Exploring a new green bleaching path for the paper industry: synergistic application of magnesium hydroxide and hydrogen peroxide

In the papermaking process, bleaching is crucial to improving paper quality. However, traditional bleaching technology is often accompanied by environmental pollution problems. In order to meet this challenge, a new technology using magnesium hydroxide (Mg(OH)₂) and hydrogen peroxide (H₂O₂) as bleaching agents has emerged, which has attracted industry attention for its environmental protection and high efficiency. This article will introduce in detail the bleaching mechanism, implementation strategy and potential impact of this new technology on the papermaking industry.

With the increasingly stringent environmental regulations, the papermaking industry urgently needs to develop new environmentally friendly bleaching technologies. The combination of magnesium hydroxide and hydrogen peroxide as an emerging bleaching method can not only effectively improve the whiteness of pulp, but also avoid the environmental risks brought by traditional bleaching agents.

Basic principle:

Role of magnesium hydroxide: As an alkali source, magnesium hydroxide hydrolyzes in water to provide OH⁻, creating an ideal pH environment for the oxidative bleaching effect of hydrogen peroxide, and plays a buffering role in the bleaching process to maintain pH stability.

Role of hydrogen peroxide: Under alkaline conditions, the hydroxyl radicals (•OH) generated by the decomposition of hydrogen peroxide can oxidatively decompose the pigments in the pulp and effectively improve the whiteness.

Implementation method: In the pulping stage, magnesium hydroxide and hydrogen peroxide are added to the pulp in a certain proportion, and the bleaching process is optimized by controlling conditions such as pH value, temperature and reaction time.

Experimental method: The bleaching effect is evaluated by comparing the whiteness and optical properties of the pulp before and after bleaching, and the bleaching conditions are adjusted according to the experimental results to achieve the best bleaching effect.

Results and discussion: The experimental results show that the new bleaching technology can effectively improve the whiteness of pulp and reduce environmental pollution. pH value, temperature and time are the key factors affecting the bleaching effect. Suitable conditions can ensure the efficiency and environmental protection of the bleaching process.

Process optimization: By accurately controlling the addition amount of magnesium hydroxide and hydrogen peroxide and the bleaching conditions, the production cost can be reduced while ensuring the bleaching effect, and the process can be optimized.

The combined application of magnesium hydroxide and hydrogen peroxide provides a new green bleaching solution for the papermaking industry. This new technology not only improves the whiteness of pulp, but also significantly reduces the risk of environmental pollution, which is in line with the industrial trend of sustainable development.