BIOLEACHING LITHIUM NICKEL MANGANESE COBALT OXIDE (NMC) BATTERY WASTE USING BACILLUS ARYABHATTAI STRAIN SKC-5 AND PSEUDOMONAS PLECOGLOSSICIDA STRAIN SKC/SH-9 WITH VARIATION OF MEDIUM COMPOSITION

• Main Author: Satriadi, Teguh
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/87896
• Institution: Institut Teknologi Bandung

The growing utilisation of electric vehicles triggers an increase in lithium-ion battery (LIB) waste. One of the most widely used types of LIBs is nickel manganese cobalt oxide (NMC). This type contains valuable metals, namely Li, Mn, Ni, and Co, which are highly required in various industrial sectors. These valuable metals can be recycled to reduce environmental impact and fulfil the growing demand for metals. Bioleaching as an alternative recycling method offers the potential to address the environmental and economic issues associated with environmentally friendly waste batteries. This study aims to optimise the bioleaching process of black mass LIBs using Bacillus aryabhattai strain SKC-5 and Pseudomonas plecoglossicida strain SKC/SH-9 bacteria. This study aims to evaluate the potential of Bacillus aryabhattai strain SKC-5 and Pseudomonas plecoglossicida strain SKC/SH-9 bacteria in the bioleaching process of used NMC batteries by varying the medium composition. A series of bioleaching experiments were conducted to study the effect of bioleaching medium on the percent extraction of Li, Ni, Co, Mn, and Cu metals. The bioleaching process was conducted at room temperature (±25 °C), with a medium pH of 1.15–1.2, a black mass particle size fraction of -200# (-75 ?m), 10% (v/v) bacterial inoculum, and a rotary shaker speed of 180 rpm for 10 days. Bioleaching experiments were conducted at 5% pulp density with three medium variations as follows: 2.8 g/L pyrite, 1.3 g/L sulphur, and 2.8 g/L pyrite and 1.3 g/L sulphur. Percent metal extraction as a function of time at various bioleaching conditions was periodically determined from the data by analysing dissolved metal concentrations with ICP-MS (Inductively Coupled Plasma-Mass Spectrometry). Based on the experimental results, the best bioleaching process parameter of Bacteria Bacillus aryabhattai strain SKC-5 is a medium variation of 2.8 g/L pyrite with a metal extraction percentage value of 85.74% Li, 44.45% Ni, 50.67% Co, 56.59% Mn, and 85.65% Cu. Bacteria Pseudomonas plecoglossicida strain SKC/SH-9 is the medium variation of 2.8 g/L pyrite with a metal extraction percentage value of 98.69% Li, 43.29% Ni, 49.40% Co, 52.45% Mn, and 92.48% Cu. The use of pyrite (FeS?) in the bioleaching process provides significant advantages by continuously supplying iron ions (Fe²?), which act as reducing agents throughout the process. The oxidation of pyrite also generates various sulfur compounds, such as sulfate ions (SO?²?) and complex sulfur compounds, which can function as complexing agents. Additionally, pyrite plays a role in enhancing the redox potential of the bioleaching system through the redox cycle between Fe²? and Fe³?.