Intensifying Acid Leaching Behaviors of Fe, Ni, and Cr from Stainless-Steel Scraps via Ultrasonic Treatment

Stainless steel has a broad application in various areas of the national economy, while a mass of stainless-steel scraps is generated during the abrasive machining process. These scraps are rich in metallic ingredients such as Fe, Ni, and Cr, which shows an extremely comprehensive recovery value. Due to good plasticity and ductility, the stainless-steel scrapsStainless-steel scraps are hard to grind to fine particlesParticle. The low dissolution efficiency of coarse particlesParticle limits the efficient utilization of stainless-steel scrapsStainless-steel scraps. This work provides a clean and intensifyingIntensifying acid leachingAcid leaching method of Fe, Ni, and Cr from stainless-steel scrapsStainless-steel scraps via ultrasonic treatment. Under the conditions of ultrasound power of 540W, H2SO4 concentration of 3 mol/L, leachingLeaching time of 15 min, temperature of 30 °C, and liquid-to-solid ratio of 20:1, the leachingLeaching efficiencies of Fe, Ni, and Cr are 99.93, 99.91, and 99.92%, which are much higher than those with the conventional leachingLeaching process.