In fine chemical production, acid washing, alkaline washing, and water washing are key processes for removing salts, free acids and alkalis, metal ions, and colored by-products from the organic phase. These processes directly affect the purity and yield of the final product. However, many companies still rely on the traditional batch process of reactor agitation followed by settling and phase separation. A single washing cycle can take several hours, and gravity separation often results in incomplete separation due to the accumulation of emulsion layers, severe solvent entrainment, and significant batch-to-batch fluctuations in product purity. As production capacity and environmental requirements continue to increase, traditional batch washing has become a bottleneck restricting production efficiency and product quality.
Principle Innovation: Centrifugal Force Field Reshapes the Washing Process
The CWL-M Centrifugal Extractor utilizes a high-speed rotating centrifugal force field, generating hundreds of times the force of gravity. This enables the organic phase and washing water (acid/alkaline solution) to achieve micron-scale mixing and mass transfer, followed by forced separation within seconds. Compared with traditional gravity settling, mass transfer efficiency is increased by 5–8 times, while the processing time per stage is reduced to 1–3 minutes. The entire process operates continuously in a closed system, fundamentally reducing emulsion formation and entrainment.
Process Advantages: Quantitative Improvements in Water Washing, Alkaline Neutralization, and Acid Washing
Water Washing for Desalination:
Multi-stage counter-current water washing is adopted, reducing washing water consumption by 30%–50%. Salt residues in the organic phase can be consistently controlled below 200 ppm. After upgrading its process, a pesticide intermediate manufacturer reduced washing water consumption by 45% and achieved 6,000 hours of continuous operation without emulsion layer accumulation.
Alkaline Washing for Neutralization:
Acid-base neutralization and phase separation are completed simultaneously, significantly improving alkali utilization and enabling precise pH control. The pH of the outlet water can be stably maintained at 6.5–7.5. After adopting the CWL-150M Centrifugal Extractor, a pharmaceutical API manufacturer reduced manual intervention by 80%.
Acid Washing for Impurity Removal:
For phosphate ester products such as BDP, the centrifugal extractor can be integrated with a static mixer to complete the entire process of acid washing–filtration–centrifugal separation–coalescence purification, effectively removing impurities and meeting the requirements for low color and high product purity.
Application Data and Equipment Selection Support
Taking a fine chemical manufacturer as an example, the original 30 m³ reactor required 8–12 hours to complete the process of two acid washes, two alkaline washes, and two water washes. After switching to a three-stage counter-current CWL-M Centrifugal Extractor system, the process was converted to continuous operation, processing time was significantly shortened, solvent consumption was reduced by 20%–30%, and batch-to-batch product consistency was substantially improved. The equipment footprint is only 1/5–1/3 that of the traditional process, while corrosion-resistant materials enable operation with strong acid and strong alkaline systems.
Tiei Extraction provides comprehensive services covering process diagnosis, pilot-scale testing, and industrial integration. Customers can provide actual process materials for testing on the CWL-M Centrifugal Extractor, allowing optimization of parameters such as phase ratio, rotational speed, and number of stages. Data-driven process design helps customers reduce the risks associated with process upgrades.
Email: sales@tieiextraction.com
Whatsapp: +86 19069612820
