Preparation, Characterization and Evaluation of Extraction Effeciency of N-p-tolyl-N benzohydroxamic Acid towards Certain Metal Ions

The hydroxamic acid was prepared by the partial reduction of p- nitro toluene to give N-p-tolyl hydroxyl amine which was coupled with benzoyl chloride to give N-p-tolyl-N-benzohydroxamic acid.The hydroxamic acid prepared was identified by their characteristic colored reaction with vanadium (V) and iron (lll), melting point, I.R. spectra, 1H NMR and mass spectrometry.The extractive properties of hydroxamic acids towards the metal ions like Fe (lll), Cu (ll), Ni (ll) and Co (ll) were examined using appropriate organic solvent. N-p- tolyl -N-benzohydroxamic acid was found to have a maximum extraction for Fe (lll) 75.10% at pH 5.0, Cu (ll) 99.81% at pH 5.0, Ni (ll) 59.45% at pH 7.0 and Co (ll) 99.40% at pH 10.0.The hydroxamic acid was found to extract efficiently metals like Ni (ll) in neutral pH values, Fe (lll), Cu (ll), in pH near to neutral and Co (ll) at alkali pH values.

Flotation Behavior and Synergistic Mechanism of Benzohydroxamic Acid and Sodium Butyl-Xanthate as Combined Collectors for Malachite Beneficiation

Sulfuration flotation is the most widely used technology in malachite beneficiation. However, the inhomogeneity of malachite surfaces usually results in a non-uniform sulfuration surface. The motivation of this work is attempt to adopt different functional combination collectors to enhance the sulfuration flotation of malachite. Accordingly, the flotation behaviors and adsorption mechanisms of benzohydroxamic acid (BHA) and sodium butyl-xanthate (SBX) on the surface of malachite were systematically investigated using flotation tests, zeta-potential measurements, Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, and first-principle calculations. The test results of vulcanization flotation showed that the combined collectors of SBX with BHA possessed a higher recovery than only using SBH by 20%, indicating that there may be a synergistic effect between BHA and SBX. The IR and Raman spectroscopy demonstrated that both BHA and SBX could chemically adsorb onto the malachite surface. The density functional theory (DFT) calculation results further indicated that the combined adsorption energy of BHA and SBX was much lower than that of only BHA or SBX, which confirmed the synergistic effects of BHA and SBX on the malachite surface. This work may shed new light on the design and development of more efficient combined flotation reagents.

Synthesis of 1-(2-Hydroxyphenyl) Dec-2-en-1-One Oxime and Its Flotation and Adsorption Behavior for Malachite

A novel collector of 1-(2-hydroxyphenyl) dec-2-en-1-one oxime (HPDO) was synthesized from 2-hydroxy acetophenone and octanal, and its flotation and adsorption behavior for malachite were studied by flotation tests and x-ray photoelectron spectroscopy (XPS) analysis. The flotation results of a single mineral show HPDO is a special collector for malachite. Compared with benzohydroxamic acid (BHA), isobutyl xanthate (SIBX), and dodecylamine (DA), HPDO exhibits excellent flotation performance for malachite and satisfied selectivity against quartz and calcite over a wide pH range. The HPDO with a concentration of 200 mg/L can float 94% malachite at pH 8, while only recovering 7.8% quartz and 28% calcite. XPS data give clear evidence for the formation of a Cu-oxime complex on malachite surfaces after HPDO adsorption.