Stepwise Reduction Behavior of Molybdenum Trioxide Using Ammonia Gas

Om Shankar Dinkar; Hanggoo Kim; Kyoungkeun Yoo

doi:10.32390/ksmer.2026.63.4.417

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2026 Vol.63, Issue 4 Preview Page Next Page

Research Paper

Stepwise Reduction Behavior of Molybdenum Trioxide Using Ammonia Gas 암모니아 가스를 이용한 삼산화몰리브덴의 단계적 환원거동

31 August 2026. pp. 417-424

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Abstract

Ammonia recovered as a by-product of the metallic molybdenum production process was reused as a reducing agent for molybdenum trioxide (MoO₃), and its stepwise reduction behavior was investigated. During the reduction of MoO₃ to molybdenum dioxide (MoO₂), a conversion of 99.99% was achieved at 525°C for 30 min with an ammonia flow rate above 0.15 L/min, and XRD and SEM-EDS analyses confirmed the formation of pure MoO₂. In the subsequent reduction of MoO₂ to metallic Mo, an NH₃-Ar mixed gas alone yielded limited conversions of 65.62–75.97% at 700–725°C because of the formation of molybdenum nitride (Mo₄N₇) from nitrogen generated during ammonia decomposition. Introducing hydrogen into the gas mixture suppressed nitride formation, increasing the conversion to 99.81% at 800°C after 120 min, with XRD analysis confirming the formation of pure metallic Mo. These results demonstrate that ammonia volatilized during calcination can be effectively reused as a reducing agent, thereby improving process efficiency and reducing hydrogen consumption.

Keywords

molybdenum

molybdenum trioxide

molybdenum dioxide

ammonia

reduction behavior

몰리브덴 제조공정의 부산물로 회수되는 암모니아를 삼산화몰리브덴(MoO₃) 환원제로 재활용하고자 암모니아를 이용한 단계적 환원거동을 조사하였다. 이산화몰리브덴(MoO₂) 환원실험에서 525°C, 30분, 암모니아 유량 0.15 L/min 이상 조건에서 전환율 99.99%를 달성하였다. 암모니아-아르곤 혼합가스만으로 몰리브덴 금속 환원 시 700-725°C에서 전환율이 65.62-75.97%이었고, 이는 암모니아 열분해로 생성된 질소에 의해 몰리브덴 질화물(Mo₄N₇)이 형성되었기 때문이다. 수소를 추가한 혼합가스(NH₃, H₂, Ar)를 적용하자 800°C, 120분에서 전환율이 99.81%까지 향상되었으며 순수한 몰리브덴 금속상만 관찰되었다. 이는 하소공정에서 휘발되는 암모니아를 환원제로 활용할 수 있음을 보여주며, 공정효율 향상과 수소 사용량 절감에 기여할 것으로 기대된다.

키워드

몰리브덴

삼산화몰리브덴

이산화몰리브덴

암모니아

환원거동

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Information

Publisher :The Korean Society of Mineral and Energy Resources Engineers
Publisher(Ko) :한국자원공학회
Journal Title :Journal of the Korean Society of Mineral and Energy Resources Engineers
Journal Title(Ko) :한국자원공학회지
Volume : 63
No :4
Pages :417-424
Received Date : 2026-08-12
Revised Date : 2026-08-18
Accepted Date : 2026-08-19
DOI :https://doi.org/10.32390/ksmer.2026.63.4.417

Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

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