Recycling nickel from spent catalyst of Phu My fertilizer plant as a precursor for exhaust gas treatment catalysts preparation

• Published in: Journal of material cycles and waste management Vol. 19; no. 3; pp. 1085 - 1092
• Main Authors: Le-Phuc, Nguyen, Luong, Thuy Ngoc, Van Tran, Tri, Pham, Yen Thi Hai, Ngo, Phuong Thuy, Nguyen, Sura
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Japan 01.07.2017; Springer Nature B.V
• Subjects: Aluminum; Aluminum oxide; Catalysts; Chemical synthesis; Civil Engineering; Cobalt; Engineering; Environmental Management; Exhaust gases; Feasibility; Fertilizers; Hazardous wastes; Heavy metals; Leachates; Leaching; Manganese; Nickel; Nitrates; Oxidation; Phase transitions; Precursors; Purity; Recovering; Recycling; Reduction (metal working); Regulations; Special Feature: Original Article; Studies; Transition metals; Waste Management/Waste Technology; NO; Fertilizer plant; Spent catalyst; CO-HC oxidation; reduction; Leaching
• ISSN: 1438-4957; 1611-8227
• DOI: 10.1007/s10163-017-0609-1

In this study, a very promising way of treating and recycling spent nickel catalysts of fertilizer plants in Vietnam was proposed. Firstly, nickel was recovered from spent catalyst using HNO 3 —leaching process. Results show that nickel recovery of over 90% with a purity of over 90% can be achieved with HNO 3 2.1–2.5 M at 100 °C in 75 min. The residue after leaching is not considered as a hazardous waste according to the Vietnamese regulations. Then, the leachate solution was used as a precursor to prepare a model catalyst for exhaust gas (CO, HC, NO x ) treatment. In comparison with the catalyst prepared from the commercial nickel nitrate solution, the catalyst synthesized from recovered nickel exhibits similar properties and activities. The influence of Ni loading of Ni/alumina catalyst as well as the modification of active phase by some metals addition (Mn, Ba, Ce) was also investigated. It is feasible to modify active phase by transition metals such as Mn, Ba, and Ce for complete oxidation of CO and HC at 270 °C and a reduction of NO x below 350 °C at high volumetric flow condition (GHSV = 110.000 h −1 ).