$_2$ZrO$_3$) decomposes into Li$_2$CO$_3$ and ZrO$_2$after the reaction with $CO_2$in the range of 45$0^{\circ}C$ to $650^{\circ}C$. Li$_2$CO$_3$ changes into Li$_2$O and $CO_2$ above $650^{\circ}C$. The material showed difficulty with reversibility and recovery. The optimum temperature for the highest sensitivity is around 55$0^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.35 no.5
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• pp.451-457
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• 1998

$Li_2$$ZrO_3$ powder which is one of the candidates of breeding materials for the fusion reactor was syn-thesized by a precipitation-combustion process. Although precipitates from the reaction between zirconium nitrate and citric acid were existed in a precursor solution. $Li_2$$ZrO_3$ could easily be obtained by using the mixed fuel of urea and citric acid in stoichiometric composition. The phases of as-synthesized powder con-sisted of $Li_2$$ZrO_3$ and small amounts of $Li_6$$Zr_2O_3$ and $Li_2$$ZrO_3$ The latter phases disappeared after the cal-cination at $1100^{\circ}C$ for 2 h. The primary particle size and the specific surface area of as-synthesized powders were smaller than 20nm and 10-14 $M^2$/g, respectively. The primary particle size of the precipitation-combustion synthesized powders was affected by the size of precipitates present in a precursor solution.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.535-539
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• 2006

Effects of alkaline additives on the $CO_2$ removal reaction have been investigated by a thermogravimetric analyzer. $Li_2ZrO_3$ was synthesized by soild reaction of $ZrO_2$ with $Li_2CO_3$ and then alkali chemicals were added to the synthesized $Li_2ZrO_3$ and then heat treatment was carried out. Addition of alkali chemicals enhanced the reactivity of $Li_2ZrO_3$ with the following order; $K_2CO_3>NaCl>LiCl>Na_2CO_3$, which were resulted from the formation of partially melted $Li_2CO_3$. SEM photographs showed the presence of melted state and the XRD results showed that the chemical states of added salts were not changed. Addition of NaCl caused the induction time of about 60 min at the initial reaction stage and the addition of $Na_2CO_3$ inhibited the decomposition of $Li_2CO_3$ at about $700{\sim}750^{\circ}C$.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.12
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• pp.1347-1352
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• 2005

[ $H_2S$ ] removal reaction using $Li_2ZrO_3/honeycomb$ has been carried out in a fixed bed reactor for the cleaning of syngas from the waste gasifier. $Li_2ZrO_3$ was synthesised using reagent-grade $Li_3CO_3$ and $ZrO_2$ with suitable amount of ethanol in a 1:1 ratio. And then $Li_2ZrO_3$ were calcined in air at $850{\sim}1000^{\circ}C$ for 14 h. The optimum condition of $H_2S$ removal reaction is around 20 wt% $Li_2ZrO_3$/honeycomb at 300 mL/min and $700^{\circ}C$. At this condition, removal amount of $H_2S$ was about 0.337 $g^{H_2S}/g^{sorbent}$. Addition of $K_2CO_3$, $Na_2CO_3$, NaCl and LiCl in the $Li_2ZrO_3$ remarkably improves the $H_2S$ removal capacity of modified $Li_2ZrO_3$/honeycomb up to 23%. Analyses of $Li_2ZrO_3/honeycomb$ sorbent by SEM and XRD showed that $Li_2ZrO_3$ was uniformly impregnated into honeycomb up to considerable amounts. Furthermore, the physicochemical properties of the sorbent did not vary much up to $1000^{\circ}C$.

• Journal of Electrochemical Science and Technology
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• v.9 no.3
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• pp.176-183
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• 2018

In this study, a $Li_2ZrO_3$ coated $Li[Ni_{0.8}Co_{0.15}Al_{0.05}]O_2$ (NCA) cathode was applied to an all-solid-state cell employing a sulfide-based solid electrolyte. Sulfide-based solid electrolytes are preferable for all-solid-state cells because of their high ionic conductivity and good softness and elasticity. However, sulfides are very reactive with oxide cathodes, and this reduces the stability of the cathode/electrolyte interface of all-solid-state cells. $Li_2ZrO_3$ is expected to be a suitable coating material for the cathode because it can suppress the undesirable reactions at the cathode/sulfide electrolyte interface because of its good stability and high ionic conductivity. Cells employing $Li_2ZrO_3$ coated NCA showed superior capacity to those employing pristine NCA. Analysis by X-ray photoelectron spectroscopy and electron energy loss spectroscopy confirmed that the $Li_2ZrO_3$ coating layer suppresses the propagation of S and P into the cathode and the reaction between the cathode and the sulfide solid electrolyte. These results show that $Li_2ZrO_3$ coating is promising for reducing undesirable side reactions at the cathode/electrolyte interface of all-solid-state-cells.

• Journal of the Korean Ceramic Society
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• v.18 no.3
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• pp.187-191
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• 1981

The effect of additions, $TiO_2$ and $ZrO_2$ as nucleant on the base glass which composition was determined to 0.97 $Li_2O-Al_2O_3-SiO_2$ has been investigated by means of D.T.A., X-ray diffraction and dilatation. $TiO_2$ and $ZrO_2$ as nucleant were added 0.06mole, in which ratios of $TiO_2$/$ZrO_2$ were varied 1/0, 2/1, 1/1, 1/2 and 0/1. The crystalline phases were appeared to $\beta$-spodumene as principal, $\beta$-eucryptite and $ZrO_2$ as secondary, regardless of nucleant variations. The crystallinity of the crystallized glass added $TiO_2$, $ZrO_2$ mixture as nucleant was higher than that of the glass added $TiO_2$ or $ZrO_2$ only. The crystallinity of the glass added $TiO_2$/$ZrO_2$ =1/1 was highest. Increasing the addition of $ZrO_2$, it has been observed that the crystal growing temperature became higher.

• Journal of the Korean Ceramic Society
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• v.43 no.5 s.288
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• pp.309-314
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• 2006

We synthesized lithium zirconate using solid-state reaction and analyzed thermal properties (TG/DTA) of starting materials and the synthesized one. When $Li_2ZrO_3$ powder was exposed to $CO_2$ environment at $500^{\circ}C$, 93% of the theoretical absorption weight was gained within 280 min with fairly high sorption rate. Almost all the absorbed $CO_2$ was generated by heating the sample to $800^{\circ}C$. We also investigated densification behavior of $Li_2ZrO_3$ under $CO_2$ environment. By sintering $Li_2ZrO_3$ at $760^{\circ}C$ using 2-step process, we obtained dense product, composed mainly of $Li_2ZrO_3\;and\;ZrO_2$, with relative density of 92%.