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To address the rising need of sustainable solutions in electronic devices, the development of electronically conductive composites based on lightweight but mechanically strong wood structures is highly desirable. Here, a facile approach for the fabrication of highly conductive wood/polypyrrole composites through top-down modification of native lignin followed by polymerization of pyrrole in wood cell wall. By sodium sulfite treatment under neutral condition, sulfonated wood veneers with increased porosity but well-preserved cell wall structure containing native lignin and lignosulfonates are obtained. The wood structure has a content of sulfonic groups up to 343 µmol g−1 owing to in situ sulfonated lignin which facilitates subsequent oxidative polymerization of pyrrole, achieving a weight gain of polypyrrole as high as 35 wt%. The lignosulfonates in the wood structure act as dopant and stabilizer for the synthesized polypyrrole. The composite reaches a high conductivity of 186 S m−1 and a specific pseudocapacitance of 1.71 F cm−2 at the current density of 8.0 mA cm−2. These results indicate that tailoring the wood/polymer interface in the cell wall and activating the redox activity of native lignin by sulfonation are important strategies for the fabrication of porous and lightweight wood/conductive polymer composites with potential for sustainable energy applications., QC 20230602

This second volume is based on all questions addressed during the presentations.

Chemithermomechanical pulp (CTMP) is often used in middle layers of multiply paperboards due to its high bulk at specified strength. Such a CTMP should consist of well-separated undamaged fibres with sufficient bonding capacity. The basic objective of this work is to examine the effect of refining on bulk, taking into account conditions such as temperature, sulphonation, refining gap and refiner size. First stage CTMP made from Norway spruce (Picea abies) were produced in pilot and mill scale trials. Two new parameters, Equivalent temperature related to softness and Refining gentleness are introduced that take into account refining conditions as actual temperature, softening temperature, bound sulphonate content, refining gap and refiner diameter. The results show that bulk increases linearly with refining gentleness.

In this paper we present the results of a feature importance analysis of a chemical sulphonation process. The task consists of predicting the neutralization number (NT), which is a metric that characterizes the product quality of active detergents. The prediction is based on a dataset of environmental measurements, sampled from an industrial chemical process. We used a soft-sensing approach, that is, predicting a variable of interest based on other process variables, instead of directly sensing the variable of interest. Reasons for doing so range from expensive sensory hardware to harsh environments, e.g., inside a chemical reactor. The aim of this study was to explore and detect which variables are the most relevant for predicting product quality, and to what degree of precision. We trained regression models based on linear regression, regression tree and random forest. A random forest model was used to rank the predictor variables by importance. Then, we trained the models in a forward-selection style by adding one feature at a time, starting with the most important one. Our results show that it is sufficient to use the top 3 important variables, out of the 8 variables, to achieve satisfactory prediction results. On the other hand, Random Forest obtained the best result when trained with all variables., ISBN för värdpublikation: 978-1-7281-6389-5, Productive4.0

In this paper we present the results of a feature importance analysis of a chemical sulphonation process. The task consists of predicting the neutralization number (NT), which is a metric that characterizes the product quality of active detergents. The prediction is based on a dataset of environmental measurements, sampled from an industrial chemical process. We used a soft-sensing approach, that is, predicting a variable of interest based on other process variables, instead of directly sensing the variable of interest. Reasons for doing so range from expensive sensory hardware to harsh environments, e.g., inside a chemical reactor. The aim of this study was to explore and detect which variables are the most relevant for predicting product quality, and to what degree of precision. We trained regression models based on linear regression, regression tree and random forest. A random forest model was used to rank the predictor variables by importance. Then, we trained the models in a forward-selection style by adding one feature at a time, starting with the most important one. Our results show that it is sufficient to use the top 3 important variables, out of the 8 variables, to achieve satisfactory prediction results. On the other hand, Random Forest obtained the best result when trained with all variables., ISBN för värdpublikation: 978-1-7281-6389-5, Productive4.0

Study on the electrical energy generated from a single fuel cell using a synthesized solid electrolyte membrane from polyisoprene that was impregnated with carbonanotubes was carried out. The initial functionalization of the polymer yielded an ion exchange capacity (IEC) of 4.04, 7.82, 11.1 and 15.53 mmol/g with their corresponding degrees of sulphonation (DS) of 10.93, 21.1, 30.03 and 42.02 %, respectively. The later but highest DS achieved water uptake of 49.23 wt % and proton conductivities of 4.3 x 10-3, 1.2 x 10-3 and 2.6 x 10-2 S/cm for membrane of thickness 250, 215 and 120 mm, respectively. The performance testing of the membrane in a single fuel cell achieved an open circuit voltage (OCV) of 647.23 mV with the synthesised membrane of 35 wt % catalyst loading, 589.79 mV and 410.48 mV of 25 wt % and 15 wt % catalyst loading, respectively at constant DS (42.02 %). Their corresponding power densities achieved were 68.67, 49.20 and 35.83 Mw/cm2, respectively. Thus the functionalization of polyisoprene impregnated with carbon nanotubes through the process of sulphonation with chlorosulphonic acid resulted into the development of solid polymer electrolyte membrane for fuel cell application.

Falling film reactors (FFR) are widely used in industry, mainly in those processes which require an efficient heat exchange. Although, these devices have been studied for several years, there is not yet a full understanding of their behavior. This is due to the fact that the performance of the FFRs can be easily influenced by hydrodynamic factors which affect transport phenomena in the reactor. In this study, an experimental analysis of hydrodynamic factors influencing a FFR is presented, paying special attention to hydrodynamic phenomena such as the phases’ flow regimens and the residence time for the sulphonation of methyl ester (ME) from palm oil with SO3. The results show that along with the SO3/ME ratio the hydrodynamic of both phases (gas and liquid) present in the reactor have a strong influence over the sulphonation efficiency

Falling film reactors (FFR) are widely used in industry, mainly in those processes which require an efficient heat exchange. Although, these devices have been studied for several years, there is not yet a full understanding of their behavior. This is due to the fact that the performance of the FFRs can be easily influenced by hydrodynamic factors which affect transport phenomena in the reactor. In this study, an experimental analysis of hydrodynamic factors influencing a FFR is presented, paying special attention to hydrodynamic phenomena such as the phases' flow regimens and the residence time for the sulphonation of methyl ester (ME) from palm oil with SO3. The results show that along with the SO3/ME ratio the hydrodynamic of both phases (gas and liquid) present in the reactor have a strong influence over the sulphonation efficiency, Los reactores de película descendente (FFR por sus siglas en ingles), son dispositivos ampliamente usados en la industria, principalmente en aquellos procesos que requieren una eficiente transferencia de calor. A pesar que los FFR han sido estudiados por varios años, aun no se ha llegado a una comprensión completa de los procesos que suceden en el reactor. Esto se debe principalmente a factores hidrodinámicos, los cuales afectan los fenómenos de transferencia a lo largo del proceso. En este estudio se presenta un análisis experimental de la influencia de factores hidrodinámicos en un reactor de película descendente, analizando principalmente los fenómenos hidrodinámicos tales como los regímenes de flujo en las fases involucradas y tiempos medios de residencia, para la sulfonación de ésteres metílicos derivados de estearina hidrogenada de palma con SO3. Los resultados mostraron que el comportamiento hidrodinámico en el reactor influencia fuertemente la eficiencia del proceso de sulfonación al mismo nivel que la relación molar SO3/ME

Falling film reactors (FFR) are widely used in industry, mainly in those processes which require an efficient heat exchange. Although, these devices have been studied for several years, there is not yet a full understanding of their behavior. This is due to the fact that the performance of the FFRs can be easily influenced by hydrodynamic factors which affect transport phenomena in the reactor. In this study, an experimental analysis of hydrodynamic factors influencing a FFR is presented, paying special attention to hydrodynamic phenomena such as the phases’ flow regimens and the residence time for the sulphonation of methyl ester (ME) from palm oil with SO3. The results show that along with the SO3/ME ratio the hydrodynamic of both phases (gas and liquid) present in the reactor have a strong influence over the sulphonation efficiency

Falling film reactors (FFR) are widely used in industry, mainly in those processes which require an efficient heat exchange. Although, these devices have been studied for several years, there is not yet a full understanding of their behavior. This is due to the fact that the performance of the FFRs can be easily influenced by hydrodynamic factors which affect transport phenomena in the reactor. In this study, an experimental analysis of hydrodynamic factors influencing a FFR is presented, paying special attention to hydrodynamic phenomena such as the phases' flow regimens and the residence time for the sulphonation of methyl ester (ME) from palm oil with SO3. The results show that along with the SO3/ME ratio the hydrodynamic of both phases (gas and liquid) present in the reactor have a strong influence over the sulphonation efficiency, Los reactores de película descendente (FFR por sus siglas en ingles), son dispositivos ampliamente usados en la industria, principalmente en aquellos procesos que requieren una eficiente transferencia de calor. A pesar que los FFR han sido estudiados por varios años, aun no se ha llegado a una comprensión completa de los procesos que suceden en el reactor. Esto se debe principalmente a factores hidrodinámicos, los cuales afectan los fenómenos de transferencia a lo largo del proceso. En este estudio se presenta un análisis experimental de la influencia de factores hidrodinámicos en un reactor de película descendente, analizando principalmente los fenómenos hidrodinámicos tales como los regímenes de flujo en las fases involucradas y tiempos medios de residencia, para la sulfonación de ésteres metílicos derivados de estearina hidrogenada de palma con SO3. Los resultados mostraron que el comportamiento hidrodinámico en el reactor influencia fuertemente la eficiencia del proceso de sulfonación al mismo nivel que la relación molar SO3/ME

Falling film reactors (FFR) are widely used in industry, mainly in those processes which require an efficient heat exchange. Although, these devices have been studied for several years, there is not yet a full understanding of their behavior. This is due to the fact that the performance of the FFRs can be easily influenced by hydrodynamic factors which affect transport phenomena in the reactor. In this study, an experimental analysis of hydrodynamic factors influencing a FFR is presented, paying special attention to hydrodynamic phenomena such as the phases' flow regimens and the residence time for the sulphonation of methyl ester (ME) from palm oil with SO3. The results show that along with the SO3/ME ratio the hydrodynamic of both phases (gas and liquid) present in the reactor have a strong influence over the sulphonation efficiency, Los reactores de película descendente (FFR por sus siglas en ingles), son dispositivos ampliamente usados en la industria, principalmente en aquellos procesos que requieren una eficiente transferencia de calor. A pesar que los FFR han sido estudiados por varios años, aun no se ha llegado a una comprensión completa de los procesos que suceden en el reactor. Esto se debe principalmente a factores hidrodinámicos, los cuales afectan los fenómenos de transferencia a lo largo del proceso. En este estudio se presenta un análisis experimental de la influencia de factores hidrodinámicos en un reactor de película descendente, analizando principalmente los fenómenos hidrodinámicos tales como los regímenes de flujo en las fases involucradas y tiempos medios de residencia, para la sulfonación de ésteres metílicos derivados de estearina hidrogenada de palma con SO3. Los resultados mostraron que el comportamiento hidrodinámico en el reactor influencia fuertemente la eficiencia del proceso de sulfonación al mismo nivel que la relación molar SO3/ME

A set of experiments was carried out for validating a 40 cm long and ½ inch diameter sulphonation falling film reactor for the sulphonation of hydrogenated palm stearine-derived dodecylbenzene (DDB) and methyl esters (ME) compared to oleumderived gaseous SO3. Volumetric titration was used for determining the percentages of sulphonated (active) matter, sulphuric acid content and unsulphonated oil by petroleum ether extraction. The reactor's functionality was tested in the conditions reported by Gutiérrez et al., for DDB sulphonation. The falling film reactor analysis techniques applied to sulphonated DDB in the scale bank reactor were thus validated in Universidad Nacional de Colombia's Chemical Engineering Department Laboratory with the involvement of the Química Básica Colombiana Company (LIQ, Caloto, Cauca, Colombia). The influence of different process variables on the sulphonation of a mixture of methyl esters was then evaluated. The results obtained in the sulphonator were adjusted to empirical equations using multiple linear regression; these expressions showed the direct effect on sulphonation of variables such as SO3/ME molar ratio, SO3 concentration in gas flow and ME mass flow., Se realizó un conjunto de experimentos de sulfonación de dodecilbenceno (DDB) y ésteres metílicos (ME) derivados de la estearina hidrogenada de palma, con SO3 gaseoso desorbido del óleum, en un reactor de sulfonación en película líquida descendente a escala banco de 40 cm de longitud y ½ pulgada de diámetro interno. Mediante titulaciones volumétricas se determinaron los porcentajes de materia sulfonada y contenido de ácido sulfúrico, así como el porcentaje de aceite libre mediante extracciones con éter de petróleo. La funcionalidad del reactor se verificó efectuando ensayos a condiciones reportadas por Gutiérrez y colaboradores para dodecilbenceno sulfonado (DDBS), para lo cual fueron determinadas las técnicas de análisis en el Laboratorio de Ingeniería Química (LIQ) de la Universidad Nacional de Colombia, sede Bogotá, con el acompañamiento de la empresa Química Básica Colombiana (Caloto, Cauca). Finalmente, se procedió a evaluar la influencia de diferentes variables de proceso sobre la sulfonación de la mezcla de ésteres metílicos. Los resultados obtenidos en el sulfonador se ajustaron por regresión lineal múltiple a ecuaciones empíricas, obteniendo expresiones que muestran de forma directa el efecto de variables como la relación molar SO3/ME, concentración de SO3 en la corriente gaseosa y flujo másico de ME.

Dynamic Fourier Transform Infra-Red (FT-IR) spectroscopy was used to examine the effect of a low sulphonation treatment on the ultrastructure of the primary cell wall of spruce wood. Sheets made from enriched primary cell wall material coming from a low sulphonated thermomechanical pulp were used for studying the viscoelastic response of the polymers using dynamic FT-IR spectroscopy. The overall ultrastructure of the primary cell wall remained largely unaltered, due to the exceptionally low degree of sulphonation used. However, an increased softening of the material as well as a weakening of the lignin,pectin, lignin, protein and pectin, protein interactions were observed. The suggestion is that, together with a structural modification of the lignin, it is the increased viscoelasticity of the material, resulting from the breaking down of the interactions among the polymers, that is the cause for the lower energy demand, when refining correspondingly low sulphonated chips., QC 20101123 Uppdaterad från accepted till published (20101123).