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    • In a decisive effort to simplify the

    2018-11-05

    In a decisive effort to simplify the alkyd reactor prediction–estimation problem and all monitoring/control problems associated with it, a novel linear integral model for conversion of catalase inhibitor functional group was developed in this study for predicting the progress of reaction in a typical batch operation based on empirical third-order rate model and wave propagation theory. The development of the new conversion model employs the knowledge that on the basis of a model augmented with wave particle behavior and driven by online measurements, the kinetics uncertainty could be robustly reconstructed via successive linearization and indefinite integration of the adjusted model. That is, with proper adjustment of parameters, the third-order rate model (1a) could be integrated analytically to obtain a generalized integral conversion model of the form (7) which could be linked to existing kinetics laws to yield adequate prediction of the entire reactor motion and the emerging product quality Except for the present work, the idea of using a kinetics model, modified based on wave propagation theory as a compensator network to approximate the motion and the trajectory of reaction in alkyd polymerization process has not been reported. The performance of the proposed method in yielding the present-time estimate of the key reactor variables that are related to product quality including; conversion viscosity, molecular weight, was compared with that of the standard geometric estimation method using data taken from the results of a laboratory scale synthesis of alkyd resin from oxy-polymerizable gmelina seed oil.
    Materials and methods
    Conclusion
    Introduction Increasing energy demand coupled with the depletion of fossil fuel resources and increasing environmental pollution has stimulated increasing interest in using H2 as a clean fuel. In fact, H2 has been proposed as a potential energy source due to its abundance, cleanliness and high energy yield. Unfortunately, the majority of H2 is produced from fossil fuels; only 4% of H2 is derived from other renewable sources (Parthasarathy and Narayanan, 2014). Because fossil fuels will be depleted by 2050, it is prudent to search for a sustainable and eco-friendly source of H2 generation (Ashekuzzaman and Jiang, 2014). Renewable technologies to produce H2 for fuel cell applications not only safeguard the environment but also provide a sustainable source of H2. Among the various H2 production methods, chemical looping reforming (CLR) seems to be a promising and environmentally friendly alternative (de Diego et al., 2009). In fact, CLR has been considered an alternative to catalytic autothermal steam reforming (de Diego et al., 2009; Ortiz et al., 2011). The main advantage of the CLR route is that the oxygen carrier (OC) is an oxide (usually a metal oxide (MeO)) (Pröll et al., 2010; Wang, 2014). As a result, air may be used instead of pure O2, and N2 is never mixed with H2. A CLR system consists of two interconnected reactors, designated the air (AR) and fuel reactors (FR) (Dueso et al., 2012). In the FR, fuel and steam are burned with an OC to form a synthesis gas (SG) (mixture of CO, H2, CO2, CH4, H2O, etc.) while OC particles are reduced to a metal (Me). The reduced metal is transferred into the AR, where it is oxidized with air. The regenerated material is then ready to start a new cycle. The major advantage of this process is that the heat needed for converting fuel to H2 can be supplied without costly O2 production, without mixing air with carbon containing fuel gases and without using part of the H2 produced in the process (de Diego et al., 2009). A N2-free gas stream containing concentrated H2 and CO is obtained from the reformer, avoiding dilution of the H2 with N2. If the H2 produced is to be used in fuel cells, it should be noted that the dilution of the H2 stream by N2 results in an increased anode overpotential during the operation of a proton exchange membrane fuel cell (PEMFC) (da Silva et al., 2012). H2 production via CLR of various fuels is currently being investigated intensively, and several papers on this subject have already been published. Moldenhauer and co-workers (Moldenhauer et al., 2012) performed a reaction between a nickel-based OC and liquid kerosene in a CLR reactor with continuous particle circulation. An injection system was constructed in which sulfur-free kerosene was evaporated, mixed with superheated steam and fed directly into a lab scale CLR reactor. Moldenhauer et al. showed that it is possible to use liquid fuel in a continuous CLR process and to achieve nearly complete fuel conversion. Kai et al. (Kai et al., 2012) implemented a process of separating H2 from SG through the chemical looping of a Fe-based catalyst as an oxygen-transfer material and a modified calcium oxide (CaO) as a CO2 sorbent in a fixed-bed reactor. Kai et al. achieved a hydrogen purity above 99.5% and a yield approaching 27.91 mmol/g Fe catalyst.