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By S. L. Zheng

The compound material of Nano-TiO2 Supported on the diatomite was prepared by the hydrolytic method with purified diatomite and TiCl4. The compound material was characterized by SEM, XRD, TEM, EDX, XPS, and the application test of the compound material was studied. The characterization test results showed that the Nano-TiO2 was coated on the surface of diatomite, the crystal of TiO2 is anatase, and the average crystal size is 12 nm. The pore diameter was reduced, but pore volume and surface area of the compound material are increased after Nano-TiO2 Supported on the diatomite. The application test results for treating coking waste water and formaldehyde gas show that the compound material of Nano-TiO2 / diatomite has adsorption and photo-catalytic function and strong degradation performance for phenol and formaldehyde.

Jan 1, 2014

By S. Castro, L. Gutierrez

"Mining operations are often located in remote arid environments with limited access to fresh water. Shortage of fresh water in such cases makes it necessary to use seawater in mineral processing plants. Such plants treating Cu- Mo sulfide ores in seawater have been fully operational in Chile (e.g. Las Luces, Centinela). In many cases process waters used in commercial flotation plants (e.g. Mt Keith in Western Australia) are even more concentrated electrolyte solutions than seawater. This paper is an attempt at classification of the flotation operations carried out in process waters that are concentrated electrolyte solutions.INTRODUCTIONAccording to Gleick (1966), of the total Earth’ water resources 97.5% is in the oceans and ice caps, and thus only about 2.5% is fresh water. Shortage of fresh water in many parts of the world makes it necessary to use seawater in mineral processing operations. The existing commercial operations using seawater as well as recent research projects that deal not only with sulfide ores but also with apatite ores provide a lot of information that can now be generalized. The progress that has been made in this area is reviewed and based on this information an attempt is being made at classifying the flotation operations carried out in highly concentrated electrolyte process waters.SALT FLOTATIONFlotation in highly concentrated electrolyte solutions was studied by Klassen (Klassen, 1963). He reported that hydrophobic, bituminous coals, could float in salt solutions without addition of any other flotation agents. The process is referred to as salt flotation. Other inherently hyhrophobic minerals (e.g. talc, graphite, sulfur, etc.) were shown to behave similarly (Klassen and Mokrousov, 1963)As Figure 1 shows, some coals float quite well in solutions of Na2SO4, NaCl and NaNO3 (Klassen, 1963). While there are differences between the tested salts (explained by different foamabilities of these solutions) all the tests indicate that only bituminous coals float well in concentrated electrolyte solutions. 0.3 M solutions are quite sufficient to initiate a good and very fast flotation. If wettability of various coals is compared it becomes obvious that these well floating coals are very hydrophobic bituminous coals (Figure 2)."

Jan 1, 2018

By Osvaldo A. Bascur

One of the most vigorous of the continuous improvement methodologies is Six Sigma. While usually associated with improving manufacturing and product quality, leading manufacturers are using it to improve their extended supply chain and logistics capabilities. At the same time they are improving reliability, some companies have cut hundreds of millions of dollars of fat out of their supply chain. Mine to Mill optimization is a transformation of culture from processing tons to processing a quality feed size distribution which reduces the overall operational costs and add the highest value to the mine. This is not a constant endeavor. As such, a dynamic performance monitoring and diagnosis is necessary. We will review a systemic way to performance improvements and avoiding metal losses from the blast to the metals. We show the requirements of using raw data to analysis the data to define operational maps which provide assistance to run the mine and mill. A case study is provided with the mine and mill data was integrated combining process control and quality information resulting in reduction of water and energy consumption while improving the overall value of the mine. The results of reengineering the current system with this SIX SIGMA Strategy had the following results: an increase of ore milling: 4.6% decrease of mil power: 3.9%, decrease of fresh water consumption: 6.8%, with a total of net profits: US$ 31.8 million, the PI System infrastructure contribution: US$ 7.95 million. These estimates were for the period 2009/04/04 to 2009/12/31.

Sep 1, 2012

By M. Bergerman

Sossego was the first Vale SAG mill operation to process copper-gold ore. It is located in Para state, south east of Amazon region in Brazil. The comminution circuit was designed to treat 41 000 metric tons per day comprising primary crushing, one 11.6 m SAG mill operating in closed configuration with cone crushers, followed by two 6.7 ball mills. In the first three years of continuous operation Vale investigated alternatives for obtained improved performance of the circuit by investigating operating conditions, mainly focusing on SAG mill. A number of actions were then implemented, which resulted in significant increase in overall production. Vale then decided to further assess the performance of the comminution circuit as a function of ore characteristics. A comprehensive ore characterization program was then conducted, together with the calibration of mathematical models on the basis of surveys carried out at the industrial circuit. The simulator was then used to predict the production level associated to each ore type, as well as to establish the optimized circuit configuration and tailored operating conditions. The ongoing validation program is planned to consolidate the selected strategy, as well as showing the benefits in adopting such indices in mine planning, as opposed to rather simplistic approaches. This paper describes in detail the main aspects of optimizing the industrial circuit performance, as well as the successful method for predicting the production as a function of ore characteristics.

Jan 1, 2014

By Diana Drinkwater, Tim Napier-Munn

"This paper argues that, although specialist mineral engineering expertise is essential for the efficient design and operation of mineral processing plants, the environment in which these skills are supplied to the industry has changed forever, and not for the better. Most of the mineral engineering programmes in western universities have died or are dying. The long-service mine site mentors have gone, operations are run on a staffing shoestring so that there is no longer the time (or inclination) for considered decision-making, and the FIFO model has discouraged continuity of optimisation projects and communication between professionals. At the same time the technical challenges of designing and operating effective process plants are increasing. These trends are not going to be reversed any time soon, if ever. The ability to run efficient mineral processing operations has been materially compromised as a consequence. We propose that well-designed professional development can help to recover this situation, and it can be done easily and cheaply. The workplace is the best environment for such skills development. Professional development training should be integrated with normal duties throughout the early years of a graduate’s service (and probably beyond), and the cost should be regarded as non-discretionary expenditure for the business. If such programmes are properly resourced and managed and extended over longer time periods, there will be a measureable rise in the level of technical understanding and competence within companies and a resulting beneficial impact on resource utilisation and thus shareholder value. The paper outlines some of the approaches that we believe will work, and the benefits that we expect will accrue."

Jan 1, 2014

By X. M. Chen

The selection of leach reagent mainly according to the ratio of useful mineral to gangue in mineral raw material and the structure of mineral raw material. Besides that the price of reagent, the capability of reagent decomposing mineral and its causticity on equipment is also supposed to be in regard. On common conditions, the scandium content in mineral raw material is low, even Sc concentrate of specimen-Yunnan rare earth ore which contain Sc used in this experiment only is 148 g/t. Moreover, in enlarging scale experiments the content of scandium in leach liquid is only 3.6g/t, meanwhile various and complicated impurity existing in it. At present, both domestic and abroad has succeed in enriching scandium from vitriol solution, while enriching scandium from hydrochloric acid only has been studied in some minority units, which is not reported to be practical in industry. Therefore, this item offer a new research issue on Sc?s extract, which is as well as the task of this research. Spectrum analysis, chemic component analysis and scandium content have been made in main mineral measurement on rare earth with Sc in the paper. Based on characters of sample, select hydrochloric acid, vitriol and nitric acid as leach reagent and make different blueprints to accomplish the experimental research about selecting leach reagent. In the aspect of rare earth leach scandium leach density is researched, leach liquid to solid rate, leach temperature, leach time, leach granule rate and leach solution. This experiment claims that in the optimal experimental ambience, leach rate of vitriol is 58.18%, the leach rate of nitric acid is 50.73% and the leach rate of hydrochloric acid is 59.34%. Among them, hydrochloric acid has the best effect, therefore this experiment choose it as the leach reagent.

Jan 1, 2014

By Robin J. Batterham

Alumina demand is steadily climbing around the world and is likely to continue to do so for many years. In such a commodity industry, the question arises as to what effort should be expended on innovation, given that for an individual company, the drivers of change are cost and quality as the market demand is essentially assured. This is of course a long-term view. The current conditions are less attractive. In this presentation, we review the broad issues that are considered targets for collaborative development by the industry as recently updated in the alumina industry roadmap published by the International Aluminium Institute in 2010. While they cover areas such as ?mine rehabilitation, residue management and use, alumina production from high sulfur bauxite, bauxite beneficiation, energy efficiency and alternative technologies for alkali and alumina recovery from bauxite residues,? it must be remembered that each refinery is different in terms of the feed material and the circumstances of waste disposal. Of particular interest is the more competitive area of breakthrough technologies. In the presentation, we will consider a range of opportunities that could transform the industry, from relatively near term possibilities such as bauxite activation through possibilities to eliminate crystallization as currently practiced to complete alternatives, such as the use of hyperaccumulating plants. Against this optimism, some of the realities that hold back breakthrough innovation will be presented for discussion.

Sep 1, 2012

By Sushanta Majumder

The physico-chemical characteristics of raw materials used for the production of iron ore pellets have a strong influence on the productivity of pelletization operations and on the quality of pellets. Since iron ores from different sources are used for making iron ore pellets and since the quality of the ores varies with time, there is a need to optimize and control pellet plant operations on a regular basis to achieve optimum productivity while maintaining pellet quality within the desirable specifications. In order to achieve this objective, a model-based on-line optimization system was implemented on two industrial scale induration furnaces. The optimization system consists of a rigorous mathematical model of the induration process, a model for the permeability of the bed of pellets, a statistical model for the quality of iron ore pellets and an optimization module based on sequential quadratic programming. The rigorous model is tested on-line using the wind-box temperature available real-time. The process was optimized to enhance induration furnace productivity for the given constraints on pellet quality parameters such as the cold compressive strength (CCS) and Tumble Index (TI), and other equipment design parameters. Process variables such as induration machine speed, cold air flow rate and hood temperature profile were used as the optimization variables. The on-line optimization system was successfully implemented in two industrial induration furnaces and lead to enhanced productivity. Details of the on-line optimization system and results of process optimization will be presented.

Sep 1, 2012

By John Ralston, Jona Addai-Mensah, Patience Mpofu

The flocculation and dewatering behaviour of kaolinite (non swelling) and smectite (swelling) clay dispersions has been investigated using hydrolysable metal ions Mn(II) and Ca(II) and anionic polyacrylamide-acrylate copolymer (PAM) at pH 7.5 and 10.5. A pH-dependent, specific metal ion adsorption behaviour, accompanied by a marked reduction in particle zeta potential and slurry shear yield stress, was observed to have a profound influence on the colloid stability of both types of clays. Due to the differences in the cation exchange capacity, the smectite clay dispersion required a higher amount of metal ions than kaolinite dispersion to produce similar effects. The adsorption density of the anionic PAM at the negatively charged clay particle surfaces correlated well with metal ion hydrolysis and adsorption behaviour, all of which had a strong effect on slurry settling rate and extent of consolidation. At pH 7.5 where Mn(II) ions hydrolyse, metal ion and flocculant adsorption densities were both greater in the presence of Mn(II) than Ca(II) ions. At pH 10.5, however, where Ca(II) ions begins to hydrolyse, higher adsorption densities were observed for Ca(II) ions in comparison with Mn(II) ions, as the latter hydrolysed completely and precipitated. The metal ion mediated flocculant adsorption led to improved hydrogen bond driven particle bridging and facilitated charge neutralisation flocculation mechanisms which significantly enhanced the dewaterability of both clay dispersions.

Jan 1, 2003

By R. K. Logric

Bor flotation tailings are very interesting from two reasons: first, is having due value presently, and second represent serious pollutant into this region of Balkan. This paper is only one small part of investigation about processing of valuable minerals from tailings, and desulphurization of this biggest pollutant in the same time, by refloating. The main objective of this work is to pay attention on this problem for resolve greatest environ-mental problem of Serbia and Balkan in the nearly future. Bor is potential regional risk spot, since that failure of its tailings dams would release high amounts of toxic materials that would reach the Danube River. The basic goal of this experimental investigation was finding some possibility for flotation tailings treatment by classical froth flotation. In order was obtained material effect through copper recovery, and environmental protection by moving the rest of reprocessing into the safe place. The work present obtained results of laboratory tests in two laboratories: laboratory of mineral and recycling technology at the faculty in Bor, and laboratory of department of mineral processing of ITNMS in Belgrade.

Jan 1, 2014

By G. C. Li

Gold extraction using iodide leaching from refractory carbonaceous gold ores was studied. Thermodynamic analysis of iodide leaching chemistry had been carried out. Eh-pH diagram of Au-I2-I--H2O leaching system showed that the coordinating active forms from iodides were I3- and I-, while the major coordinate compound formed during iodide leaching was AuI-. For leaching parameters optimization, technological parameters such as I2 concentration, I2 :I- ratio, oxidation assisting agents, liquid/solid ratio, and leaching duration were studied. The leaching results showed that the average Au leaching rate reached 91% and 92% for oxidized ore and roasted primary ore respectively. Leaching process proceeded in weekly acidic or neutral slurry at ambient temperature; the leaching duration was 4 hours. After that gold was extracted from the pregnant liquor by activated carbon adsorption ? desorption ? electrowinning process. Gold recovery was over 93% in the adsorption process, while the gold recovery in electrowinning process was about 95%, provided that the initial gold concentration is 40mg/L or larger. For iodine regeneration it is enough to add hydrogen peroxide in excess into the filtrate after gold electrowinning, all the iodides existing in the solution in any forms would be precipitated in the form of elemental iodine.

Jan 1, 2014

By Daniel Saramak

"Issues concerning effectiveness of the high-pressure comminution process in technological circuits of copper ore treatment were presented in the paper. Crushing processes taking place in high-pressure grinding rolls devices (HPGR) are currently one of the most efficient methods of hard ore size reduction in terms of the energy consumption. The HPGR products are characterized by a fine particle size and the micro-cracks formation in individual particles, which appear in downstream grinding processes, decreasing their energy consumption. The purpose of this paper was to analyse the effectiveness of a ball mill grinding process depending on the changeable conditions of run for the HPGR crushing process. The research programme carried out included crushing tests in the laboratory scale HPGR device at various settings of the operating pressure volume and selected qualitative properties of the feed material (i.e. particle size distribution). Particle size distribution analyses of all HPGR products were performed and in the next stage the material was a feed to the ball mill grinding process. Grinding process kinetics were investigated through the determination of mass recoveries of individual particle size fractions after defined grinding time intervals. The models, defining the grinding process effectiveness as a function of changeable conditions of HPGR process run, were determined on the basis of obtained results. Based on these models the optimal grinding time in a ball mill was specified which is, in turn, the basis for optimization of operation of the technological comminution circuits for a given material type. The obtained results proved that the application of HPGR devices in a given copper ore comminution circuit may improve the effectiveness of the downstream grinding process which leads to improvement of the entire circuit work efficiency through decreasing the process energy consumption and enhancing product size reduction."

Jan 1, 2014

By Carmina Quintanar, Mario Palominos

"The mining industry is currently facing significant challenges to identify and adopt sustainable collector chemistry that effectively recover value minerals in difficult-to-process low-grade resources. These are typically characterized by complex mineralogy and the presence of significant amounts of penalty gangue sulfide minerals, especially pyrit which is a challenge to separate from value minerals at many major mine operations. Three chemical strategies for dealing with gangue sulfides and penalty elements are: a) selective flotation of value minerals while rejecting penalty minerals in the whole circuit, b) rejecting penalty minerals in an appropriate part of the circuit using selective depressants, c) using a combination of selective collectors and depressants in appropriate parts of the circuit. This paper will evaluate different strategies for dealing with those penalty elements and propose the most efficient alternative. New products and application technologies have been developed in the past 25 years by Cytec for implementing these strategies as dictated by the particular needs of a given plant. However, in recognition of the growing interest in meeting the sustainability challenges, Cytec Research and Development have been focused in the development of greener products (collectors, modifiers and frothers) and processes using FLOTATION MATRIX 100TM approach used to develop the optimal collector system for each specific ore. An overview of these new developments is given in this paper using case studies of application of selective collectors and polymeric modifiers including the newer, greener chemistries."

Jan 1, 2014

By Yuhua Wang, Haitao Zheng, Guangli Zhu, Yuehao Zhao, Fushun Yu, Dongfang Lu

"Spodumene, feldspar and quartz possess similar surface properties, which make the difficult to separate spodumene from other silicate minerals by flotation. The differences of crystal structure, surface property and floatability of three minerals were studied by various technical means. The results show that Li-O and Al-O bonds in spodumene structure are not strong and easy to be broken. However, Al-O and Si-O bonds in feldspar and Si-O bond in quartz are very strong and not easy to be broken. High contents of Al and Li on spodumene surface were found by XPS measurements, which is benefit for the adsorption of anionic collector. The surface energies of main cleavage planes of spodumene (110), feldspar (001) and quartz (001) are 1.88 J/m2, 2.97J/m2 and 2.68J/m2, respectively. Hence, the exposed surfaces of feldspar and quartz are not saturated and easy to adsorb OH- ions from solution and cause the lower IEP than spodumene. The contact angles of three minerals in water are lower than 16º, suggesting that the hydrophilicity of three minerals is high, and the order of hydrophilicity is quartz > feldspar >spodumene. Correspondingly, contact angles and flotation recoveries of spodumene are bigger than that of feldspar and quartz in presence of a combined anionic and cationic collector named YOA.INTRODUCTION Flotation technology plays most important role for the recovery of spodumene from pegmatite ore. Generally, spodumene with fresh surface is easy to be floated using soap and oleic acid as collector, and the best flotation pH range is 4.0 to 9.0. However, the flotability of spodumene will become worse when its surface was polluted by slime which produced by the weathering of spodumene and other silicates (Dresler et al. 1998; Moon and Fuerstenau 2003; Menéndez et al. 2004; Yu et al. 2015). In addition, the species of Ca2+, Fe3+, Mg2+ and other metal ions in pulp can not only activate the flotation of spodumene, but also the activation of gangue minerals, and then the flotation selectivity of spodumene from gangue minerals became wores (Wang and Yu 2007; Yu et al. 2014). In order to eliminate the negative effects of slime and metal ions on the flotation of spoddumene, the desliming and long time scrubbing with the addition of NaOH and Na2CO3 were adopted. Usually, NaOH shows the activation for spodumene flotation, and the recovery of spodumene increases with the increase of NaOH dosage. Na2CO3 can eliminate the non selective activation of Ca2+, Fe3+, Mg2+ ions in the pulp, and the concentrate grade of spodumene increases with the increase of Na2CO3 dosage. Anionic collectors such as chelants, hydroxamic acid, oxidized paraffin soap, naphthenic acid and oleic acid were widely used for the flotation of spodumene (Dresler et al. 1998; Moon and Fuerstenau 2003; Menéndez et al. 2004; Yu et al. 2015)."

Jan 1, 2018

By Bharat Garg

The coking coal or clean coal from raw material division, Tata Steel Ltd. is a prime source of energy for inhouse steel making. Coal reserves of semi soft coking coal at West Bokaro is beneficiated by dense media cyclone and froth flotation processes to produce clean coal. In dense media cyclone process two byproducts-middling and rejects are also produced along with clean coal. With the growing demand for clean coal, it becomes imperative to maximize the recovery of clean coal in beneficiation processes. This will help, not only in reduction in cost of production, but also in raw resource conservation, and proper utilization. In this context, a case study was conducted at West Bokaro to identify opportunities for clean coal recovery from by-products. This paper mainly discusses the process for recovery of clean coal from byproducts and study of further liberation of clean coal from byproducts for economic consideration.

Sep 1, 2012

By Nidhi Kumari

This work is based on surface chemical properties of bacteria during adaptation to high grade copper minerals and the projected consequences in Bio-Flotation process. The utility of bio-processing in the beneficiation of copper ore through bio-flotation is demonstrated. An autotroph Acidithiobacillus Ferrooxidans bacterium is adapted to high grade mixed copper ore sample by repeated subcultures. The surface characteristics were studies by analyses at different pH and time intervals. From the studies, it was established that the mineral-adapted cells became more hydrophobic as compared to unadapted cells during bio-flotation. It was also noticed that there was no significant changes in the surface charge of bacteria before and after adaptation. Keywords: bio-flotation, copper, Acidithiobacillus ferrooxidans, hydrophobic

Sep 1, 2012

By C. L. Tang

Parts of the wastewater are reused directly and the rest moderately purified and reused, so the utilization rate of wastewater of the whole processing plant reaches 100 percent. At the same time, beneficiation indicators have been improved stably, and great economic and social benefits have been achieved.

Jan 1, 2014

By Sydney Mantsho, Toni Streczynski, Manuel Gonzalez

"In 2013, the commissioning of the MillStar Stabilisation and FloatStar Stabilisation and Optimisation controllers were completed at the Cerro Bayo Silver (Ag) mine in Patagonia, Chile. The MillStar control system has stabilised the feed to the SAG mill as well as the density at the discharge end of the SAG mill and ball mill. The FloatStar Stabilisation and Optimisation controllers have successfully stabilised and optimised the flotation circuit to ensure consistent product quality within desired specifications.The mill feed is controlled utilising the MillStar Solids Feed controller. Additionally, the solids to liquid ratio into the SAG mill was controlled utilising the Mill Inlet Ratio controller in conjunction with the Solids Feed controller. The discharge end of the milling process is a highly interactive and complex system. The use of a Robust Nonlinear Model Predicative Controller (RNMPC) was ideally suited to control this section of the process. On the Cerro Bayo milling circuit, the RNMPC was used to control the mill discharge sump level and the primary cyclone feed density to produce a more consistent feed to the flotation circuit.Three levels of the FloatStar control system were installed, for flotation stability, concentrate flow stability as well as grade optimisation. The Level Stabiliser was used to stabilise the level control on 6 flotation banks. The Flow Optimiser was commissioned on the Rougher, Scavenger and Cleaner concentrate sumps to stabilise concentrate flow from the flotation cells. The Grade Recovery Optimiser was commissioned on the Roughers section. A number of instrumentation challenges were identified which limited the overall benefit derived from the system. Once these were addressed, the performance was optimised. The overall benefit provided by the system was observed in terms of the improvements in Ag recovery."

Jan 1, 2014

By K. Saberyan

In this study, solvent extraction of zirconium by using triphenylphosphine oxide as extractant has been investigated. The results showed that extraction of zirconium by triphenylphosphine oxides in nitric acid and hydrochloric acid media were negligible. Extraction of zirconium in acetic acid media with concentration of 0.01~0.2 M has been studied and the results showed that the maximum percent of zirconium extraction was 40% in acid acetic with concentration of 0.01 M. By addition complexing agents such as potassium thiocyanate with the concentration of 0.01~0.2 M zirconium extraction increased up to 86% in 0.2 M potassium thiocyanate. By addition of sodium salicylate with concentration of 0.01 M and in pH=2.5, the maximum extraction of 96% was achieved. The striping of zirconium from organic phase can be carried out by 0.5 M solution of sulfuric acid.

Jan 1, 2014

By Auhin Kumar Maparu

Metal oxide nano-particles are used as additives in various industrial applications such as pigments in paints, additives in adhesives, plastics, cosmetics, functional coatings, personal care and health care products, for antibacterial applications and more recently in heat transfer applications. In most of these applications, usually dry nano-particle powders are added to the formulations. However, often it becomes difficult to achieve a uniform and stable dispersion of nano-particles in the given formulation. Thus, a scalable and commercially viable process for in-situ production of stable nano-particles suspensions in the desired medium will certainly be more beneficial. Ultra-fine grinding in high energy mills (planetary mill, stirred media mill) has been used to produce fine particles (sub-micron size). However, in order to obtain nano-particles (particle size <100 nm), the choice of appropriate dispersant and solvent is crucial, since freshly generated nano-particles tend to agglomerate due to their high surface reactivity. We have employed molecular modeling (MM) based selection methodology to arrive at the most suitable solvent?dispersant combination for preparation of the given metal oxide nano-particles. Molecular modeling techniques are employed to compute the interaction energy of a given dispersant with surface of the metal oxide particles in the presence of the dispersion medium. The interaction energy helps identify a dispersant that has strong affinity for the metal oxide surfaces allowing for strong dispersant adsorption and hence a more stable dispersion. For example, in case of aqueous nano-titania suspensions, poly-carboxylic acids like citric acid provide better dispersion than mono-carboxylic acids like lauric acid, mysristic acid, and oleic acid. While in non-aqueous medium like ethanol, p-hydroxybenzoic acid and glycerol trioleate perform better. The suspension is produced in-situ by ultra-fine grinding of the metal oxide powder in the presence of the selected dispersant and dispersion medium in a planetary ball mill. By careful selection of various process parameters such as percent loading of powder, jar filling, grinding media to powder ratio, time and amount of dispersant addition, both aqueous and non-aqueous suspensions of metal oxide nano-particles with average particle size less than 100 nm are produced. The aqueous suspensions of alumina and titania produced in presence of citric acid dispersant exhibit median particle size of 83 and 62 nm, respectively. These suspensions have been found to be stable for nearly 3 years. The nano-particles thus produced are used in the preparation of nano-fluids?advance heat transfer liquids, which show enhanced heat transfer capabilities and unaltered stability and performance even after several heating-cooling cycles. The nano-particles are also utilized for making efficient photo catalysts, which are found to be highly effective under sunlight. Keywords: stability, nano-fluid, milling, grinding, thermal conductivity, nanocoolant, photocatalyst

Sep 1, 2012