• Journal of the Korean Ceramic Society
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• v.37 no.10
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• pp.955-961
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• 2000

사티탄산칼륨을 리튬이온 전지의 양극재료로써 사용하고자 할 때 사티탄산칼륨의 합성 열처리 온도가 리튬이온 치환량에 미치는 영향에 대해 조사하였다. 사티탄산칼륨은 $K_2$O와 TiO$_2$의 몰 비를 1 : 3.91로 칭량하여 95$0^{\circ}C$, 100$0^{\circ}C$, 105$0^{\circ}C$에서 각각 합성하였다. 그 후, 사티탄산칼륨의 (Ti$_4$O$_{9}$ )$^{2-}$ 층간에 존재하는 $K^{+}$ 이온을 H$^{+}$ 이온으로 치환하고 이것을 다시 Li$^{+}$ 이온으로 치환하였다. 사티탄산칼륨의 합성 열처리 온도가 증가할수록 사티탄산칼륨의 (Ti$_4$O$_{9}$ )$^{2-}$ 층간의 거리가 감소했고 사티탄산칼륨의 길이가 증가했다. 95$0^{\circ}C$에서 열처리된 사티탄산칼륨의 리튬이온 치환량이 가장 많았다. 이는 상대적으로 낮은 합성 열처리 온도에서 사티탄산칼륨의 (Ti$_4$O$_{9}$ )$^{2-}$ 층간의 거리가 넓어져 리튬이온의 층간 이동이 쉬어졌고, 고온에서 열처리되어 길이가 긴 사티탄산칼륨에 비해 저온에서 열처리된 사티탄산칼륨은 길이가 짧아져 리튬이온이 (Ti$_4$O$_{9}$ )$^{2-}$ 층간으로 이동해 가는 거리가 짧아졌으며 아울러 짧은 사티탄산칼륨의 개수가 동일한 무게 당긴 사티탄산칼륨의 개수보다 많으므로 리튬이온의 치환량이 많아진다고 사료된다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.6
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• pp.329-337
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• 2019

We synthesized potassium titanates having splinter and plate shape and evaluated frictional and wear properties of brake pad using them as reinforcements in friction materials. For splinter-shaped potassium titanates, potassium tetratitanate (K₂O·4TiO₂, PT4) with plate shape was prepared, then K ion of the titanate was leached by acid to make potassium hexatitanate (K₂O·6TiO₂, PT6), which was transformed to splinter-shaped PT6 by thermal treatment at 800℃. Plate-shaped potassium magnesium titanate (K_0.8Mg_0.4Ti_1.6O₄, PMT) was prepared by adding Mg in the potassium titanate using KCl as a flux. Using PT6 and PMT as reinforcements in friction materials of brake pad, we evaluated frictional and wear properties using 1/5-scale dynamometer. According to dynamometer test results, both reinforcements shows similar friction coefficient and fade & recovery behavior to conventional material and plate-shaped PMT exhibits higher wear resistance than splinter-shaped PT6.

• Elastomers and Composites
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• v.35 no.3
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• pp.180-187
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• 2000

For the purpose of developing a new type of frictional material using scrap rubber in which rubber makes continuous phase, potassium titanate($K_2Ti_6O_{13}$) was synthesized and added to rubber matrix. Needle-typed $K_2Ti_6O_{13}$ powders were obtained through the flux method using KCI salt and excess $K_2CO_3$. It was also found that the powders should be surface-treated to enhance adhesion and 10 phr of epoxy be added for the physical properties of the rubber composite.

• Journal of the Korean Chemical Society
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• v.41 no.10
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• pp.535-540
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• 1997

Potassium carbonate reacts with silicon tetrachloride to form trichlorosilyloxy carbonylchloride which reacts subsequently with another molecule of silicon tetrachloride leading to phosgene eventually in chlorinated solvents. This in situ generated trichlorosilyloxy carbonylchloride or phosgene were found to be very effective for the chlorination of a wide variety of alcohols to the corresponding chlorides. Primary, secondary and benzylic alcohols were converted into corresponding chlorides when treated with silicon tetrachloride in the presence of potassium carbonate at room temperature.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.11a
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• pp.71-74
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• 1995

티타니아계의 흡착제로 최근 주목을 끄는 것은 티탄산칼륨 신소재를 들을 수 있다. 모서리의 chains sharing들과 b축을 따라서 TiO$_{6}$, 즉 8면체의 coner 결합으로 특징 지워지는 티탄산칼륨은 $K_2$O.nTiO$_2$로 표시되는 화합물로 플라스틱의 보강재나 단열재료 용도로 사용되었다. 공업재료로서 중요한 것은 n의 값이 2, 4, 6으로 각각 2티탄산칼륨(K$_2$Ti$_2$O$_{5}$), 4티탄산칼륨(K$_2$Ti$_4$O$_{9}$), 6티탄산칼륨(K$_2$Ti$_{6}$O$_{13}$)으로 불린다. 티탄산칼륨은 기계적 강도가 고강도재료 지르코이나에 해당하고 선팽창계수는 알루미나보다 작아 우수한 내열 및 단열 고강도재료이며 융막재, 이온교환재등으로 쓰인다. 층상구조의 티탄산칼륨을 산처리하여 칼륨을 추출하고 수소이온으로 치환한 결정질 티탄산칼륨 섬유(H$_2$Ti$_4$O$_{9}$.1.2~1.3$H_2O$)는 (H$^{-}$. H$_3$O$^{+}$)Ti$_4$O$_{9}$의 형태를 지니게 된다.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.3
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• pp.486-493
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• 2008

Safflower red colorants extracted by two solvents including the traditional ash solution and $K_{2}CO_{3}$ solution was used for dyeing cotton, ramie, viscose rayon, silk, wool, and nylon fabrics. The effects of extraction solvents on the reflectance, K/S value, and color properties of the dyed fabrics were investigated. Wash/dry cleaning and light colorfastness were evaluated. Reflectance curves of cotton, ramie, viscose rayon, and silk fabrics dyed with red colorants extracted by $K_{2}CO_{3}$ solution were similar, showing the maximum absorption at 520nm, to that of the dyed fabrics with red colorants extracted by ash solution. The reflectance curves of wool and nylon fabrics were different, showing the maximum absorption at 400nm. K/S values of dyed fabrics with red colorants extracted by $K_{2}CO_{3}$ solution were higher than that by ash solution with the exception of nylon. $L^{*},\;a^{*},\;b^{*}$, and $C^{*}$ of the dyed fabrics with red colorants extracted by $K_{2}CO_{3}$ solution were higher than that by ash solution except for $L^{*}$ of nylon and $b^{*}$ of viscose rayon. Color difference(${{\Delta}E}^*$) of the dyed fabrics between ash solution and $K_{2}CO_{3}$ solution increased in the order named as cotton, silk, ramie, viscose rayon, wool, and nylon. Regardless of extraction solvents, safflower red colorants produced RP color on cotton, ramie, and nylon, R color on viscose rayon and silk, and YR color on wool. Wash/dry cleaning fastness of the dyed fabrics was high above 3/4 rating but light fastness was very poor. It is considered that the use of $K_{2}CO_{3}$ solution instead of the traditional ash solution would be more effective in terms of color reproducibility and extraction process.

• Proceedings of the Korean Fiber Society Conference
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• 1996.04a
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• pp.138-140
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• 1996

• Applied Chemistry for Engineering
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• v.10 no.2
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• pp.177-182
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• 1999

The electrolyte was brought into contact with air and potassium carbonate concentration was measured with various contact time in order to check the effect of carbon dioxide in the air on zinc-air cell. The relationship between potassium carbonate concentration in electrolyte and battery capacity was also studied. The potassium carbonate concentration increased due to carbon dioxide absorption with increasing contact time with air, but the cell capacity linearly decreased with increasing potassium carbonate concentration in the electrolyte. The rate of carbon dioxide absorption was mainly affected by the pore size of hydrophobic membrane. Our study showed that adapting the pore of hydrophobic membrane decreased the loss of cell discharge performance due to the presence of carbon dioxide or water vapor in the atmosphere.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.11
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• pp.597-606
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• 2015

This work investigates the carbonation of KOH-dissolved methanol and ethanol solution systems carried out for $CO_2$ fixation. Potassium methyl carbonate (PMC) and potassium ethyl carbonate (PEC) were synthesized during the reaction in each solution as the solid powder, and they were characterized in detail. The amount of $CO_2$ chemically absorbed to produce the PMC and PEC precipitates were calculated to be 97.90% and 99.58% of their theoretical values, respectively. In addition, a substantial amount of $CO_2$ was physically absorbed in the solution during the carbonation. PMC precipitates were consisted of the pure PMC and $KHCO_3$ with the weight ratio of 5:5, respectively. PEC precipitates were also mixture of the pure PEC and $KHCO_3$ with the weight ratio of 8:2, respectively. When these two precipitates were dissolved in excess water, methanol and ethanol were regenerated remaining solid $KHCO_3$ in the solutions. Therefore, the process has the potential to be one of the efficient options of CCS and CCU technologies.

• Journal of Food Hygiene and Safety
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• v.14 no.3
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• pp.244-248
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• 1999

This study was carried out to determine the contents of sodium saccharin, sodium benzoate and potassium sorbate in danmooji, jangachi, puffed cereal, mixed beverages, carbonated beverages, fruit and vegertable juices (excepted unheated fruit and vegertable juices) and dried fishery products(seasoned) in the market. Sodium saccharin, sodium benzoate and potassium sorb ate were analyzed by HPLC at the wavelength of 215 nm with 0.05% ammonium phosphate dibasic acetonitril mobil phase(94 : 6), and recovery rates were 96.2-100.3%, 95.8-100.9%, 96.1-99.8%, respectively. The contents of sodium saccharin were N.D.-1234.8 mg/kg in danmoogi, jangachi, puffed cereal and mixed beverages and sodium benzoate in mixed beverages, carbonated beverages, fruit and vegertable juices were N.D.-663.2 mg/kg, and potassium sorbate in danmooji, jangachi and dried fishery products were N.D.-2725.2 mg/kg.