For anyone involved in water treatment, understanding the fundamental chemistry behind flocculation is key to achieving optimal results. Aluminium Sulphate, a cornerstone chemical in this field, operates through a well-defined process of hydrolysis and particle aggregation. As a leading manufacturer and supplier of water treatment chemicals, we are committed to educating our clients on the efficacy and science behind our products, including Aluminium Sulphate (CAS 10043-01-3).

At its core, Aluminium Sulphate functions as a primary coagulant and flocculant. When introduced into water, especially water containing suspended colloidal particles which are often negatively charged, the Aluminium Sulphate molecule begins to dissociate. The key reactions involve the aluminum cation (Al³⁺) interacting with water molecules. This interaction leads to a series of hydrolysis steps:

Al³⁺ + 3H₂O ⇌ Al(OH)₃ + 3H⁺

This simplified equation shows the formation of aluminum hydroxide (Al(OH)₃), which is a positively charged colloidal species. In reality, the hydrolysis is more complex, forming various polynuclear aluminum hydroxy complexes. These positively charged aluminum species act as neutralizers for the negatively charged suspended particles in the water. They adsorb onto the surface of these particles, reducing their surface charge and overcoming the electrostatic repulsion that keeps them dispersed and stable.

Once the charges are neutralized, a process called 'sweep flocculation' can occur. The positively charged aluminum hydroxide species and the neutralized suspended particles begin to aggregate. As more of these complexes form and grow, they become large enough to be visible as 'flocs.' These flocs are essentially macroscopic aggregates of the original suspended solids, the aluminum hydroxide precipitate, and other impurities that get trapped within the forming structure.

The effectiveness of Aluminium Sulphate as a flocculant is influenced by several factors, including pH, temperature, and the presence of other ions in the water. The ideal pH range for effective floc formation with Aluminium Sulphate is typically between 6.0 and 7.5, although this can vary depending on the water's alkalinity. When water temperatures are low, the hydrolysis reactions and floc formation can slow down, potentially reducing efficiency. This is a critical consideration for industrial water treatment processes operating in cooler climates.

As a reliable Aluminium Sulphate supplier, we ensure our product is manufactured to high standards of purity to maximize its flocculation capabilities. Our non-ferric grade is particularly important for applications where discoloration is a concern. For those looking to buy Aluminium Sulphate or understand its chemical behavior, our technical team is available to provide detailed insights. Partnering with us means accessing not only a superior product but also the expertise that underlies its effective application in achieving clear and safe water.