Market status and recycling dilemma of magnesium hydroxide aluminum-plastic panels

According to the "2023 Global Green Building Materials Development Report", the market size of magnesium hydroxide aluminum-plastic panels has reached US$6.7 billion, with an annual growth rate of more than 8%. Its core advantages are:

- Environmental properties: magnesium hydroxide (Mg(OH)₂) as a flame retardant, compared with traditional halogen flame retardants, does not release toxic gases when burned;

- Composite performance: The aluminum layer provides strength, and the plastic core material (mostly polyethylene PE) achieves lightweight, and the overall cost is 30% lower than that of pure metal sheets;

- Policy-driven: EU REACH regulations and China's "dual carbon" policy both list such low-VOC (volatile organic compound) materials as recommended products.

However, its composite structure (aluminum layer + plastic + magnesium hydroxide filling layer) makes traditional recycling methods inefficient:

1. Mechanical crushing can only separate aluminum fragments, and plastic cannot be reused after mixing with magnesium hydroxide powder;

2. Although incineration can recycle aluminum, magnesium hydroxide decomposes into magnesium oxide at high temperatures and produces a large amount of carbon dioxide;

3. Landfill disposal causes waste of aluminum resources, and the degradation cycle of plastic is as long as 500 years.

Industry data shows that the total amount of discarded aluminum-plastic panels in the world will exceed 1.8 million tons in 2022, but the recycling rate is less than 15%, and the technical bottleneck needs to be broken through urgently.

2. Recycling technology breakthrough: three-step separation method and low-temperature catalytic cracking

In 2023, the Fraunhofer Institute in Germany and the team from Tsinghua University in China jointly released the "White Paper on Efficient Recycling of Aluminum-Plastic Composites", proposing two key technological innovations:

1. Solvent three-step separation method

The material is peeled off layer by layer through a customized solvent system:

- Step 1: Soak in a citric acid solution with pH=3 to dissolve the oxide film on the surface of the aluminum layer;

- Step 2: Use a xylene-ethanol mixed solvent (volume ratio 7:3) to soften the PE layer at 80°C and mechanically peel off the complete aluminum foil;

- Step 3: The remaining plastic-magnesium hydroxide mixture is centrifuged to obtain Mg(OH)₂ powder with a purity of >98%.

Experiments show that the aluminum recovery rate of this method is 95%, the plastic recovery rate is 89%, and the solvent can be recycled more than 10 times, reducing the overall cost by 40%.

2. Low-temperature catalytic cracking technology

For contaminated waste aluminum-plastic panels (such as adhesive residues), the research team developed a new ZSM-5 molecular sieve catalyst that decomposes plastic into diesel fractions (C10-C20 hydrocarbons) at a low temperature of 380°C while maintaining the stability of the magnesium hydroxide structure.

- Product value: 0.5 tons of fuel oil, 0.3 tons of aluminum and 0.15 tons of magnesium hydroxide can be produced per ton of waste;

- Carbon emissions: 72% less than direct incineration;

- Economic efficiency: The processing cost is 60% of the traditional pyrolysis method, and the investment payback period is shortened to 3 years.

3. Synergy of the industrial chain: a closed loop from recycling to regeneration manufacturing

The progress of recycling technology is reconstructing the entire life cycle of magnesium hydroxide aluminum-plastic panels:

1. Intelligent recycling network

- Sorting upgrade: Spain's Reciclamix company launched an AI visual sorting system, which uses near-infrared spectroscopy (NIR) to identify different brands of aluminum-plastic panels with a sorting accuracy of 99%;

- Distributed processing: Small cracking devices can be installed on construction sites to achieve "source recycling - on-site processing".

2. High-end recycled materials

- Aluminum foil recycling: Japan's UACJ Group uses electrolytic refining technology to purify recycled aluminum to 99.9% for new energy vehicle battery shells;

- High-value utilization of plastics: Germany's BASF will modify recycled PE into flame-retardant composite materials, with a strength 15% higher than that of virgin materials;

- Magnesium hydroxide recycling: China's Qinghai Salt Lake Group will use the recycled Mg(OH)₂ to produce flame-retardant cables, reducing costs by 28%.

3. Improvement of policies and standards

- The EU plans to increase the recycling rate of aluminum-plastic panels to 50% by 2025;

- China's "Specifications for the Resource Utilization of Construction Waste" adds technical clauses for the recycling of aluminum-plastic panels;

- The US UL certification introduces "recycled content labels" to encourage downstream manufacturers to purchase recycled materials.

4. Future trends: from technological breakthroughs to business model innovation

As recycling technology matures, the industry will present three major development directions:

1. BIM (Building Information Model) + Recycling: Embed material traceability codes in the design stage to optimize the disassembly path;

2. Extended Producer Responsibility (EPR): It is mandatory for aluminum-plastic panel manufacturers to establish a recycling system. For example, the French Veolia Environment Group has implemented the policy of "recycling 0.8 tons of old materials for every 1 ton of new products sold";

3. Carbon trading incentives: Recycling companies can obtain carbon credits by reducing carbon emissions. It is estimated that by 2030, each ton of aluminum-plastic panel recycling will generate $120 in carbon revenue.

The breakthrough in the recycling technology of magnesium hydroxide aluminum-plastic panels marks the green building materials industry's move from "environmentally friendly material substitution" to a new stage of "full life cycle management". With the optimization of separation processes, the high value of recycled materials and the improvement of the policy system, this technology is expected to drive the global circular economy to grow by US$20 billion within five years. For construction companies, early layout of recycling channels and investment in recycling technologies will become the key to seizing the next round of market opportunities.