Process For Recovery Of Nickel Research Articles

Nickel recovery in tailling from the Chromite beneficiation process in Mau Lam, Thanh Hoa by the reduction roasting-magnetic separation process

In Thanh Hoa province, large chromite ore deposits were discovered. These types of ores also contain significant quantity of nickel metal, with total nickel reserves estimated to be over three million tones. According to the practices of mining and beneficiation of these chromite ores, nickel is discarded in the waste dumps as a non-valuable metal and has not been recovered ever. Through many years of mining and processing of chromite ores, large dumps are formed to such huge volumes that can be considered as a significantly secondary resource of valuable nickel metal. Nickel exists in the form of laterite ores so that it is difficult to be recovered. Currently, there is no commercial technology available for recovery of nickel or other valuable metals from this type of raw material sources. This article presents some research results on applying the reduction calcination – magnetic separation process for recovery of nickel. In particular, some important reduction operating variables such as temperature, calcination time, fuel coal ratio, and Na2SO4 additive were investigated. From the tailing samples of the Mau Lam – Thanh Hoa chromite beneficiation process, important optimal reducing conditions have been determined including 1,1000C of reduction temperature, 8% of anthracite coal, 8% of Na2SO4 additive, and the reduction time of 90 minutes. The reduced product was finely grounded and separated at a magnetic field of 0.3T using the wet magnetic separator. At optimal operating variables, the nickel content of the final nickel concentrate was 4.02% Ni and the overall nickel recovery was 91.2%. The positive results necessarily lead to a need to continue researching the possibility of practical application to recover nickel and thus contribute to the rational utilization of mineral resources of the country.

A novel application of membrane distillation to facilitate nickel recovery from electroplating wastewater.

In many years, the nickel electroplating technique has been applied to coat nickel on other materials for their increased properties. Nickel electroplating has played a vital role in our modern society but also caused considerable environmental concerns due to the mass discharge of its wastewater (i.e. containing nickel and other heavy metals) to the environment. Thus, there is a growing need for treating nickel electroplating wastewater to protect the environment and, in tandem, recover nickel for beneficial use. This study explores a novel application of membrane distillation (MD) for the treatment of nickel electroplating wastewater for a dual purpose: facilitating the nickel recovery and obtaining fresh water. The experimental results demonstrate the technical capability of MD to pre-concentrate nickel in the wastewater (i.e. hence pave the way for subsequent nickel recovery via chemical precipitation or electrodeposition) and extract fresh water. At a low operating feed temperature of 60 °C, the MD process increased the nickel content in the wastewater by more than 100-fold from 0.31 to 33 g/L with only a 20% reduction in the process water flux and obtained pure fresh water. At such high concentration factors, the membrane surface was slightly fouled by inorganic precipitates; however, membrane pore wetting was not evident, confirmed by the purity of the obtained fresh water. The fouled membrane was effectively cleaned using a 3% HCl solution to restore its surface morphology. Finally, the preliminary thermal energy analysis of the combined MD-chemical precipitation/electrodeposition process reveals a considerable reduction in energy consumption of the nickel recovery process.

Investigation on cooperative desulfurization efficiency for bearing carbon stainless steel dust briquettes chromium and nickel recovery process

During the stainless steel making process, Fe-Cr-Ni of lower sulfur content can be recycled from stainless steel dust (SSD) by briquettes reduction. An investigation of cooperative desulfurization efficiency for bearing carbon SSD briquettes reduction process is conducted. First, slag amount prediction model is established through corundum crucible erosion behavior in order to analyze the desulfurization efficiency. Next, the effects of carbon amount, CaF2 amount, silicon ferrous, basicity and feeding modes on the desulfurization rate and the sulfur distribution ratio are analyzed. Furthermore, sulfur distribution ratio prediction model between SSD briquettes and molten iron is originally established in the principle of thermodynamic equilibrium. Results show that basicity, CaF2, silicon ferrous and carbon amount could promote the desulfurization rate and sulfur distribution ratio. When simultaneously adding iron ingot and SSD briquettes, feeding mode has a higher desulfurization rate and better metal/slag separation than when adding iron ingot prior to SSD briquettes. During the experiment, desulfurization rate varies from 55% to 70% and the sulfur distribution ratio results range from 2 to 10. The sulfur distribution ratio prediction results greatly match with experimental results implying that the desulfurization rate analysis method through corundum crucible erosion behavior is more accurate.

Direct recovery of cadmium and nickel from Ni-Cd spent batteries by electroassisted leaching and electrodeposition in a single-cell process

The investigation was aimed at developing a new electrochemical process for recovery of nickel, cobalt and cadmium mainly present in the form of hydroxides in Ni–Cd batteries, in view to obtain, a solid residue composed of metal nickel and carbon, a pure cadmium-free solution of metal salts and metal cadmium. This process relies upon coupling leaching of the metal hydroxides by electrogenerated protons to electrodeposition in a single divided cell. The feasibility of the technique has been first demonstrated in a lab cell operated in batch mode: cadmium-free solution of nickel and cobalt cations could effectively be produced at the end of the 5-h run, with nearly complete leaching of the hydroxides and a current efficiency of the cathode near 73%: occurrence of side hydrogen evolution at the cathode reduced the efficiency during the last hour of the treatment because of insufficient amounts of Cd2+ cations. In a second test, the waste (called black mass) was added at regular intervals, in view to allowing more regular transfer rates of Cd2+ species to the cathode chamber. The more even profiles of concentrations allowed avoiding depletion of this cation, which resulted in higher current efficiency in cadmium deposition. The efficiency of fed-batch mode is finally discussed in relation to the compromise to be found between purity of the cadmium-free solution and current efficiency of cadmium.

Reagent selection for recovery of nickel and cobalt from nitric acid nickel laterite leach solutions by solvent extraction

There is currently no commercial process for recovery of nickel and cobalt from a nitrate-based laterite leach liquor via solvent extraction. Such a process is becoming of interest as nitric acid leaching of nickel laterite ores is progressed by Direct Nickel. Although commercially proven solvent extraction processes do exist for nickel and cobalt extraction from sulphate-based laterite leach liquors, little is known regarding their application to nitrate-based liquors. In the present paper three different solvent extraction systems are compared from a commercialisation standpoint in order to inform future process development. These systems were: neodecanoic acid (Versatic™10)/tributylphosphate (TBP), Versatic 10/pyridine carboxylate (PC), and an aliphatic hydroxyoxime based extractant (LIX®63)/Versatic 10/PC. On the basis of acceptable separation of nickel and cobalt from manganese and magnesium, and ease of metal stripping, the synergistic combination of Versatic 10 and a pyridine carboxylate (in this case nonyl-4-PC) was identified as the most promising system for application to a nitrate-based laterite leach liquor.

Evaluation of a recycling process for printed circuit board by physical separation and heat treatment

Printed circuit boards (PCBs) from discarded personal computer (PC) and hard disk drive were crushed by explosion in water or mechanical comminution in order to disintegrate the attached parts. More parts were stripped from PCB of PC, composed of epoxy resin; than from PCB of household appliance, composed of phenol resin.In an attempt to raise the copper grade of PCB by removing other components, a carbonization treatment was investigated. The crushed PCB without surface-mounted parts was carbonized under a nitrogen atmosphere at 873–1073K. After screening, the char was classified by size into oversized pieces, undersized pieces and powder. The copper foil and glass fiber pieces were liberated and collected in undersized fraction. The copper foil was liberated easily from glass fiber by stamping treatment.As one of the mounted parts, the multi-layered ceramic capacitors (MLCCs), which contain nickel, were carbonized at 873K. The magnetic separation is carried out at a lower magnetic field strength of 0.1T and then at 0.8T. In the +0.5mm size fraction the nickel grade in magnetic product was increased from 0.16% to 6.7% and the nickel recovery is 74%.The other useful mounted parts are tantalum capacitors. The tantalum capacitors were collected from mounted parts. The tantalum-sintered bodies were separated from molded resins by heat treatment at 723–773K in air atmosphere and screening of 0.5mm. Silica was removed and 70% of tantalum grade was obtained after more than 823K heating and separation.Next, the evaluation of Cu recycling in PCB is estimated. Energy consumption of new process increased and the treatment cost becomes 3 times higher comparing the conventional process, while the environmental burden of new process decreased comparing conventional process.The nickel recovery process in fine ground particles increased energy and energy cost comparing those of the conventional process. However, the environmental burden decreased than the conventional one.The process for recovering tantalum used more heat for the treatment and therefore the energy consumption increased by 50%, when comparing with conventional process. However, the market price for tantalum is very large; the profit for tantalum recovery is added. Also the environmental burden decreased by the recycling of tantalum recovery. Therefore, the tantalum recovery is very important step in the PCB recycling. If there is no tantalum, the consumed energy and treatment cost increase in the new process, though the environmental burden decreases.

Sustainable recovery of nickel from spent hydrogenation catalyst: economics, emissions and wastes assessment

Economic viability, carbon emission profile and waste management associated with nickel recovery from spent hydrogenation catalysts are studied from sustainability perspectives. The purpose is to determine and compare the economic, environmental and social implications of different nickel reclamation techniques towards clean, safe and sustainable recovery of nickel from spent catalysts. Sustainability evaluation models are formulated to understand and improve the cost, carbon footprint and resource efficiency of a closed-loop nickel recovery process. The economic viability of the process highly depends on market values of recovered nickel and the production batch size. At a selling price higher than $12.60/kg, an operation with a batch size as small as 50 kg/batch would be profitable. The current rising nickel market, at ∼$18–24/kg, favors recovery operations although it also casts a dual effect on production costs. About 73–82% of carbon emission of the process is from the use of energy in the recovery operation. Energy efficiency is therefore identified as the most critical factor to improve the carbon footprint. The closed-loop process also improves resource use efficiency and minimizes toxic waste generation.

Solvent extraction recovery of nickel from spent electroless nickel plating baths by a mixer-settler extractor

The treatment of spent electroless nickel plating baths has attracted much attention from the standpoints of environmental protection and nickel recycling. In order to design a nickel recovery process from the spent baths, the continuous extraction and stripping of nickel in the spent baths were carried out using a mixer-settler extractor. 2-Hydroxy-5-nonylacetophenone oxime (LIX84I) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A) were used as the extractant and the accelerator, respectively. The effects of the accelerator, flow rates and total stage number were investigated. It was found that the extraction efficiency was significantly increased by adding the accelerator. The extraction and stripping efficiencies were affected by the flow rates of the organic and aqueous phases, and its mechanism was qualitatively discussed on the basis of the stoichiometric relation of the extraction and the hydrodynamic properties of the mixer. A high nickel extraction efficiency (99.9%) was achieved using a countercurrent three-stage extraction process, while the most concentrated nickel sulfate solution (0.49 kmol/m 3) was obtained with the stripping efficiency of 98.4% in a countercurrent two-stage stripping. This continuous extraction–stripping technique is expected to be effective for recycling nickel from the spent baths.

A ferrous chloride-oxygen leach process for nickel-copper sulphide concentrations

This paper describes a ferrous chloride-oxygen leach process for recovery of nickel and copper values from sulphide concentrates available in India. The sulphide concentrates aareleached with a stirred solution of ferrous chloride in a glass-lined reactor operated at various temperatures and oxygen pressures. In this single step process, copper and nickel are converted into their water soluble chloride forms, whereas iron is rejected as hydrated iron oxide with simultaneous generation of sulphur in the non-polluting elemental form. The influence of various parameters such as (i) amount of ferrous chloride (60–100% stoichiometric), (ii) oxygen pressure (0.308–0.515 MPa), (iii) leaching temperature (90–120°C) and (iv) duration of leaching (2–10 h) on the leaching process has been examined. It has been possible to recover 94–99% nickel and 98% copper with low iron contamination by using optinum conditions, such as a stoichiometric amount of ferrous chloride, a temperature of 110°C, an oxygen pressure of 0.377 MPa and a duration of 8 h.