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Flotation separation of wolframite from quartz using N-oleoyl sarcosine acid as collector

Xian-Ping L., Feng B., Xianwen Z., Li-Yying L., Zheng-He X.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 1

34--41

EN

In this study the collecting power of N-oleoyl sarcosine acid towards wolframite and quartz was studied using flotation. The adsorption mechanism was also discussed based on the results from adsorption experiments, zeta potential measurements and infrared spectroscopy study. The flotation results showed that N-oleoyl sarcosine acid showed a good collecting power towards wolframite, and the optimal flotation pH = 7 was obtained. However, the collecting power of N-oleoyl sarcosine acid towards quartz was weak. Therefore, the flotation separation of wolframite from quartz can be performed using N-oleoyl sarcosine acid as a collector. The adsorption tests and electrokinetic studies showed that N-oleoyl sarcosine acid adsorbed only on the wolframite surface. Additionally, the results from the infrared spectroscopy study confirmed that N-oleoyl sarcosine acid is adsorbed on the wolframite surface, and the metal complex (ferriccarboxylate) maybe the major adsorbed species.

2

Role of sodium hexametaphosphate in flotation of a nickel ore

Feng B., Wang P., Lu Y., Feng Q.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 1

170--181

EN

In this work, a role of sodium hexametaphosphate (SHMP) in the flotation performance of a nickel ore was studied and mechanism was discussed in detail. The results showed that the presence of lizardite interferes with the flotation performance of pentlandite. The adsorption of SHMP at the lizardite/solution interface and the removal of magnesium ions from lizardite surface overcompensated the positive charge on the lizardite particle, and made its zeta potential negative. The interaction between lizardite and pentlandite changed from attractive to repulsive in the presence of SHMP. Thus, the addition of SHMP made the mixed sample of pentlandite and lizardite more dispersed, and significantly reduced the adverse effect of lizardite on the flotation of pentlandite. However, when the content of lizardite in the mixed ore was increased, the effect of SHMP weakened. Therefore, in flotation of a nickel ore containing a large amount of lizardite (46% w/w), SHMP usage is not suitable at the roughing stage due to the fact that lizardite in the pulp will consume most of the SHMP, and hence the removal of lizardite slimes from pentlandite surface become impossible. Based upon the results, SHMP usage is found to be suitable at the cleaning stage to improve the grade of concentrate.

3

Influence of Processing Techniques on Mechanical Properties and Impact Initiation of an Al-PTFE Reactive Material

Feng B., Fang X., Li Y.-C., Wu S.-Z., Mao Y.-M., Wang H.-X.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 4

989--1004

EN

Reactive materials (RMs) or impact-initiated materials have received much attention as a class of energetic materials in recent years. To assess the influence of processing techniques on mechanical properties and impact initiation behaviors of an Al-PTFE reactive material, quasi -static compression tests and drop-weight tests were performed. Scanning electron microscopy (SEM) was used to identify the characteristics of the interior microstructures of the Al-PTFE samples. A sintering process was found to transform Al-PTFE from a brittle to a ductile material with an increased elasticity modulus (from 108-160 MPa to 256-336 MPa) and yield stress (from 12-16 MPa to 19-20 MPa). Increasing the molding pressure from 36 MPa to 182 MPa increased the elastic modulus of all Al-PTFE samples and also the yield stress of unsintered ones. Unsintered samples in general required less energy to initiate than sintered ones. As the molding pressure increased, the impact initiation energy for sintered Al-PTFE fell from 96 J to 68 J, whereas the initiation energy for unsintered Al-PTFE rose from 68 J to 85 J. PTFE nanofiber networks observed in sintered samples formed under the higher molding pressures could contribute to the opposite trends observed in the impact initiation energy of unsintered and sintered Al-PTFE samples.

4

On the distance between adjacent zerores of solutions of first order neutral differential equations

Zhou Y., Yu Y., Feng B.

Demonstratio Mathematica

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1999

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Vol. 32, nr 1

31-40