In the advanced treatment of industrial wastewater, the purification and adsorption of exhaust gases, and the harmless decomposition of solid waste, silica is providing new solutions for pollution control as an "environmental purifier." This seemingly ordinary white powder, with its large specific surface area and abundant surface active groups, exhibits excellent performance in pollutant adsorption and catalytic degradation — from removing heavy metals in water to purifying VOCs in the air, from treating industrial waste residues to remediating soil pollution. The microstructure of silica is quietly contributing to environmental protection.

一、The "Adsorption Purifier" in Water Treatment

The purification of industrial wastewater and domestic sewage is a key issue in environmental protection. Silica improves water quality through precise adsorption:

Efficient removal of heavy metal ions: Hydroxyl groups on the surface of silica can form stable complexes with heavy metal ions (such as Pb²⁺, Cu²⁺, Cr⁶⁺), with an adsorption capacity for Pb²⁺ reaching over 150mg/g and a removal rate of 99%. In electroplating wastewater treatment, the concentration of heavy metals in effluent treated with silica is below 0.1mg/L, meeting national first-class discharge standards.

Adsorption and degradation of organic pollutants: The porous structure of silica can adsorb organic pollutants such as dyes and phenols in water, with an adsorption rate of over 90% for methyl orange. By loading photocatalysts like TiO₂, organic pollutants can be completely degraded under light, with a mineralization rate of 85%, solving the problem of secondary pollution after adsorption saturation.

Water softening and purification: Silica can adsorb calcium and magnesium ions in water to reduce water hardness, while removing odorous substances. In drinking water purification, filter materials added with silica can reduce water turbidity from 5NTU to below 0.5NTU, significantly improving taste.

The application of silica in water treatment has advantages such as large adsorption capacity, high selectivity, and reusability, providing an economical and efficient solution for the purification of complex water quality, especially showing unique value in the treatment of heavy metal pollution and refractory organic compounds.

二、The "Filtration Adsorber" in Waste Gas Treatment

The purification of industrial waste gas and automobile exhaust is crucial for improving air quality. Silica enables waste gas to meet emission standards through multiple mechanisms:

Adsorption and recovery of VOCs: Silica has an adsorption capacity of 20%-30% (mass ratio) for volatile organic compounds (VOCs) such as benzene, toluene, and xylene, with good desorption performance. In spray painting waste gas treatment, the silica adsorption-thermal desorption process achieves a VOCs removal rate of over 95%, and the purity of recovered solvents reaches 90%, realizing a win-win situation of resource recovery and pollution control.

Synergistic enhancement of flue gas desulfurization and denitrification: In wet desulfurization, silica can improve the dispersibility and reactivity of desulfurizers, increasing desulfurization efficiency from 90% to over 98% and reducing desulfurizer dosage by 10%-15%. By loading active components, it can also achieve denitrification simultaneously, with a NOx removal rate of 80%, meeting ultra-low emission standards.

Auxiliary purification of automobile exhaust: As a carrier for automobile exhaust catalysts, silica can improve the dispersion of precious metal active components, increasing the catalyst's CO conversion rate by 10% and hydrocarbon conversion rate by 15%. Meanwhile, its high-temperature resistance ensures the catalyst remains stable at high temperatures, extending its service life.

In waste gas treatment, silica not only efficiently adsorbs pollutants but also acts as a catalyst carrier to enhance reaction efficiency, providing strong support for the advanced treatment of industrial waste gas and mobile source pollution, and helping to improve air quality.

三、The "Stabilization Assistant" in Solid Waste Treatment

The harmless treatment of industrial solid waste and hazardous waste is a difficult point in environmental protection. Silica reduces pollution risks through stabilization:

Stabilization of heavy metal waste residues: Silica can form stable silicates or complexes with heavy metals in solid waste, reducing the leaching toxicity of heavy metals, with leaching concentrations dropping to below 1/10 of national standards. In electroplating sludge treatment, adding 10%-15% silica can make the sludge meet landfill standards, avoiding secondary pollution from heavy metals.

Harmless treatment of waste incineration fly ash: Silica can adsorb dioxins and heavy metals in fly ash, reducing dioxin content from 50ng-TEQ/kg to below 5ng-TEQ/kg, while reducing the corrosiveness of fly ash. The treated fly ash can be used for resource utilization such as brick-making, achieving "reduction, harmlessness, and resource utilization."

Promotion of agricultural waste composting: In composting of agricultural wastes such as straw, silica can adjust the air permeability and water retention of the compost pile, promote microbial activity, shorten the composting time from 30 days to 20 days, increase the organic matter content of compost products by 10%, and reduce heavy metal content by 20%.

In solid waste treatment, silica reduces the mobility and toxicity of pollutants through the synergistic effect of physical adsorption and chemical stabilization, creating conditions for the safe disposal and resource utilization of solid waste, and promoting the development of circular economy.



101 Methyl Silicone Gum-Mingyi Silicone