# Surface Modification of Organic Chromium-Free Tanned Leather Shavings and the Immobilization of Lipase

## TL;DR

This paper presents a method to reuse leather scraps by immobilizing an enzyme to break down waste oil, promoting sustainable leather production.

## Contribution

A chromium-free leather waste-based system for enzyme immobilization with enhanced performance and environmental compatibility is introduced.

## Key findings

- Immobilized pancreatic lipase showed improved catalytic activity and stability compared to free enzyme.
- The system demonstrated good environmental compatibility after degradation.
- The method uses leather-making waste and mild conditions, supporting clean production.

## Abstract

Following the concept of “waste into resources”, a mild and controllable light grafting technique was used to immobilize pancreatic lipase (PPL) in situ on modified organic, chromium-free tanned leather scraps to catalyze the hydrolysis of waste oil. The experimental results showed that immobilized PPL significantly improved the catalytic activity, operational stability, reusability, and storage stability compared to free PPL. Furthermore, the study evaluated the environmental compatibility of the system through biological risk assessment of soil extracts after degradation, indicating that the system has good environmental compatibility. The experiment is simple to operate, uses mild conditions, and the immobilized material is obtained from leather-making solid waste. The use of this immobilization system to treat waste oil in the leather-making process is of great significance for achieving clean and sustainable production in the leather industry.