Oxalic acid is a weaker acid than sulfuric acid, which means that it can be used at lower concentrations and milder reaction conditions. This reduces the risk of cellulose degradation and allows for a more controlled and efficient reaction. Further, Oxalic acid is considered to be a more environmentally friendly option compared to sulfuric acid due to its lower toxicity and biodegradability. This makes it a more sustainable choice for nanocellulose extraction, especially in large-scale.