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Resources and Sustainable Materials
Published in Stanley E. Manahan, Environmental Chemistry, 2022
Zinc is moderately abundant and not particularly toxic, so its industrial ecology is of less concern than that of toxic lead or scarce chromium. As with other metals, the mining and processing of zinc can pose some environmental concerns. Zinc occurs as ZnS (a mineral called sphalerite), and the sulfur must be reclaimed as SO2 in the smelting of zinc. Zinc minerals often contain significant fractions of lead and copper, as well as appreciable amounts of toxic arsenic and cadmium. Zinc ore typically containing approximately 6% zinc is concentrated by a flotation process in which air is bubbled into a slurry of finely ground zinc ore in water treated with special chemicals, and a froth concentrate of zinc sulfide containing up to 50% zinc is skimmed off the top. Up to 90% of the zinc in the ore is recovered.
Recycling of Wastes Generated in Automobile Metal–Air Batteries
Published in Ram K. Gupta, Tuan Anh Nguyen, Energy from Waste, 2022
Weng Cheong Tan, Lip Huat Saw, Ming Chian Yew, Ming Kun Yew
During the electrochemical reaction, zinc metal is consumed to form zinc oxide as a by-product. The recycling of zinc can be conducted in two ways: hydrometallurgical process and pyrometallurgical process [9,10]. However, hydrometallurgical processes are more popular than pyrometallurgical processes and contribute to about 90% of zinc produced globally. Zinc–air batteries are widely used in miniature hearing aids. This is because they possess a high specific density with low cost. Panasonic, Power One, and Duracell are some of the companies that offer zinc–air button batteries in the market.
Bioremediation: Plants and Microbes for Restoration of Heavy Metal Contaminated Soils
Published in Jos T. Puthur, Om Parkash Dhankher, Bioenergy Crops, 2022
Harsh Kumar, Shumailah Ishtiyaq, Mayank Varun, Paulo J.C. Favas, Clement O. Ogunkunle, Manoj S. Paul
Zinc (Zn) is an element with an atomic number of 30. Zn is an essential metal that belongs to Group II of the Periodic Table and occupied the 24th position among elements that are abundant in the Earth’s crust. Zinc is a transition metal that typically exists in nature in its divalent state (+2). It is known as one of the most essential minerals for living organisms. However, significantly increased concentration of Ni is toxic (Hambidge and Krebs 2007). Zn plays an important function in plants, the most relevant is its activity as a functional activator of a variety of enzymes (peptidases, dehydrogenases, phosphohydrolases, and proteinases) (Clarkson and Hanson 1980). Maximum Zn in the natural soil is 10-300 ppm (Tisdale et al. 1985). The clay contains three times more Zn than sandy soil. The major areas of Zn mining are Russia, Australia, the USA, Canada, and Peru. Global supply crosses seven million tonnes per year, and commercially exploitable reserves reach a hundred million tons.
Competent inhibitor for the corrosion of zinc in hydrochloric acid based on 2,6-bis-[1-(2-phenylhydrazono)ethyl]pyridine
Published in Chemical Engineering Communications, 2019
M. Abdallah, S. A. Ahmed, H. M. Altass, I. A. Zaafarany, M. Salem, A. I. Aly, E. M. Hussein
Zinc metal is used in many industrial applications such as the manufacture defensive coatings for steel, vehicle, shipbuilding industries, household electrical appliances, batteries and other light industries. HCl solutions are used for pickling and cleaning zinc surfaces, which are highly susceptible to corrosion when exposed to acid solutions, especially HCl. Corrosion inhibitors are used to reduce the aggressive attack of acid (Agrawel et al., 2004). The most common corrosion inhibitors are nitrogen-, oxygen-, and/or sulfur-based organic compounds. These compounds inhibit zinc corrosion in the acidic medium by absorption on the zinc surface (Troquet et al., 1981; Abdallah, 2003; Wang et al., 2003; El-Sherbini et al., 2005; Abdallah et al., 2009b; Abiola and James, 2010; Fouda et al., 2006, 2010; Shanbhag et al., 2011; Abdallah et al., 2011, 2012a, 2013b, 2014, 2016b; Suedile et al., 2014).
Innovative Recovery of Gallium and Zinc from Corundum Flue Dust by Ultrasound-Assisted H2SO4 Leaching
Published in Mineral Processing and Extractive Metallurgy Review, 2023
Wei Ding, Shenxu Bao, Yimin Zhang, Bo Chen, Xueli Wan, Junhui Xiao
Zinc is one of the important endangered metals which is a crucial element for different industrial sectors and any form of life on Earth. About 70% of the world’s zinc comes from primary (natural resources) and only 30% from secondary resources. Zinc can be produced and recovered from secondary resources such as industrial fumes, spent batteries, tailings, etc (Zhai et al. 2022a). The primary way to recover zinc from electric furnace dust is hydrometallurgy. According to the different leaching agents, it can be divided into acid leaching, alkali leaching and ammonia leaching (Hu et al. 2021). Zinc oxide can be dissolved in acid into the leachate, and metal zinc ingots can be obtained by purification and electrowinning treatment of the leachate.
A Novel Technology for the Recovery of Zinc from the Zinc Leaching Residue by the Bottom-blown Reduction
Published in Mineral Processing and Extractive Metallurgy Review, 2021
Zhongtang Zhang, Weifeng Li, Jing Zhan, Gui Li, Zhenbo Zhao, Jian-Yang Hwang
Zinc is an important metal resource for industrial development, widely applied in electroplating, metallurgy, storage batteries, brass and automobile manufacturing (Jha, Kumar and Singh 2001). Most zinc is extracted from zinc sulfide concentrate through the roast-leach-electrowinning process (Balarini, Polli and Miranda 2008; Çopur, Özmetin and Özmetin 2004; Han, Liu and Qin 2015; Liu, Li and Xie 2020). On one hand, a large amount of zinc leaching residue is produced, which should be reasonably handled owing to the presence of various toxic metals during leaching (Behnajady and Moghaddam 2017; Rüşen and Topçu 2018; Turan, Altundoğan and Tümen 2004). On the other hand, zinc leaching residue is also the main material for secondary zinc recovery.