Diethylenetriamine as a selective pyrrhotite depressant: Properties, application, and mitigation strategies

Abstract

Pyrrhotite (Po) is an abundant iron sulphide mineral that occurs in nickel sulphide deposits, such as those in Sudbury, Ontario. Due to its low economic value and its high contribution to SO2 emissions produced during smelting, Po is rejected into the tailings during mineral processing. The rejection of Po can be accomplished in several ways, including by using chelating agents such as diethylenetriamine (DETA) as depressants in froth flotation. DETA can significantly improve nickel recovery and concentrate grades; however, it is challenging to manage in the tailings area. DETA, when used, forms stable chelates with Ni2+ and Cu2+ which cannot be precipitated with traditional lime treatment. Once in the tailings management area, DETA can desorb from Po solids upon dilution or with changes in temperature and/or pH. The species chelated with DETA can also change depending on the availability of the ions in solution. The use of DETA can, therefore, lead to concentrations of Ni2+ and Cu2+ in final effluent that exceed the regulated amounts. Due to the challenges with chelated metals in effluent, it is recommended that the chelating agents be removed from the tailings stream before it is deposited. Although DETA‐metal chelates are rarely discussed in the literature, some mitigation and degradation strategies investigated by industry are discussed in this review. DETA degradation methods are also discussed, with the primary focus being on biodegradation. DETA has generally been described as recalcitrant to biodegradation although there is evidence that proper acclimation should allow bacteria to develop DETA degradation pathways.

Experimental methods in chemical engineering: pH

“…has published 129 articles that mention pH as a keyword. The topics include diethylenetriamine as a selective pyrrhotite depressant, [ 64 ] pitting mechanisms of Zn‐Ni alloy coating, [ 65 ] and water/oil emulsion stability. [ 66 ] To better identify relationships between diverse areas of research like these, we applied the program VOSViewer to generate a bibliometric map of the 100 most frequently cited keywords (Figure 4).…”

Isotherm and Kinetic Study of Metal Ions Sorption on Mustard Waste Biomass Functionalized with Polymeric Thiocarbamate

“…Due to its high solubility in water and the large number of functional groups with N and S donor atoms, this organic reagent allows the quantitative removal (>99.5%) of a large number of metal ions (Cu(II), Zn(II), Ni(II), Pb(II), Hg(II), etc.) [ 28 ]. However, the use of METASORB in the treatment of industrial effluents by precipitation has two major disadvantages, namely (i) the excess of the organic reagent added for precipitation (which does not react with metal ions) leads to the contamination of the effluents with organic compounds, and therefore, to an increase in the value of chemical oxygen demand (COD, mg O 2 /L); and (ii) the recovery of metal ions from the precipitate is difficult (due to the high stability of the chelated complexes), which is why the sludge obtained after the removal of metal ions is stored for destruction.…”

Dissolution behaviour of different rank coals in L‐glutamic acid N, N‐diacetic acid chelating agent: Implications to enhance coalbed methane recovery by acid stimulation

“…Chelating agents have been widely used in processing technology, the textile industry, contaminated soil remediation, and other applications. [ 19–21 ] In the field of coal mining, chelating agents were used to recover rare earth elements (REE) from coal fly ashes [ 22 ] and inhibit the spontaneous combustion of coal by reducing the catalytic effect of metal ions. [ 23 ] In the oil and gas industry, the applications of chelating agents include scale removal and inhibition, wettability alteration, filter cake removal, enhanced oil recovery (EOR), and hydraulic fracturing treatments.…”