2: Clarification mechanism of coagulant

Chemical coagulation is a process in which chemical agents (coagulants) are added to water treatment to make colloidal dispersion system destabilize and agglomerate. In the coagulation process, small suspended particles and colloidal impurities are aggregated into larger solid particles to separate particulate impurities from water, which is called coagulation clarification.

After adding coagulant into water, colloidal particles and other small particles can be polymerized into larger flocs through the comprehensive action of mixing, coagulation and flocculation. The whole process of coagulation and flocculation is called coagulation.

(1) Destabilization and condensation of colloids

Adding electrolyte to water can compress the electric double layer and destabilize the colloid. The main mechanism is that the electric double layer of colloidal particles in water is compressed or neutralized by adding aluminum salt or iron salt coagulant. The coagulant and raw water are mixed rapidly and evenly, and a series of chemical reactions are produced to destabilize. This process takes a short time, generally about 1 min. Some cationic polymers can also play a role in the destabilization and condensation of colloids in water. These polymers have a long chain structure and positive charge in water. Their destabilization and condensation of colloids in water is due to the interaction of van der Waals force adsorption and electrostatic attraction.

(2) Flocculation and formation of floc (alum)

The particle size of the initial flocculate formed by colloid destabilization and coagulation in water is generally more than 1 m. at this time, Brownian motion can no longer push them to collide and form larger particles. In order to make the initial flocs collide with each other to form large flocs, it is necessary to input additional energy into the water to produce a velocity gradient. Sometimes it is necessary to add organic polymer flocculant into water, and the adsorption bridging effect of long chain molecules of flocculant is used to improve the probability of collision and adhesion. Flocculation efficiency usually increases with the increase of flocculate concentration and flocculation time.

Compared with polyaluminum chloride, polyaluminum chloride has the advantages of high density, fast settling speed and wide pH adaptability; the coagulation effect is less affected by temperature than that of polyaluminum sulfate; however, when adding ferric salt, it should be noted that when the equipment is not in normal operation, the iron ions will make the effluent color, and may pollute the subsequent desalination equipment.

EFSA’s scientific advice will be used by risk managers (the European Commission, Member States) to inform any decisions they take on possible regulatory actions.

The surge in demand for interior and exterior paints and use of plastic across various end-use industries drive the global Lithopone market. Lithopone white pigment is used in paints and coating systems that find applications in residential and industrial landscapes. Hence, as the construction & building sector flourishes, the demand for building and architectural materials such as paints and coatings will increase. This trend is conducive for the Lithopone market growth. In addition, white plastic materials are increasingly being used in consumer products. Developments in plastic forming technology is anticipated to indirectly boost plastic production, thus, increasing the demand for white pigments during the forecast period.

In conclusion, wholesale lithopone MSDS quotes play a crucial role in ensuring the safe and responsible use of this important industrial pigment. By considering key factors such as product information, hazard identification, safety measures, emergency procedures, and regulatory compliance, businesses can make informed decisions when sourcing lithopone for their manufacturing processes. Ultimately, prioritizing safety and regulatory compliance is essential for a successful and sustainable industrial supply chain.

The overseas demand for Chinese TiO2 rose up by about 17% in 2016, which enabled an export increase of the manufacturers in China. As a fact, Chinese TiO2 is highly demanded in overseas markets, due to the comparable small price of the suppliers. The export of TiO2 is responsible for about one-third of the total output in China.

Following six months of phasing out the additive, titanium dioxide will be completely banned in the European Union starting August 7. France had previously banned the use of titanium dioxide in food starting in January 2020.