Extraction of Copper Using Chicken Dung and Concentration of Titanium Using Biomass from Ores in Maragwa Location, Tharaka Nithi County

Abstract

Mineral data shows several deposits of copper and titanium minerals in Kenya yet the country continues to import copper and titanium products. In some regions of Tharaka Nithi County, occurs ores that are known to contain both copper and titanium minerals. These minerals have never been earmarked for extraction mainly because the common methods known for extraction are expensive. In addition, the hydrometallurgical or pyrometallurgical process used in copper extraction releases greenhouse gases into the environment. Titanium minerals, on the other hand, are relatively found free of iron minerals. However, titanium extraction from ores must be found mixed with iron minerals. The objective of this study was to extract copper from the ores using impure hydrazones derived from chicken dung and concentrating titanium using ore-laterite-carbonized biomass, carbonized biomass, and froth floatation. Samples were obtained from the selected ore deposits of Maragwa location in Tharaka Nithi County. The samples were obtained at 30 cm depth (level A) and further one-meter depth (level B). Samples obtained were dried at 105oC for 9 hours and later ground to 60.0 meshes (250 microns) using a ball mill. Copper minerals were leached using hydrochloric acid. Titanium in the ore was concentrated using carbonized biomass, ore-laterite-carbonized biomass at 800-900°C, and froth floatation method. The analyses of the minerals for the mineralogical and chemical composition were done using X-ray Diffraction Spectroscopy (XRD), X-ray Fluorescence Spectroscopy (XRF) and Atomic Absorption Spectroscopy (AAS). The chicken dung was characterized using FTIR and MS methods. The copper mineral obtained was chalcopyrite. Copper composition was found to be 4.46%, with a mean of 4.47±0.70% at level A and 4.44±0.60% at level B. The mean rutile composition was found to be 0.92±0.11% with a mean of 0.77±0.16% at level A and 0.86±0.17% at level B. After concentration, rutile improved with a range of 1.0 to 2.5%. Reduction of copper using chlorinated chicken dung at pH above 11 produced copper with purity ranging from 57-85%. The use of iron electrode in acidic media during copper extraction produced Cu with purity ranging from 51-78%. It was found that the aluminium electrode was suitable for monitoring the reduction process of copper from the mixture of ore leachate and chlorinated chicken dung leachate. The copper composition in all deposits was found to be above the cut-off grade of 0.4 to 1.0 percent which is mined in other countries. The reduction of copper using chicken dung generated hydrazones was found to be a good method of copper extraction. This method of copper extraction does not require heavy capital investment since the chicken dung is locally available. The concentration of the ore - laterite using carbonized biomass was also found to be the best method of concentrating titanium from ores. The method is viable because laterite soils (heavily weathered material which is rich in iron oxides or alumina or both) are widely available while biomass is obtained from municipal waste. The experiments were done on the laboratory scale. The study, therefore, recommends a pilot study on large scale copper extraction and titanium concentration using the optimized values.