In modern industry, phosphoric acid is widely used in pharmaceuticals, food, fertilizers, and many other sectors. It serves not only as a rust inhibitor and food additive but also as an important raw material for phosphates, which are essential nutrients for life. Currently, phosphoric acid is mainly produced by two processes: the thermal process and the wet process. Wet-process phosphoric acid, due to its lower energy consumption and higher output (accounting for approximately 85%–90% of total production), is gradually replacing thermal-process phosphoric acid. However, during the production of wet-process phosphoric acid, impurities from the phosphate rock raw material contaminate the finished phosphoric acid, limiting its purity and making it difficult to meet the requirements of high-end products. Therefore, phosphoric acid purification technology is crucial.
In industries such as metal surface treatment, aluminum and its alloys generate large amounts of waste phosphoric acid liquid during anodizing and chemical polishing processes. Anodizing forms an oxide film on the surface of aluminum products by applying an external current, while chemical polishing uses a mixture of phosphoric and nitric acids to improve metal surface smoothness. However, the water washing steps in production produce large volumes of acidic wastewater. In chemical polishing, aluminum continuously accumulates in the polishing solution, preventing its reuse and resulting in mixed acid waste liquid. Direct discharge of these waste acids would cause severe environmental pollution. Notably, waste acids discharged from the non-ferrous metal industry contain high levels of heavy metals, contaminating rivers and groundwater. Consequently, discharge standards for waste acids are becoming increasingly stringent, and the resource utilization, detoxification, and recycling of waste acids have become inevitable trends.
Existing waste phosphoric acid treatment methods on the market have many drawbacks. The ion exchange resin method, when treating phosphoric acid solutions containing aluminum, requires large amounts of resin due to the high concentrations of aluminum and phosphoric acid, leading to high production costs. Additionally, the presence of mixed nitric acid degrades the resin quality, making it difficult to achieve high-purity phosphoric acid recovery. The organic solvent extraction method uses alcohols, ketones, and other organic solvents to extract phosphoric acid, but the separation efficiency for aluminum and the extraction efficiency for phosphoric acid are low, failing to achieve ideal results.
To address these issues, Guochu Technology (Xiamen) Co., Ltd., leveraging its core advantages in membrane separation technology, has successfully developed a series of innovative phosphoric acid purification technologies. This technology employs a nanoscale physical separation method to remove metal impurity ions without phase conversion. It features simple operation, a short process flow, no need for heating or pressurization, high safety, low energy consumption, and nearly negligible operating costs. Moreover, the equipment has a small footprint and is easy to operate in large-scale production, greatly improving the efficiency and recovery rate of phosphoric acid purification.
Technical features and advantages:
Suitable for purification of phosphoric acid with high acid concentration and high levels of ionic impurities
No heating or pressurization required during the phosphoric acid purification process, ensuring high safety and extremely low energy consumption
Advantages in both phosphoric acid recovery rate and recovered phosphoric acid concentration
Guochu Technology's acid purification technology is not limited to phosphoric acid; it can also be applied to the recovery and purification of various waste acids such as hydrochloric acid, nitric acid, and sulfuric acid, providing comprehensive and robust technical support for industrial waste acid treatment.
Since its establishment, Guochu Technology has been dedicated to the promotion and application of novel separation technologies. The company has accumulated extensive experience in specialized membrane applications across many industries, including biopharmaceuticals, food and beverages, fermentation, deep processing of agricultural products, plant extraction, petrochemicals, environmental water treatment, gas separation, and chemicals. In the future, Guochu Technology will continue to deepen technological innovation, providing professional and efficient solutions for waste phosphoric acid liquid recovery and other waste acid treatment to more industries, thereby supporting green and sustainable development across various sectors.
