Chemical industry particle technology

Liquid-liquid mixing has been widely used in chemical industries. The state of dispersion is determined by the balance of the break-up and coalescence of droplets. In the case of liquid-liquid mixing, the breakup of the droplet is accelerated in the impeller region. Although the droplet size distribution in the operation has been expressed by various PSD functions, the PSD function that is utilized the most is the normal PSD function. However, there is no physical background to apply the normal PSD function to the droplet size distribution. Additionally, when the droplet size distribution is expressed by various PSD functions, it becomes difficult to discuss the relationship between the parameters in PSD and operation conditions. This is one of the obstacles for developing particle technology. 

Chen, A., and Li, J. Particle aggregation in particle-fluid two-phase flow, in Fluidization 94—Science and Technology (the organizing committee of CJF-5, ed.), p. 254. Chemical Industry Press, Beijing, 1994. 

Diisocyanates are an important class of chemicals of commercial interest, which are frequently used in the manufacture of indoor materials. such as adhesives, coatings, foams and rubbers (Ulrich, 1989). In some types of particle board, the diisocyanates have replaced formaldehyde. Isocyanates are characterized by the electrophilic -N=C=0 group, which can easily react with molecules containing hydroxy groups, such as water or alcohols. On hydrolysis with water, primary amines are formed, while a reaction with alcohols leads to carbamates (urethanes). Polyurethane (PUR) products are then obtained from a polyaddition of diisocyanate and diol components. Compounds commonly used in industrial surface technology are 4,4 -diphenylmethane diisocyanate (MDI) and hexamethylene diisocyanate (HDI). The diisocyanate monomers are known as respiratory sensitizers and cause irritation of eyes, skin and mucous membrane. Therefore, polyisocyanates such as HDI-biuret and HDI-isocyanurate with a monomer content <0.5 % are used for industrial applications, and isocyanate monomers will not achieve high concentrations in ambient air. Nevertheless, it is desirable to measure even trace emissions from materials in private dwellings. 

The use of fluidization processing was developed mainly by the petroleum and chemical industries tor operations where the very high heat transter coefficients and the high degree ot uniformity ot temperature within the bed enabled the development ot processes, which would otherwise be impracticable. Fluidization technologies are nowadays used quite extensively in many industries where it is desirable to bring about intimate contact between small solid particles and a gas stream. 

Research into synthesis of nano-particles and nano-hybrids for use in spinning disc processing technology. Nano-catalysis for the fine chemical industry. 

The ability to control crystallization is a critical requirement in many technologies such as in the food, pharmaceutical and chemical industries. Crystallization parameters such as particle size, particle shape, particle morphology and polymorph selectivity determine the crystal properties and uses. The solution concentration, crystallization time, crystallization temperature, solvent and crystallization vessel all have an effect on the crystal parameters. In the past few decades, researchers have been busy searching for new ways to control crystallization. Self assembled monolayers are showing great promise in this field. The... 

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