• Energy Research

AbstractThis study provides a new emphasis for research on the valorization of biowastes into nanocatalyst and biorefineries to be integrated with petroleum bioupgrading and polluted water treatment. The response surface optimized batch transesterification of waste‐frying oil using methanol and sustainable animal bone valorized fluorapatite nanocatalyst (FAP) yielded approximately 97% biodiesel via a pseudo‐second‐order reaction with an efficient rate of 0.48 (mol L−1)−1min−1 and activation energy of 13.11 kJ mol−1. In a pioneering step, by‐products of the starch industry and the biodiesel transesterification process; corn‐steep liquor (CSL 0.2 g L−1) and bioglycerol (6.24 g L−1) as nitrogen and carbon sources, increased the dibenzothiophene biodesulfurization (BDS) efficiency of a novel biodesulfurizing Rhodococcus jialingiae strain HN3 (NCBI Gene Bank Accession No. MN173539) sixfold. Further, upon the application of such bioproducts in a batch BDS process (1/3 petro‐diesel/water) of 96 h; HN3 desulfurized 82.26% of 0.62 wt.% sulfur without affecting the petro‐diesel calorific value. In an attempt to reach zero waste, an auxiliary pioneering step was performed, where the spent waste FAP, after being efficiently used for four successive transesterification cycles, was applied to photo‐remediate 4‐nitrophenol polluted water under UV‐irradiation. Advantageously, the fresh and spent waste FAP recorded the same photodegradation capabilities. Where they obeyed the Langmuir–Hinshelwood kinetic model (R2 ≥ 0.966) recording the same rate constants (kapp 0.032 min−1) and were efficiently reused for four successive polluted‐water treatment cycles. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

La transestérification non catalytique a été reconnue comme une technique efficace pour la production de biodiesel. Il présente de nombreux avantages par rapport à la transestérification catalytique classique, où il élimine les difficultés de préparation et de séparation des catalyseurs. Il produit également un rendement élevé en biodiesel en un temps de réaction plus court. Cependant, il nécessite des conditions de fonctionnement difficiles à température et pression de réaction élevées, en plus d'utiliser un large excès de méthanol. Dans le but d'atténuer ces problèmes, une conception/intégration de processus pour la production de biodiesel a été réalisée. Le processus a été soumis à une intégration de masse et d'énergie pour minimiser les besoins en méthanol frais et pour minimiser les énergies de chauffage et de refroidissement, respectivement. Une nouvelle méthode graphique d'analyse de pincement a été utilisée pour évaluer la performance énergétique d'une conception de la littérature pour le processus actuel. Il a ensuite été utilisé pour développer un réseau d'échangeurs de chaleur optimal (HEN) pour le processus en faisant correspondre les flux de processus. En outre, la conception réalisée à l'aide d'une simulation commerciale automatisée (Aspen Energy Analyzer) a été évaluée à l'aide de la même méthode graphique. La conception de la POULE produite à partir de la méthode graphique a atteint les résultats optimaux par rapport aux objectifs énergétiques. La transesterificación no catalítica ha sido reconocida como una técnica eficaz para la producción de biodiésel. Tiene muchas ventajas sobre la transesterificación catalítica convencional, donde elimina las dificultades de preparación y separación de los catalizadores. También produce un alto rendimiento de biodiesel en un tiempo de reacción más corto. Sin embargo, requiere condiciones de operación duras a alta temperatura y presión de reacción, además de usar un gran exceso de metanol. En un intento por mitigar estos problemas, se ha realizado un proceso de diseño/integración para la producción de biodiesel. El proceso se ha sometido a integración de masa y energía para minimizar los requisitos de metanol fresco y para minimizar las energías de calefacción y refrigeración, respectivamente. Se ha utilizado un nuevo método gráfico de análisis de pellizcos para evaluar el rendimiento energético de un diseño de literatura para el proceso actual. Posteriormente, se ha utilizado para desarrollar una red de intercambiadores de calor (HEN) óptima para el proceso mediante el emparejamiento de las corrientes del proceso. Además, el diseño realizado mediante el uso de una simulación comercial automatizada (Aspen Energy Analyzer) se ha evaluado utilizando el mismo método gráfico. El diseño de GALLINA producido a partir del método gráfico ha logrado los resultados óptimos con respecto a los objetivos energéticos. Non-catalytic transesterification has been recognised as an effective technique for biodiesel production. It has many advantages over conventional catalytic transesterification, where it eliminates the difficulties of catalysts preparation and separation. It also produces high biodiesel yield in shorter reaction time. However, it requires harsh operating conditions at high reaction temperature and pressure, in addition to using large excess of methanol. In an attempt to mitigate these problems, a process design/integration for biodiesel production has been performed. The process has been subjected to both mass and energy integration to minimise fresh methanol requirements and to minimise heating and cooling energies, respectively. A new graphical Pinch Analysis method has been used to evaluate the energy performance of a literature design for the current process. It has been subsequently used to develop an optimum heat exchanger network (HEN) for the process by matching of process streams. Also, the design made by using an automated commercial simulation (Aspen Energy Analyzer) has been evaluated using the same graphical method. The produced HEN design from graphical method has achieved the optimum results with respect to energy targets. تم التعرف على التحويل غير التحفيزي كأسلوب فعال لإنتاج الديزل الحيوي. له العديد من المزايا على التحويل التحفيزي التقليدي، حيث يزيل صعوبات تحضير المحفزات وفصلها. كما أنه ينتج عائدًا مرتفعًا من الديزل الحيوي في وقت تفاعل أقصر. ومع ذلك، فإنه يتطلب ظروف تشغيل قاسية عند درجة حرارة وضغط تفاعل عاليين، بالإضافة إلى استخدام فائض كبير من الميثانول. في محاولة للتخفيف من هذه المشاكل، تم تنفيذ تصميم/تكامل عملية لإنتاج الديزل الحيوي. تم إخضاع العملية لكل من تكامل الكتلة والطاقة لتقليل متطلبات الميثانول الطازج وتقليل طاقات التسخين والتبريد، على التوالي. تم استخدام طريقة تحليل قرصة رسومية جديدة لتقييم أداء الطاقة لتصميم الأدبيات للعملية الحالية. تم استخدامه لاحقًا لتطوير شبكة مبادل حراري مثالية (HEN) للعملية من خلال مطابقة تدفقات العملية. كما تم تقييم التصميم الذي تم باستخدام محاكاة تجارية آلية (Aspen Energy Analyzer) باستخدام نفس الطريقة الرسومية. حقق تصميم الدجاجة المنتج من الطريقة الرسومية النتائج المثلى فيما يتعلق بأهداف الطاقة.

Biodiesel production using supercritical methanolysis has received immense interest over the last few years. It has the ability to convert high acid value feedstock into biodiesel using a single-pot reaction. However, the energy intensive process is the main disadvantage of supercritical biodiesel process. Herein, a conceptual design for the integration of supercritical biodiesel process with organic Rankine cycle (ORC) is presented to recover residual hot streams and to generate electric power. This article provides energy and techno-economic comparative study for three developed scenarios as follows: original process with no energy integration (Scenario 1), energy integrated process (Scenario 2) and advanced energy integrated process with ORC (Scenario 3). The developed integrated biodiesel process with ORC resulted in electric power generation that has not only satisfied the process electric requirement but also provided excess power of 257 kW for 8,000 tonnes/annum biodiesel plant. The techno-economic comparative analysis resulted in favouring the third scenario with 36% increase in the process profitability than the second scenario. Sensitivity analysis has shown that biodiesel price variation has significant effect on the process profitability. In summary, integrating supercritical biodiesel production process with ORC appears to be a promising approach for enhancing the process techno-economic profitability and viability.

Pyrolysis process has been considered to be an efficient approach for valorization of lignocellulosic biomass into bio-oil and value-added chemicals. Bio-oil refers to biomass pyrolysis liquid, which contains alkanes, aromatic compounds, phenol derivatives, and small amounts of ketone, ester, ether, amine, and alcohol. Lignocellulosic biomass is a renewable and sustainable energy resource for carbon that is readily available in the environment. This review article provides an outline of the pyrolysis process including pretreatment of biomass, pyrolysis mechanism, and process products upgrading. The pretreatment processes for biomass are reviewed including physical and chemical processes. In addition, the gaps in research and recommendations for improving the pretreatment processes are highlighted. Furthermore, the effect of feedstock characterization, operating parameters, and types of biomass on the performance of the pyrolysis process are explained. Recent progress in the identification of the mechanism of the pyrolysis process is addressed with some recommendations for future work. In addition, the article critically provides insight into process upgrading via several approaches specifically using catalytic upgrading. In spite of the current catalytic achievements of catalytic pyrolysis for providing high-quality bio-oil, the production yield has simultaneously dropped. This article explains the current drawbacks of catalytic approaches while suggesting alternative methodologies that could possibly improve the deoxygenation of bio-oil while maintaining high production yield.

Conventional biodiesel manufacturing uses alcohol as an acyl acceptor, resulting in glycerol as a side product. The increased demand for biodiesel has led to the production of a substantial surplus of glycerol, exceeding the market need. Consequently, glycerol is now being regarded as a byproduct, and in some cases, even as waste. The present study aims to suggest an economically viable and ecologically friendly approach for maintaining the viability of the biodiesel sector. This involves generating an alternative byproduct of higher value, rather than glycerol. Triacetin is produced through the interesterification of triglycerides with methyl acetate, and is a beneficial ingredient to biodiesel, reducing the need for extensive product separation. The primary objective of this research is to improve the interesterification reaction by optimising process parameters to maximise biodiesel production while using sulphuric acid as an economically viable catalyst. The study utilised the Box–Behnken design (BBD) to investigate the influence of various process variables on biodiesel yield, such as reaction time, methyl acetate to oil molar ratio, and catalyst concentration. An optimisation study using Response Surface Methodology (RSM) focused on key process reaction parameters, including the methyl acetate to oil (MA:O) molar ratio, catalyst concentration, and residence time. The best conditions produced a biodiesel blend with a 142% yield at a 12:1 MA:O molar ratio, with 0.1 wt% of catalyst loading within 1.7 h. The established technique is deemed to be undeniably effective, resulting in an efficient biodiesel production process.

In this study, valorisation of high acid value waste cooking oil into biodiesel has been investigated. Non-catalytic transesterification using supercritical methanol has been used for biodiesel production. Four controllable independent process variables have been considered for analysis including methanol to oil (M:O) molar ratio, temperature, pressure and time. Uncommon effects of process variables on the reaction responses, e.g. biodiesel and glycerol yields, have been observed and extensively discussed. Response surface methodology (RSM) via Central Composite Design (CCD) has been used to analyse the effect of the process variables and their interactions on the reaction responses. A quadratic model for each response has been developed representing the interrelationships between process variables and responses. Analysis of Variance (ANOVA) has been used to verify the significance effect of each process variable and their interactions on reaction responses. Optimal reaction conditions have been predicted using RSM for 98% and 2.05% of biodiesel and glycerol yields, respectively at 25:1 M:O molar ratio, 265oC temperature, 110 bar pressure and 20 minutes reaction time. The predicted optimal conditions have been validated experimentally resulting in 98.82% biodiesel yield, representing 0.83% relative error. The quality of the produced biodiesel showed excellent agreement with the European biodiesel standard (EN14214).

© 2019 The synthesis of butylene carbonate (BC) through the reaction of butylene oxide (BO) and carbon dioxide (CO 2 ) has been investigated using highly efficient graphene-inorganic heterogeneous catalyst, cerium-lanthana-zirconia and graphene oxide represented as Ce–La–Zr–GO nanocomposite. The systematic multivariate optimisation of BC synthesis via CO 2 utilisation using graphene-inorganic nanocomposite has been developed using Box-Behnken Design (BBD) of Response Surface Methodology (RSM). The BBD has been applied to optimise the single and interactive effect of four independent reaction variables, i.e. reaction temperature, pressure, catalyst loading and reaction time on the conversion of BO and BC yield. Two quadratic regression models have been developed representing an empirical relationship between each reaction response and all the independent variables. The predicted models have been validated statistically and experimentally, where a high agreement has been observed between predicted and experimental results with approximate relative errors of ±1.45% and ±1.52% for both the BO conversion and BC yield, respectively. The implementation of RSM optimisation process for the conversion of BC through the reaction between BO and CO 2 , has offered a new direction in green chemical process in terms of waste reduction, maximising production of value-added chemicals and effectively utilise CO 2 gas emissions.

Biodiesel has been established as a promising alternative fuel to petroleum diesel. This study offers a promising energy conversion platform to valorise high acidity waste cooking oil (WCO) into biodiesel in a single-step reaction via supercritical methanol. Carbon dioxide (CO2) has been used as a co-solvent in the reaction with a catalytic effect to enhance the production of biodiesel. This work provides an in-depth assessment of the yield of four fatty acids methyl esters (FAME) from their correspondent triglycerides and fatty acids. The effects of four independent process variables, i.e., methanol to oil (M:O) molar ratio, temperature, pressure, and time, have been investigated using Response Surface Methodology (RSM). Four quadratic models have been developed between process variables and the yield of FAMEs. The statistical validation of the predicted models has been performed using analysis of variance (ANOVA). Numerical optimisation has been employed to predict the optimal conditions for biodiesel production. The predicted optimal conditions are at 25:1 M:O molar ratio, 254.7 °C, 110 bar within 17 min resulting in 99.2%, 99.3%, 99.13%, and 99.05% of methyl-oleate, methyl-palmitate, methyl-linoleate, and methyl-stearate yields, respectively. The predicted optimum conditions have been validated experimentally.