말레이지아만 Cassiterite를 수소로 환원함에 있어 개스류량, 온도, 입도의 영향 및 석회와 규사를 첨가하여 그 환원특성을 조사하였다. 환원율은 열천평에 의하여 기록되는 배소감량으로 측정하였고 환원후는 광학현미경 및 엑스선 분석을 통하여 조사한 결과 다음과 같은 결론을 얻었다. 1. 수소의 유량은 일정한도량 이상에서는 환원율에 별로 영향을 주지 않는다. 2. 입도는 미세할수록 환원이 잘되며 Kinetic에 관한 식 r_0(1-(1-R)^(1/3)) =Kt에 잘 맞는다. 3. 온도가 상승할수록 환원속도는 급격히 빨라지며 수소에 의한 환원의 활성화 에너지는 18.2Kcal/mole 범위이다. 4. 석회나 규사 등의 첨가물은 환원성을 악화시킨다.

Reduction of Malay cassiterite by hydrogen gas has been carried out to investigate the effects of hydrogen flow rate, temperature, cassiterite size, and addition of lime and silica. Reduction degree was determined by thermal balance and the reduced cassiterite was examined with microscope and X-ray diffraction. The results from this experimental work were summarized as follows. 1. Reduction was accelerated with increased hydrogen flow rate, but not so much affected above certain limit. 2. The finer cassiterite size was the higher reduction rate and the kinetic equation, r_0(1-(1-R)^(1/3)) =kt, was applied well to the reduction of cassiterite. 3. As temperature was raised, reduction speed was increased, and the activation energy for the hydrogen reduction of Malay cassiterite was 18.2 Kcal/mole. 4. Addition of lime or silica to cassiterite inhibited the reducibility of the ore.