Solvents design

For solvent design, in addition to the normal boiling point, liquid density, and the latent heat of vaporization solubility and related properties, as well as health and safety properties, must be estimated. Estimation methods for these properties are discussed next. 

Solubility and Related Measures. For the design of solvents to clean surfaces, to apply coating resins, and to swell cured elastomers, the Hansen solubility parameter  

Given estimates of these three solubility parameters, a solvent is likely to dissolve a solute when  

For other applications, like the selection of solvents for the liquid-liquid extraction of solutes from mixtures, solubility and related measures are determined on the basis of the liquid-phase activity coefficients, 7y, for solute-solvent pairs. Usually, for screening purposes, it is sufficient to estimate the liquid-phase activity coefficient at infinite dilution, 7, , using group-contribution methods. 

When considering solvent S for extraction of solute A from species B, Pretel and coworkers (1994) use the UNIFAC group-contribution method to obtain estimates of four solvent properties  

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Formulator s Dilemma. The regulatory discussion included a listing of solvents designated as HAP compounds. Emissions of these solvents are to be significantly reduced. For many appHcations this means that less is to be allowed. In a situation where the allowed VOC emission levels are also being reduced, the formulator would like to use the most effective solvents available. In the past, MEK and MIBK were frequently used as active solvents and aromatic hydrocarbons as diluents. These solvents have been popular because they are cost-effective. 

Karunanithi, A., Achenie, L. E. K. Gani, R. (2006), A computer aided molecular design framework for crystallization solvent design, Chemical Engineering Science, 61, 1243-1256. 

Karunanithi, A.T., Achenie, L.E.K., Gani, R., 2005, A Computer Aided Molecular Design Framework for Crystallization Solvent Design, Chemical Engineering Science, In Press. 

Section 2 gives a detailed description of the solvent design problem that is being addressed, section 3 describes a decomposition-based computer aided molecular... 

Flash point is one of the most important fire safety characteristics and hence it is a very important consideration in solvent design. The flammability limit of a solvent is characterized by its flash point, which is the temperature at which the mixture of air and vapor above the liquid can be ignited (Mullin, 1961). It is the lowest point at which the vapor pressure of a liquid will produce a flammable mixture. The flash point of the solvent can be estimated using the following group contribution method (ICAS, 2003)... 

Solvent design for crystallization of pharmaceutical products 4.2.6 Viscosity of the Solvent... 

The constraints in the general CAMD problem are first decomposed into two parts, namely pure component design part and mixture design part as shown in Figure 2. If we are interested in single compound solvent design, only the first part is needed while if we are interested in mixture design both parts are needed. 

Case Study 1 Cooling Crystallization Solvent Design... 

This problem encompasses two single compound CAMD problems, namely design of solvent and anti-solvent and then identification of optimal mixture pair and its composition. The single component solvent design problem is the same as in case study 1 (Sub-problems 1, 2 and 3). The 10 molecules that are designed in the first case study are considered here. The single component antisolvent design proceeds as follows... 

Since these constraints are the same, the same 2691 molecular structures generated for the single compound solvent design are generated in sub-problem 1. 

Since we do not have any mixture property constraints related to single compound anti-solvent design this sub-problem was ignored. 

Hostrup, M., Harper, P. M., Gani, R., 1999, Design of environmentally benign processes Integration of solvent design and separation process synthesis, Computers and Chemical Engineering, 23(1999) 1395-1414. 

Set-up the solvent design/selection problem defined in step 2 in ProCAMD. In ProCAMD, the information related to the CAMD problem is organized in terms of the following types ... 

What are the new factors in the area of green chemistry and solvent design We must view the problem from the perspective of environmental toxicology. In table 1.2... 

Separation processes (both liquid-liquid and gas-liquid) are a key element in many industrial processes. For this application, solvent molecules are built from UNIFAC submolecular groups, and the relevant properties of the new molecules such as distribution coefficients and selectivities are estimated. Strategies for the design of solvents for separation processes were initially formulated and later extended to better model the processes of solvent synthesis, solvent evaluation, and solvent screening. A method for solvent design for liquid-liquid extraction has been developed. 

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