Mohammad Reza Rahimpour

Bio: Mohammad Reza Rahimpour is an academic researcher from Shiraz University. The author has contributed to research in topics: Hydrogen production & Hydrogen. The author has an hindex of 49, co-authored 493 publications receiving 10790 citations. Previous affiliations of Mohammad Reza Rahimpour include University of Newcastle & Shahed University.

Upgrading of lignin-derived bio-oils by catalytic hydrodeoxygenation

Abstract: The incentive for use of renewable resources to replace fossil sources is motivating extensive research on new and alternative fuels derived from biomass. Bio-oils derived from cellulosic biomass offer the prospect of becoming a major feedstock for production of fuels and chemicals, and lignin is a plentiful, underutilized component of cellulosic biomass. Lignin conversion requires depolymerization and removal of oxygen. Likely processes for lignin conversion involve depolymerization (e.g., by pyrolysis) and catalytic upgrading of the resultant bio-oils. A major goal of the upgrading is catalytic hydrodeoxygenation (HDO), which involves reactions with hydrogen that produce hydrocarbons and water. The aim of this review is to present a critical introduction to HDO chemistry focused on compounds derived from lignin, including a summary of HDO reactions and those that accompany them, with a comparison of catalysts addressing their activities, selectivities, and stabilities. The reactions are evaluated in terms of reaction pathways of compounds representative of lignin-derived bio-oils, including anisole, guaiacol, and phenol. The review includes recommendations for further research and an attempt to place HDO in a context of options for renewable fuels and chemicals, but it does not provide an economic assessment.

Hydrogenation of CO2 to value-added products—A review and potential future developments

Abstract: Fossil fuel depletion, global warming, climate change, and steep hikes in the price of fuels are driving scientists to investigate on commercial and environmentally friendly fuels. The process of CO2 conversion to value-added products has been considered as a possible remedy to fulfill the requirements. The present review paper comprehensively discusses two different processes, namely hydrocarbon and methanol synthesis which are extensively used to convert CO2 to value-added products. Reaction mechanisms as well as the effects of catalyst, reactor type and operating conditions on product efficiency enhancement of each process are reviewed. Furthermore a brief overview on the reactor types as the most effective component of the theoretical and experimental reported results on the process improvement is given. All the information is tabulated in order to make the gathered information easily conclusive. Finally, by taking the available information into account the best reactor configuration which is adjustable to reaction mechanism is proposed.

Dimethyl ether: A review of technologies and production challenges

Abstract: Dimethyl ether (DME) is a well-known propellant and coolant, an alternative clean fuel for diesel engines which simultaneously is capable of achieving high performance and low emission of CO, NOx and particulates in its combustion. It can be produced from a variety of feed-stocks such as natural gas, coal or biomass; and also can be processed into valuable co-products such as hydrogen as a sustainable future energy. This review, which also can be counted as an extensive, pioneer review paper on this topic, presents recent developments in synthesis methods of dimethyl ether as an alternative energy while focuses on conventional processes and innovative technologies in reactor design and employed catalysts. In this context, synthesis methods are classified according to their use of raw material type as direct and indirect methods as well as other routes, since different methods need their own operating condition. Also, the available data for the selectivity to DME and its yield as a function of H2/CO and CO2 content of the feed is discussed.

Palladium membranes applications in reaction systems for hydrogen separation and purification: A review

Abstract: Application of palladium-based membrane technology in chemical reactions is currently focused on producing ultrapure hydrogen. Due to the environmental concerns and undesirable side effects of greenhouse gases, hydrogen has great potential as an alternative future fuel. Pd-alloy membranes have demonstrated tremendous potential for the hydrogen extraction in hydrogen-dependent reactions. Numerous studies have been done investigating the diffusion of hydrogen through palladium membranes. In this review, the ability of Pd-alloy membrane reactors in the removal of hydrogen from water gas shift, steam reforming, and dehydrogenation reactions is evaluated. This review is divided into several sections including palladium membranes, Pd-alloy membranes, composite Pd-based membranes, and their preparation methods Moreover, the hydrogen permeation rate, Sieverts’ law, Damkohler-Peclet product design parameter, and various membrane reactors will be discussed in detail. There is also an overview of the last-decade researches on Pd-based membrane reactors. Finally, some essential ideas for the improvement of future membrane technology are proposed.

Kirk-Othmer Encyclopedia of Chemical Technology数据库介绍及实例

Abstract: 介绍了Kirk—Othmer Encyclopedia of Chemical Technology（化工技术百科全书）（第五版）电子图书网络版数据库，并对该数据库使用方法和检索途径作出了说明，且结合实例简单地介绍了该数据库的检索方法。

Recent advances in catalytic hydrogenation of carbon dioxide

Abstract: Owing to the increasing emissions of carbon dioxide (CO2), human life and the ecological environment have been affected by global warming and climate changes. To mitigate the concentration of CO2 in the atmosphere various strategies have been implemented such as separation, storage, and utilization of CO2. Although it has been explored for many years, hydrogenation reaction, an important representative among chemical conversions of CO2, offers challenging opportunities for sustainable development in energy and the environment. Indeed, the hydrogenation of CO2 not only reduces the increasing CO2 buildup but also produces fuels and chemicals. In this critical review we discuss recent developments in this area, with emphases on catalytic reactivity, reactor innovation, and reaction mechanism. We also provide an overview regarding the challenges and opportunities for future research in the field (319 references).

Catalytic Transformation of Lignin for the Production of Chemicals and Fuels

Abstract: and Fuels Changzhi Li,† Xiaochen Zhao,† Aiqin Wang,† George W. Huber,†,‡ and Tao Zhang*,† †State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China ‡Department of Chemical and Biological Engineering, University of WisconsinMadison, Madison, Wisconsin 53706, United States

Chemicals from lignin: an interplay of lignocellulose fractionation, depolymerisation, and upgrading

Abstract: In pursuit of more sustainable and competitive biorefineries, the effective valorisation of lignin is key. An alluring opportunity is the exploitation of lignin as a resource for chemicals. Three technological biorefinery aspects will determine the realisation of a successful lignin-to-chemicals valorisation chain, namely (i) lignocellulose fractionation, (ii) lignin depolymerisation, and (iii) upgrading towards targeted chemicals. This review provides a summary and perspective of the extensive research that has been devoted to each of these three interconnected biorefinery aspects, ranging from industrially well-established techniques to the latest cutting edge innovations. To navigate the reader through the overwhelming collection of literature on each topic, distinct strategies/topics were delineated and summarised in comprehensive overview figures. Upon closer inspection, conceptual principles arise that rationalise the success of certain methodologies, and more importantly, can guide future research to further expand the portfolio of promising technologies. When targeting chemicals, a key objective during the fractionation and depolymerisation stage is to minimise lignin condensation (i.e. formation of resistive carbon–carbon linkages). During fractionation, this can be achieved by either (i) preserving the (native) lignin structure or (ii) by tolerating depolymerisation of the lignin polymer but preventing condensation through chemical quenching or physical removal of reactive intermediates. The latter strategy is also commonly applied in the lignin depolymerisation stage, while an alternative approach is to augment the relative rate of depolymerisation vs. condensation by enhancing the reactivity of the lignin structure towards depolymerisation. Finally, because depolymerised lignins often consist of a complex mixture of various compounds, upgrading of the raw product mixture through convergent transformations embodies a promising approach to decrease the complexity. This particular upgrading approach is termed funneling, and includes both chemocatalytic and biological strategies.