Bis(tert-butylamido)cyclodiphosph(III)azanezirconium- and hafnium dichloride are good polyethylene pre-catalysts, but due to the basicity of their phosphorus(III) atoms they suffer from ligand degradation. To lessen the Lewis-acid attacks on these complexes, the phosphorus-nitrogen ligands were ...

In hydrothermal condition hafnium selenite with estimated chemical composition Hf(SeO3)2·n(H2O) was obtained and characterized by powder X-Ray diffraction, IR spectroscopy and thermogravimetrical analysis. The composition of the obtained crystalline phase was established as dihydrate of tetraaq...

In this work, the flotation of pentlandite/lizardite system was studied in deionized water, brine and solutions containing some special “constitution ions” with different ionic strengths, respectively. The flotation results show that the “constitution ions” significantly improve the recovery...

The effect of lizardite surface characteristics on pyrite flotation has been investigated through flotation tests, adsorption tests, zeta potential measurements, FTIR study, X-ray photoelectron spectroscopy (XPS) and sedimentation tests. The flotation results show that at pH value 9, where flota...

The near-equilibrium dissolution kinetics of partially dehydroxylated lizardite was investigated at conditions relevant for ex situ CO2 mineralization, namely 30°C⩽T⩽90°C and pCO2

The solubilization and mobilization of elements from silicate minerals during fungal weathering are predominantly promoted by acidification and complexation reactions. However, stark differences exist in the release rates of different elements driven by fungal-derived low molecular weight organi...

This investigation examines the experimental data obtained from a 30 L pilot batch reactor, used for single stage aqueous carbonation and for the dissolution of heat activated lizardite and compares this data to the laboratory scale data obtained under similar reaction conditions. Two mineral fe...

The present theoretical study analyzes the kinetic characteristics of precipitation of magnesite and lizardite as a result of hydrothermal alteration of olivine under high carbonate alkalinity. It makes use of a simulation strategy in which, both the chemical evolution of the aqueous solution an...

Despite that the negative effects of lizardite on pentlandite flotation have been realized, the lizardite effects under different slurry pH have not been sufficiently investigated. Micro-flotation test results showed that pentlandite recovery gradually decreased with the increase in slurry pH wh...

To reduce the negative effects of lizardite on the flotation of pentlandite, amino trimethylene phosphonic acid(ATMP) was tested as a potential depressant for lizardite. Micro-flotation test results indicated that the flotability of pentlandite restored in pentlandite-lizardite system by the add...

The role of aluminum ions on the flotation of pentlandite depressed by lizardite has been studied by flotation tests, adsorption tests, zeta potential measurements, solution chemistry calculation and particle size distribution test. The results show that the finer the lizardite slime is, the low...

To remove lizardite slimes from pyrite surface in pyrite-lizardite system, 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) was introduced as a possible depressant for lizardite slimes. Micro-flotation test results showed that PBTCA can remove lizardite slimes from pyrite surface and the float...

A critical study has been made of the effect of acid concentration and of polymerized and depolymerized zirconyl ions on the formation of ZrO-XO complexes and their stabilities. At an optimum acidity of 0.5–0.6M hydrochloric acid, most of the common cations occurring in silicates do not interfe...

Carboxymethyl cellulose sodium (CMC) was used as the template to prepare zirconium hydroxide nanoparticles. The resulted Zr-CMC was composed of about 29.4 wt% CMC and amorphous zirconium hydroxide. Zirconium hydroxide nanoparticles in size of 20–50 nm were encapsulated by CMC, which could impro...

This work first synthesized sol of the precursor of zirconium oxide by reacting zirconyl chloride octahydrate (ZrOCl2 · 8H2O) with nitrilotriacetic acid (NTA) in ammonia solution. NTA (R(COO−)n), acts as the complex compound, reacts with ammonium hydroxide to produce an ionized complex agent R(...

In situ and ex situ X-ray diffraction, and transmission electron microscopy were used to investigate the calcination of four samples of zirconia manufactured using two different zirconia reactant solution concentrations (0.81 M and 1.62 M) with precipitation carried out at pH 3 and 12. The calci...

The catalysts prepared from zirconyl chloride and sodium pyrophosphate exhibited high activity and selectivity for the oxidative coupling of methane. We suggest that the catalytically active substances are most likely to be NaCl-promoted sodium zirconium phosphates and NaCl plays a key role in a...

The effect of pH of precipitation, starting solution concentration, and agitation levels on the particle size of hydrous zirconia precipitates have been investigated. It was found that all three variables affect the particle size of the hydrous zirconia. The smallest particle size is produced by...

A simple preconcentration method for zirconium based on coprecipitation with aluminium hydroxide prior to flame atomic absorption (FAAS) determination was established. The recovery values of the analyte ions were higher than 95%. Such parameters as the type of hydroxide ion source for precipitat...

Two ion-exchangers, the first is organic in nature and the other is inorganic named as resorcinol–formaldehyde (R–F) and zirconyl-molybdopyrophosphate (ZMPP) were synthesized and applied to decontaminate some fission radionuclides from radioactive waste streams. The distribution coefficients o...