• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.1
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• pp.1-7
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• 2004

The precipitation of ultra fine ammonium perchlorate(UFAP) crystals from the N-methyl pyrrolidone(NMP) solutions of ammonium perchlorate(AP) was studied. The characteristics of the precipitated crystals were investigated by means of scanning electron micrograph(SEM), X-ray diffraction(XRD), and thermogravimetric analysis(TGA). When chloroform, methylene chloride and toluene were the precipitants, the product crystals had a mean particle size less than 2$\mu\textrm{m}$. The crystallographical property and thermal decomposition behavior of the prepared UFAP were almost the same as those of the commercial AP.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.5
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• pp.352-358
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• 2014

The feasibility of perchlorate reducing-bacteria isolated from the sludge of an anaerobic digester was determined using ammonium perchlorate in aqueous medium. Growth kinetics of the two perchlorate reducing bacteria including Rhodococcus sp. YSPW01 and YSPW02 were investigated using acetate as the electron donor in batch experiment. The growth of YSPW01 and YSPW02 reached a steady-state at 26 and 9 h, respectively. The initial perchlorate concentration was completely reduced within 8 and 7 h by YSPW01 and YSPW02, respectively. The reduction rates were 2.1 and $15mg\;L^{-1}h^{-1}$ for YSPW01, and 3.2 and $15.5mg\;L^{-1}h^{-1}$ for YSPW02, at 1:1 and 5:1 ratios of acetate:perchlorate (w:w), respectively. In this study, the bacteria Rhodococcus sp. YSPW01 and YSPW02 demonstrated a potential for the perchlorate reduction, which could be further investigated for development of an efficient strategy to treat the perchlorate contaminated waters.

• Analytical Science and Technology
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• v.26 no.1
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• pp.11-18
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• 2013

Perchlorate ($ClO{_4}^-$) is the material that is used as propellants of rockets and material of explosive as a form of ammonium perchlorate salts. Ammonium perchlorate solution of high concentration is recovered from expired rocket through demilitarization process by the water-jet method. If people take perchlorate in food and water, it interferes with adsorption of iodide which is the substance needed to synthesize thyroid hormone in the thyroid gland. It has an bad influence upon disturbing pregnancy and synthesis of growth hormone. So the effective method is necessary to remove perchlorate anion in water. By considering economic aspect, we studied effective desorption (regeneration) of perchlorate anion from adsorbent with studies on removal and adsorption of perchlorate anion. Desorption experiment was conducted as batch type. Depending on various conditions (concentration, pH, cation anion form) elution, we evaluated amount, efficiency of desorption(amount of adsorption/desorption ${\times}$ 100). Also, research confirmed the efficiency of mixed resins between anion exchange resin and activated carbon and expected synergic effect from advantages of both adsorbents.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.460-463
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• 2011

Different kinds of solid rocket motors manufactured for various aim have their own shelf life. So they must be done away if not used. In general, ammonium perchlorate(AP) has used in the process of solid rocket motors, which is environmental pollutant. Out-burning and out-detonation were usual in the past, but they polluted the surrounding environment and raised safety issues. As an alternative to resolve these, water-washout process to separate the propellant from rocket motors and an eco-friendly way for recovering AP are studied in this paper.

• Journal of the Korean Applied Science and Technology
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• v.25 no.1
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• pp.65-72
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• 2008

The ion exchangers supported on silica gel containing primary, secondary, or tertiary amine groups show a behaviour that is weakly acidic, while the quaternary salts are strongly acidic. These properties change according to the hydrophilicities of the modifier functional groups. Ammonium salt derivatives supported on silica gel were prepared from silica modified with 3-Aminopropyltriethoxysiliane and N-3-(Trimethoxysilyl)propylehtylene diamine. The preparation and the ion exchange properties of two systems were discussed. Two systems have different hydrophilicities and contain ammonium chloride derivatives of 3-amminopropyltriethoxysilane and N-3-(triehtoxysilyl)propyl ethylene diamine supported on silica gel, $SA^+/Cl^-$ and $SA^+/Cl^-$, respectively. The high affinity to perchlorate ion presented by the $SA^+/Cl^-$ through the equilibrium studies of ion exchange led us to its application as an ion selective electrode for the perchlorate ion. The determination of the perchlorate ion in the presence of other anions and in complexes is very difficult. Few analytical methods are available and most of them are indirect. Both materials showed potential use as an ion exchanger; they are thermically stable, achieve equilibrium rapidly in the presence of suitable exchanger ions, and are easily recovered.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.109-114
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• 2013

The effects of aluminum nanoparticles (AlNs) on the thermal decomposition of ammonia perchlorate (AP) were investigated by DSC, TG-DSC and DSC-TG-MS-FTIR. Addition of AlNs resulted in an increase in the temperature of the first exothermic peak of AP and a decrease in the second. The processing of non-isothermal data at various heating rates with and without AlNs was performed using Netzsch Thermokinetics. The dependence of the activation energy calculated by Friedman's isoconversional method on the conversion degree indicated the decomposition process can be divided into three steps. They were C1/D1/D1 for neat AP, determined by Multivariate Non-linear Regression, and changed to C1/D1/F2 after addition of AlNs into AP. The isothermal curves showed that the thermal stability of AP in the low temperature stage was improved in the presence of AlNs.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.4
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• pp.298-305
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• 1998

The PVC membrane electrode for measuring perchlorate ion was developed by incorporating various quaternary ammonium sallts. The effect of chemical structure, the content of active material, the kind of plasticizers, and the membrane thickness on the electrode characteristic such as the linear response range and Nernstian slope of the electrode were studied. It was obtained that the effect of the chemical structure of an active material on the electrode characteristics was improved with increasing the alkyl chain length of the quarternary ammonium salts in the ascending order of Aliquat 336P, TOAP, TDAP, and TDDAP. The optimum membrane composition was 9.09wt% of TDDAP, 30.3wt% of PVC, and 60.6wt% of plasticizer(DBP). And the optimum membrane thickness was 0.45mm at this composition. Under the above condition, the linear response range was $10^{-1}~1.2\times10^{-6}$M, and the detection limit was $5.1\times10^{-7}$M with the Nernstian slope of 57mV/decade of activity of perchlorate ion. The electrode potential was stable within the pH range from 4 to 11. The selectivity coefficient was as shown below: $SCN^->I^-NO_3^->Br^->ClO_3^->F^->Cl^->SO_4^{2-}$

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.178-185
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• 2019

Three spherical quaternary composites composed of metal/metal oxide/high explosive/oxidizer were prepared by a crystallization/agglomeration process. From the characteristics of composites by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), the shortening of the decomposition zone of high explosives in the quaternary composite was observed, which may be attributed to the autocatalytic reaction caused by $ClO_2$ or HCl which are ammonium perchlorate (AP) degradation products. The activation energy analysis showed that the activation energy abruptly decreases at the end of the decomposition zone of high explosives, and it was considered to be caused by $HNO_2$ which is common in decomposition products of high explosives. The activation energy predicted from complex pyrolysis results by the distributed activation energy model (DAEM) showed much better in accuracy than those by model-fitting methods such as Kissinger-Akahira-Sunose and Flynn-Wall-Ozawa models.

• Journal of the Korean Chemical Society
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• v.41 no.12
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• pp.661-665
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• 1997

Recently ADN was disclosed to replace AP or AN as a solid oxidizer. 3-N,N-Dinitraminopropanitrile, a key intermediate in the preparation of ADN, was synthesized from bis(2-cyanoethyl)amine by the sequence: nitration of bis(2-cyanoethyl)amine followed by decyanoethylation by base and the second nitration with NO2BF4. 3-N-Nitro-bis(2-cyanoethyl)amine could also be obtained by the oxidation of the corresponding N-nitroso compound.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1999.04a
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• pp.20-20
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• 1999

질산 암모늄(ammonium nitrate, AN)은 고체 추진제의 산화제로 사용하기에는 산소 함유량이나 밀도가 과산화염화 암모늄(ammonium perchlorate, AP)보다 불리하여 로켓 추진기관용으로는 널리 사용되지 않았지만 가스발생기용 추진제의 원료로 소량 사용되어 왔었다. 그러나 근래에 와서 군사 무기에 대한 안전 규정이 강화되면서 화재나 폭발에 대한 위험도를 낮추고, 특히 연소 기체에서 유독성 염화수소의 발생량을 줄이기 위해서는 AP나 RDX, HMX와 같은 산화제를 AN으로 대체 사용하는 연구를 많이 수행하고 있다.