Iqbal Zafar

Beneficiation of low grade carbonate-rich phosphate rocks using dilute acetic acid solution

The carbonate-rich phosphate rocks have no direct use and are rejected all over the world. Substantial amounts of low-grade phosphorites are found along with high grade ore in some areas of Hazara (Pakistan). In the technique described dilute acetic acid solution has been used for leaching of the carbonates contained in Hazara low-grade, carbonate-rich phosphate rocks. In this work, the effect of acetic acid concentration, reaction time and liquid/solid ratio (vol/wt. basis) have been studied. It was found that upon treatment of the ground ore with acetic acid, the tricalcium phosphate (TCP) percent can be raised by up to 23% corresponding to a reduction of up to 62% in the calcium carbonate content of the samples, depending on the conditions of the reaction as well as the nature and size of the raw phosphate particles used for analysis.

Beneficiation of zinc from electric arc furnace dust using hydrometallurgical approach

Zinc bearing wastes such as electric arc furnace dust (EAFD) obtained from steel making constitute an important resource for zinc extraction. Inclusion of heavy metals such as Pb, Cd, Cu, Cr, Ni, etc., in these wastes makes them hazardous to use and/or dispose. In the present research work, leaching kinetics of EAFD with sulfuric acid has been investigated and various experimental parameters such as concentration of lixiviant, stirring rate, sample particle size, liquid/solid proportion, and temperature of the reaction have been optimized. It has been found that the dissolution rate of EAFD increases with rise in temperature, acidic strength, rate of stirring, liquid to solid proportion and with reduction in EAFD particle size. From the analysis of leaching kinetic data by means of graphical and statistical methods, it has been evaluated that the leaching kinetics of EAFD is dictated by surface diffusion reaction. Apparent energy of activation for the leaching reaction of EAFD with sulfuric acid is found to be 13.1 kJ mol–1 within the temperature range of 308 to 358 K.

Development of new multifunctional terpolymer sorbent for proteomics applications

Determination of the availability of phases for specific separations is an important task achieved by a separation chemist. This becomes vital when the complex samples like biofluids are dealt with in proteome science. The work presented here involves the synthesis and application of terpolymeric sorbent with different functionalizations adopted for the selective enrichment of biomolecules of interest from biological fluids. Synthesis of terpolymer was carried out by the radical polymerization of monomers: methyl acrylate, acrylic acid and vinyl acetate with diethylene glycol dimethacrylate as cross-linking agent, benzoyl peroxide as initiator and chloroform as a porogenic solvent. Characterization was done through Fourier transform infrared spectroscopy, scanning electron microscopy and nitrogen adsorption porosimetry. The polymer was further modified to immobilized metal ion affinity chromatographic material, with immobilized Fe(3+)/La(3+) ions that allowed phosphopeptide enrichment from tryptic digests of standard proteins as well as milk, egg yolk and human serum. Sensitivity of enrichment down to 50 fmol was achieved in the presence of complex protein background as bovine serum albumin. Hydrophobicity was introduced through octadecyl amine, which provides comparable results to ZipTip C18/C4 for desalting of complex mixtures of all caseins. Analysis of the enriched content was performed by Matrix Assisted Laser Desorption Ionization Mass Spectrometry (MALDI-MS).