Resource utilization of titanium-containing slurry by selective extraction and leaching

2018 ◽  
Vol 115 (5) ◽  
pp. 504 ◽  
Author(s):  
Xiaoyan Xiang ◽  
Wentang Xia ◽  
Jianguo Yin

Resource utilization of titanium-containing slurry was realized by selective extraction and leaching. The results from the experiment confirmed that thistechnology was effective for recycling titanium and niobium from the slurry. During selective extraction, the extract solution with titanium content of 159.40 g/L was obtained after 3 stage-counter current extractions, and the titanium content of extracted residue could be reduced to 1.85 wt% which was much lower than the titanium content of titanium-containing slurry. The results of evaporation experiments indicated that CH2Cl2 in extracted residue could be separated and recovered effectively by evaporation and high temperature is beneficial for the whole process. Meanwhile, the titanium oxide and titanium oxychloride in extracted residue could also be transformed into TiCl4 and recovered by evaporation as the evaporation of dichloromethane in extracted residue. The beneficiation of niobium could be achieved when the evaporated residue was leached with diluted hydrochloric acid, the results of leaching test showed that more than 97% of the aluminum in evaporation residue was dissolved, while, only 1.3% of the niobium was leached. Finally, niobium concentrate with Nb2O5 content of 76.39% was obtained by washing the leaching residue with dilute ammonia water.

Author(s):  
Wei Huang ◽  
Eric Million ◽  
Kelvin Randhir ◽  
Joerg Petrasch ◽  
James Klausner ◽  
...  

Abstract An axisymmetric model coupling counter-current gas-solid flow, heat transfer, and thermochemical redox reactions in a moving-bed tubular reactor was developed. The counter-current flow enhances convective heat transfer and a low oxygen partial pressure environment is maintained for thermal reduction within the reaction zone by using oxygen depleted inlet gas. A similar concept can be used for the oxidation reactor which releases high-temperature heat that can be used for power generation or as process heat. The heat transfer model was validated with published results for packed bed reactors. After validation, the model was applied to simulate the moving-bed reactor performance, through which the effects of the main geometric parameters and operating conditions were studied to provide guidance for lab-scale reactor fabrication and testing.


2009 ◽  
Vol 289-292 ◽  
pp. 69-75 ◽  
Author(s):  
S.Y. Brou ◽  
G. Bonnet ◽  
Jean Luc Grosseau-Poussard

TiAl, TA6V and titanium coupons were treated by a phosphoric acid solution by dipping. They were then submitted to a heat treatment and, in the case of TiAl and TA6V, to high temperature discontinuous oxidation under laboratory air. The H3PO4 treatment allowed to decrease the mass gains for TiAl and TA6V, in particular during the first 100 hours. XRD analyses demonstrated for the three substrates the formation of a pyrophosphate layer during the heating period. This pyrophosphate evolved towards TiO2 with oxidation time increase, quicker for smaller aluminium content (or higher titanium content) in the metallic substrate. The decrease of mass gains was attributed to a diffusion barrier effect of the pyrophosphate layer as long as it was present.


1995 ◽  
Vol 22 (5) ◽  
pp. 783 ◽  
Author(s):  
DJ Batten ◽  
CA Mcconchie

Buds of potted plants of the terminal flowering tree species lychee (Litchi chinensis) and mango (Mangifera indica) forced to begin growth at high temperatures (florally non-inductive) and then transferred to low temperatures produced inflorescences, so the whole process of floral induction can occur in growing buds. Floral initials were visible in lychee within 39 days of transfer to low temperature and 30 days in mango, indicating that floral induction occurs relatively quickly in both species. In most cases where plants were transferred to winter ambient temperatures for floral induction, pre-activated (growing) buds flowered more consistently than buds that were dormant at the time of transfer. If the buds were small when plants were transferred from high temperature to low temperature, leafless inflorescences formed. If buds were a little larger, leafy inflorescences formed, with leaves basally and flowers terminally. If the buds were larger again, the shoots were purely vegetative. All these observations are consistent with floral induction occuning while the bud is growing and provide for much improved experimental systems for studying the physiology of floral induction in species such as lychee and mango.


2002 ◽  
Vol 2002 (0) ◽  
pp. 257-258
Author(s):  
Yasuo Koizumi ◽  
Masanori Tukudo ◽  
Manabu Arai ◽  
Naoki Sakamoto ◽  
Hiroyasu Ohtake

2013 ◽  
Vol 743-744 ◽  
pp. 713-719
Author(s):  
Dong Zhu Ma ◽  
Hong He ◽  
Jian Li ◽  
Li Yun Song ◽  
Lian Jie Guo ◽  
...  

The effects on CH4 and N2 separation performance of coconut shell charcoal by high temperature roasting were studied. Results indicate that the surface area increased firstly and then decreased with the increasing of the roasting temperature, and it is found that surface area of roasting 4 hours is higher. Furthermore, the experiment focused on the effect of high temperature roasting on activated carbon adsorption volume and separation coefficient. It is obvious that the adsorption volume increases earlier and then decreases with the increasing roasting temperature, and there are obvious turning points to adsorption volume of CH4 and N2. Comparing various roasting time, it is found that adsorption volume in 4h is greater than that in 1h and also in 6h in the whole process. Separation coefficient decreases with increasing roasting temperature. When the temperature is higher than 800 , separation coefficient decreased rapidly. Considering the adsorption volume and separation coefficient, roasting 4 hours at 600 is selected for industrialized production.


1992 ◽  
Vol 590 (2) ◽  
pp. 289-296 ◽  
Author(s):  
Katsunori Watabe ◽  
Hisashi Kanda ◽  
Katsuya Sato ◽  
Toshiyuki Hobo

Sign in / Sign up

Export Citation Format

Share Document