Effect of Process Parameters

Yield graft rubber = ratio of graft rubber to total rubber 

Graft density = average number of graft chains per grafted rubber molecule 

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The application of a selective pyrolysis process to the recovery of chemicals from waste PU foam is described. The reaction conditions are controlled so that target products can be collected directly from the waste stream in high yields. Molecular beam mass spectrometry is used in small-scale experiments to analyse the reaction products in real time, enabling the effects of process parameters such as temperature, catalysts and co-reagents to be quickly screened. Fixed bed and fluidised bed reactors are used to provide products for conventional chemical analysis to determine material balances and to test the concept under larger scale conditions. Results are presented for the recycling of PU foams from vehicle seats and refrigerators. 12 refs. 

In summary, the Avada process is an excellent example of process intensification to achieve higher energy efficiency and reduction of waste streams due to the use of a solid acid catalyst. The successful application of supported HP As for the production of ethyl acetate paves the way for future applications of supported HP As in new green processes for the production of other chemicals, fuels and lubricants. Our results also show that application of characterization techniques enables a better understanding of the effects of process parameters on reactivity and the eventual rational design of more active catalysts. 

Effect of Process Parameters on Short Contact Time Conversions... 

Kasahara, S. et al., Effects of process parameters of the IS process on total thermal efficiency to produce hydrogen from water, /. Chem. Eng. Jpn., 36, 887, 2003. 

El-Belghiti K, Rabhi Z and Vorobiev E. 2007. Effect of process parameters on solute centrifugal extraction from electropermeabilized carrot gratings. Food Bioprod Process 85(1) 24—28. 

The study of the effects of process parameters reveals that (1) methane can be substantially reduced by higher pressure, shorter contact time, lower temperature, and lower H2/C0 ratio and (2) the aromatics production is greatly favored by lower H2/CO ratio at moderate temperature. 

B.H. Lee, I.G. Kim, S.W. Cho, and S.H. Lee, Effect of process parameters on the characteristics of indium tin oxide thin film for flat panel display application, Thin Solid Films, 302 25-30, 1997. 

In many atomization processes, physical phenomena involved have not yet been understood to such an extent that mean droplet size could be expressed with equations derived directly from first principles, although some attempts have been made to predict droplet size and velocity distributions in sprays through maximum entropy principle.I252 432] Therefore, the correlations proposed by numerous studies on droplet size distributions are mainly empirical in nature. However, the empirical correlations prove to be a practical way to determine droplet sizes from process parameters and relevant physical properties of liquid and gas involved. In addition, these previous studies have provided insightful information about the effects of process parameters and material properties on droplet sizes. 

In the following sections, the correlations for droplet sizes generated by different types of atomizers will be summarized, and the effects of process parameters and material properties on droplet sizes will be discussed on the basis of the analytical and experimental studies available in published literature. 

In fan spray atomization, the effects of process parameters on the mean droplet size are similar to those in pressure-swirl atomization. In general, the mean droplet size increases with an increase in liquid viscosity, surface tension, and/or liquid sheet thickness and length. It decreases with increasing liquid velocity, liquid density, gas density, spray angle, and/or relative velocity between liquid and surrounding air. 

The studies on the performance of effervescent atomizer have been very limited as compared to those described above. However, the results of droplet size measurements made by Lefebvre et al.t87] for the effervescent atomizer provided insightful information about the effects of process parameters on droplet size. Their analysis of the experimental data suggested that the atomization quality by the effervescent atomizer is generally quite high. Better atomization may be achieved by generating small bubbles. Droplet size distribution may follow the Rosin-Rammler distribution pattern with the parameter q ranging from 1 to 2 for a gas to liquid ratio up to 0.2, and a liquid injection pressure from 34.5 to 345 kPa. The mean droplet size decreases with an increase in the gas to liquid ratio and/or liquid injection pressure. Any factor that tends to impair atomization quality, and increase the mean droplet size (for example, decreasing gas to liquid ratio and/or injection pressure) also leads to a more mono-disperse spray. 

Regarding the effects of process parameters on gas atomization of melts, modeling and experimental studies l63 l64 324l revealed that the mass median droplet diameter decreases with increasing atomization gas pressure and gas to metal mass flow rate ratio. The standard deviation decreases with increasing gas to metal mass flow rate ratio. As the melt superheat increases, both the mass median droplet diameter and the standard deviation decrease. 

Table 26.1 Effect of process parameters on hypochlorite concentration. 

Danilova-Volkovskaya G.M. The effect of processing parameters and modifiers on the properties of polypropylene and PP-based composite materials. — Doctoral Thesis, (technical sciences). 2005, p. 273. 

There are few studies in literature reporting pure gas permeabilities as well as separation factors of mixtures. Vuren et al. (1987) reported Knudsen diffusion behavior of pure gases for y-alumina membranes with a mean pore radius of 1.2 nm. Separation experiments with a 1 1 H2/N2 mixture showed, that the theoretical Knudsen separation factor [of 3.7, Equation 6.4)j for this mixture could be obtained (Keizer et al. 1988 see also Figure 6.2). In Figure 6.2, the effect of process parameters is also demonstrated. The separation factor is a function of the pressure ratio over the membrane, which is the ratio of the pressure on the permeate-side to that on the feed-side. For pressure ratios approaching unity, which means the pressure on both sides of the... 

In this work the effect of process parameters on the amination of iBuOH to (iBu)2NH was studied over V-modified Raney nickel. V is known to increase the yield of amines and the stability of catalyst (4,5). Factorial experimental design was used to describe the conversion of alcohol, and the yield and selectivity of secondary amine as a function of reaction temperature, space velocity and NH3/iBuOH molar ratio. 

Jeyanthi, R., Mehta, R.C., Thanoo, B.C., and Deluca, P.P. (1997). Effect of processing parameters on the properties of peptide-containing PLGA microspheres. J. Microencapsulation, 14, 163-174. 

The efficacy of the biological mercury removal process has been adequately demonstrated from a microbiological and biochemical viewpoint. The kinetics of the biological process, bioreactor design and the the effects of process parameters such as aeration rate, SRT and HRT variations on removal of... 

Dewettinck, K., Vanhoutte, B., Foubert, I., Huyghebaert, A. 2004. Milk fat. 1. Effect of process parameters on milkfat fractionation. In, Advances in Fractionation and Separation Processes for Novel Dairy Applications. Bulletin, No. 389, International Dairy Federation, Brussels, pp. 97-103. 

TABLE 19.14 Summary of Effects of Process Parameters on Coal Pyrolysis... 

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