End-use Properties Of Products Research Articles

BAYESIAN OPTIMIZATION OF CRYSTALLIZATION PROCESSES TO GUARANTEE END-USE PRODUCT PROPERTIES

For pharmaceutical solid products, the issue of reproducibly obtaining their desired end-use properties depending on crystal size and form is the main problem to be addressed and solved in process development. Lacking a reliable first-principles model of a crystallization process, a Bayesian optimization algorithm is proposed. On this basis, a short sequence of experimental runs for pinpointing operating conditions that maximize the probability of successfully complying with end-use product properties is defined. Bayesian optimization can take advantage of the full information provided by the sequence of experiments made using a probabilistic model of the probability of success based on a one-class classification method. The proposed algorithm’s performance is tested in silico using the crystallization and formulation of an API product where success is about fulfilling a dissolution profile as required by the FDA. Results obtained demonstrate that the sequence of generated experiments allows pinpointing operating conditions for reproducible quality.

Probability-Based Design of Experiments for Batch Process Optimization with End-Point Specifications

Consistently complying with end-point specifications, mainly end-use product properties, is a key issue to the competitiveness of batch processes. To maximize in some way the probability of observing successful runs, a series of experiments is specifically designed to pinpoint the smallest operating region that guarantees that end-point conditions can meet their desired targets. On the basis of data-driven modeling of the underlying binomial probability of success, the proposed methodology seeks to trade off improving parameter precision with experimenting in a reduced region where there is a high probability of satisfying end-point specifications. Two case studies are used to demonstrate the efficacy of the probability-based optimal design of experiments to find optimal policies for runs involving stochastic binary outcomes. Run-to-run improvement of the success rate for the operating policy in the acetoacetylation of pyrrole with diketene is first discussed. Results obtained for emulsion polymerization ...

Online Inferential Measurement of Conversion and Molar Mass in Emulsion Polymerization Controlled by Chain Transfer

Polymer molecular weight significantly influences end-use product properties such as elasticity, toughness, and tensile strength. A chain transfer agent (CTA), tertiary-dodecyl mercaptan was utilized to control molecular weight. Calorimetry enables product property estimation by exploiting the knowledge inferred from mass and energy balances. We developed a calorimetry model to estimate conversion and molecular weight of polystyrene for emulsion polymerization in batch and semibatch operations. The model also provides the effects of CTA in variable modes of operation. We found that the CTA is significantly able to reduce molecular weight in semibatch compared to batch reactor operation. The calorimetry model was found to be suitable for monitoring the emulsion polymerization process and to track the evolution of molar mass while implementing process optimization and control.

Among the trends for a modern chemical engineering, the third paradigm: The time and length multiscale approach as an efficient tool for process intensification and product design and engineering

To respond to the changing needs of the chemical and related industries in order both to meet today's economy demands and to remain competitive in global trade, a modern chemical engineering is vital to satisfy both the market requirements for specific nano and microscale end-use properties of products, and the social and environmental constraints of industrial meso and macroscale processes. Thus an integrated system approach of complex multidisciplinary, non-linear, non-equilibrium processes and phenomena occurring on different length and time scales of the supply chain is required. That is, a good understanding of how phenomena at a smaller length-scale relates to properties and behaviour at a longer length-scale is necessary (from the molecular-scale to the production-scales). This has been defined as the triplet “molecular Processes-Product-Process (3PE)” integrated multiscale approach of chemical engineering. Indeed a modern chemical engineering can be summarized by four main objectives: (1) Increase productivity and selectivity through intensification of intelligent operations and a multiscale approach to processes control: nano and micro-tailoring of materials with controlled structure. (2) Design novel equipment based on scientific principles and new production methods: process intensification using multifunctional reactors and micro-engineering for micro structured equipment. (3) Manufacturing end-use properties to synthesize structured products, combining several functions required by the customer with a special emphasis on complex fluids and solid technology, necessating molecular modeling, polymorph prediction and sensor development. (4) Implement multiscale application of computational chemical engineering modeling and simulation to real-life situations from the molecular-scale to the production-scale, e.g., in order to understand how phenomena at a smaller length-scale relate to properties and behaviour at a longer length-scale. The presentation will emphasize the 3PE multiscale approach of chemical engineering for investigations in the previous objectives and on its success due to the today's considerable progress in the use of scientific instrumentation, in modeling, simulation and computer-aided tools, and in the systematic design methods.

Simultaneous Controllability of PSD and MWD in Emulsion Polymerisation

A sensitivity study of particle size distribution (PSD) and molecular weight distribution (MWD) responses to perturbations in initiator, surfactant, monomer and chain transfer agent in a semi-batch emulsion polymerisation is presented. The objective is to provide a systematic study on the ability to simultaneously control both PSD and MWD, towards inferential control of end-use product properties. This would lead towards identification of the practical feasible regions of operability. All inputs appeared to have an intrinsic and simultaneous influence on end-time PSD and MWD. Trends shown in experimental results have been explained in a mechanistic sense and also compared to simulation results from a combined PSD/MWD population balance model. The preliminary comparison between experiment and simulation highlights areas to be focussed on with respect to model improvement.

Online inferential product attribute estimation for optimal operation of emulsion terpolymerisation: Application to styrene/MMA/MA

An advanced model for process design and control of emulsion terpolymerisation was developed. A test case of emulsion terpolymerisation of styrene (Sty), methyl methacrylate (MMA) and methyl acrylate (MA) was investigated on state of the art facilities for predicting, optimising and control end-use product properties including global and individual conversions, terpolymer composition, the average particle diameter and concentration, glass transition temperature, molecular weight distribution, the number- and weight-average molecular weights and particle size distribution. The model equations include diffusion-controlled kinetics at high monomer conversions, where transition from a ‘zero–one’ to a ‘pseudo-bulk’ regime occurs. Transport equations are used to describe the system transients for batch and semi-batch processes. The particle evolution is described by population balance equations which comprised a set of integro-partial differential and nonlinear algebraic equations. Backward finite difference approximation method is used to discretise the population equation and converts them from partial differential equations to ordinary differential equations. The model predictions were experimentally validated in the laboratory and were found to be in excellent agreement, thus paving the way for further application of the model.

In the frame of globalization, some tracks for the future of chemical and process engineering

In today's economy, chemical engineering must respond to the changing needs of the chemical process industry in order to meet market demands. The evolution of chemical engineering is necessary to remain competitive in global trade. The ability of chemical engineering to cope with managing complex systems met in scientific and technological problems is addressed in this paper. Chemical Engineering is vital for sustainability: to satisfy both the market requirements for specific end-use properties of products and the social and environmental constraints of industrial-scale processes. An integrated system approach of complex multidisciplinary, non-linear non-equilibrium processes and phenomena occurring on different length and time scales is required. This will be obtained due to breakthroughs in molecular modeling, scientific instrumentation and related signal processing and powerful computational tools. The future of chemical engineering can be summarized by four main objectives: (1) Increase productivity and selectivity through intensification of intelligent operations and a multiscale approach to processes control; (2) Design novel equipment based on scientific principles and new production methods: process intensification using multifunctional reactors and microengineering and microtechnology (3) Extend chemical engineering methodology to product design and engineering using the "triplet 3PE molecular Processes-Product-Process Engineering" approach; (4) Implement multiscale application of computational chemical engineering modeling and simulation to real-life situations from the molecular scale to the production scale.

Managing complex systems: some trends for the future of chemical and process engineering

In today's economy, chemical engineering must respond to the changing needs of the chemical process industry in order to meet market demands. The evolution of chemical engineering is necessary to remain competitive in global trade. The ability of chemical engineering to cope with managing complex systems met in scientific and technological problems is addressed in this paper. Chemical engineering is vital for sustainability: to satisfy both the market requirements for specific end-use properties of products and the social and environmental constraints of industrial-scale processes. An integrated system approach of complex multidisciplinary, non-linear, non-equilibrium processes and phenomena occurring on different length and time scales is required. This will be obtained due to breakthroughs in molecular modelling, scientific instrumentation and related signal processing and powerful computational tools. The future of chemical engineering can be summarized by four main objectives: (1) Increase productivity and selectivity through intensification of intelligent operations and a multiscale approach to process control; (2) Design novel equipment based on scientific principles and new production methods: process intensification; (3) Extend chemical engineering methodology to product design and engineering using the “triplet 3PE molecular Processes-Product-Process Engineering” approach; (4) Implement multiscale application of computational chemical engineering modelling and simulation to real-life situations from the molecular scale to the production scale.

Market Demand versus Technological Development: the Future of Chemical Engineering

In today’s economy, Chemical Engineering must respond to the changing needs of the chemical process industry in order to meet market demands. The evolution of chemical engineering is necessary to remain competitive in global trade. The ability of chemical engineering to cope with scientific and technological problems is addressed in this paper. Chemical Engineering is vital for sustainability: to satisfy both the market requirements for specific end-use properties of products and the social and environmental constraints of industrial-scale processes. A multidisciplinary, multiscale approach to chemical engineering is evolving due to breakthroughs in molecular modelling, scientific instrumentation and related signal processing and powerful computational tools. The future of chemical engineering can be summarized by four main objectives: (1) Increase productivity and selectivity through intensification of intelligent operations and a multiscale approach to process control; (2) Design novel equipment based on scientific principles and new production methods: process intensification; (3) Extend chemical engineering methodology to product design and product focussed processing using the 3P Engineering “molecular Processes-Product-Process” approach; (4) Implement multiscale application of computational chemical engineering modelling and simulation to real-life situations from the molecular scale to the production scale.

The triplet “molecular processes–product–process” engineering: the future of chemical engineering ?

Today chemical engineering has to answer to the changing needs of the chemical and related process industries and to meet the market demands. Being a key to survival in globalization of trade and competition, the evolution of chemical engineering is thus necessary. Its ability to cope with the scientific and technological problems encountered will be appraised in this paper. To satisfy both the markets requirements for specific end-use properties of products and the social and environmental constraints of the industrial-scale processes, it is shown that a necessary progress is coming via a multidisciplinary and a time and length multiscale approach. This will be obtained due to breakthroughs in molecular modelling, scientific instrumentation and related signal processing and powerful computational tools. For the future of chemical engineering four main objectives are concerned: (a) to increase productivity and selectivity through intelligent operations via intensification and multiscale control of processes; (b) to design novel equipment based on scientific principles and new methods of production: process intensification; (c) to extend chemical engineering methodology to product focussed engineering, i.e. manufacturing and synthesizing end-use properties required by the customer, which needs a triplet “molecular processes–product–process” engineering; (d) to implement multiscale application of computational chemical engineering modelling and simulation to real-life situations, from the molecular scale to the overall complex production scale.