• Applied Chemistry for Engineering
• /
• v.20 no.2
• /
• pp.201-207
• /
• 2009

The hydrogenation reaction of methyl dodecanoate for the synthesis of 1-dodecanol has been carried out in the presence of a copper chromite catalyst. The catalysts were synthesized by ceramic method, co-precipitation, and improved co-precipitation method and the particles were characterized by SEM and XRD. Also, the products of the reaction were assigned by GC, GC/MSD and NMR. The particles synthesized by each method showed (1) a spherical shape with the size of 3.2 to $7.0{\mu}m$, (2) an agglomerated spherical shape with the size of 50 to 500 nm and (3) a spherical shape with smaller particle size, respectively. Especially, in order to control the size of particles, the particles were synthesized in various dispersant solutions as Span 80, polyacrylate, and polyethyleneglycols (PEGs). The particles synthesized in PEG (Mw = 4000) solution showed the smallest particle size of 30 to 50 nm and the regularity of the particle size distribution. Our experimental results elucidated that the activity of catalyst for hydrogenation increases with decreasing the size of catalyst particle. The highest yield of dodecanol in the hydrogenation reaction was 95.5% when copper chromite synthesized in the PEG solution was used as a catalyst in the optimized reaction condition.

• Journal of the Korean Applied Science and Technology
• /
• v.19 no.4
• /
• pp.251-257
• /
• 2002

Liquid-phase methanol synthesis via methyl formate using coal-derived syngas was carried out in a bench-scale(diameter 173 mm and dispersion height 1200 mm) slurry bubble column reactor(SBCR) Under the condition of $180^{\circ}$. 61 atm, 30 L/min, $H_{2}$/CO=2 and a slurry mixture of 2 kg of copper chromite and 0.5 kg of $KOCH_{3}$ suspended in 14 L of methanol, the per pass conversions of syngas is 6 %, maximum concentration of methyl formate 3.088 mol% and maximum synthesis, rate of methanol 0.8 gmole/kg ${\cdot}$ hr. It is a significant evidence that copper chromite powder as heterogeneous catalyst didn't active for the hydrogenolysis of methyl formate to methanol, resulting copper chromite powder was not efficiently suspended in a slurry mixture. To enhance the hydrogenolysis of methyl formate in liquid-phase methanol synthesis process, the designed SBCR have need to use the higher specific gravity solvent and/or decrease the catalyst particle size.

• Journal of the Mineralogical Society of Korea
• /
• v.28 no.1
• /
• pp.17-28
• /
• 2015

In order to study the mineralogical and chemical characteristics of copper slag, optical microscopy, SEM/EDS, EPMA, AAS and XRD analyses were carried out. In addition, sulfuric acid leaching experiments were performed to investigate the potential of the slag as a copper resource. It was confirmed that fayalite, chromite, bornite and chalcopyrite were contained in the slag. The slag mainly consisted of acicular fayalite and skeletal lath -euhedral chromite crystals. Also a very large amount of bornite and chalcopyrite grains were contained in the slag. The content of Fe and Cu in the slag was 18.37% and 0.93%, respectively. As a result of sulfuric acid leaching experiments, the leaching rates of Cu and Fe were increased through decreasing the slag particle size, increasing the sulfuric acid concentration and the leaching temperature. The maximum efficiency of Cu and Fe leaching were obtained under the conditions of particle size of 32 mesh, sulfuric acid concentration of 2.0 M, and leaching temperature of $60^{\circ}C$. Accordingly, it is expected that the slag could be available as a potential and alternative resource of metallic copper.

• Proceedings of the KAIS Fall Conference
• /
• 2010.05b
• /
• pp.957-960
• /
• 2010

본 연구에서는 중금속 크롬($Cr^{+6}$)이 포함된 흑색안료(Copper Chromite Black)를 공침공정을 이용하여 무독성의 Fe 화합물로 대체한 환경친화적인 블랙(흑색)안료를 개발하였다. 안료제조를 위하여 인체에 무해한 화합물($MnCO_3$, Fe(OH)$_3$, CuO)을 원료로 사용하였으며, 가스소성, Ring-Mill에 의한 습식분쇄 그리고 건조과정을 통하여 흑색안료를 제조하였다. 안료의 평가는 제품의 품질을 결정하는 색상과 착색력을 최우선으로 선정하여 색차계로 고찰하였다. 연구결과, 공침공정으로 제조한 원료를 $950^{\circ}C$에서 12시간 동안 가스소성을 한 후 건조와 분쇄공정(습식)을 거쳐 흑색안료를 제조하였을 때, 최적의 색 선명도, 착색력 및 입도($1{\mu}m$ 이하)를 가진 것으로 나타났다.