There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

https://www.massey.ac.nz/~ychisti/Biodiesel.pdf

Biodiesel from microalgae.

Fast pyrolysis utilizes biomass to produce a product that is used both as an energy source and a feedstock for chemical production. Considerable efforts have been made to convert wood biomass to liquid fuels and chemicals since the oil crisis in mid-1970s. This review focuses on the recent developments in the wood pyrolysis and reports the characteristics of the resulting bio-oils, which are the main products of fast wood pyrolysis. Virtually any form of biomass can be considered for fast pyrolysis. Most work has been performed on wood, because of its consistency and comparability between tests. However, nearly 100 types of biomass have been tested, ranging from agricultural wastes such as straw, olive pits, and nut shells to energy crops such as miscanthus and sorghum. Forestry wastes such as bark and thinnings and other solid wastes, including sewage sludge and leather wastes, have also been studied. In this review, the main (although not exclusive) emphasis has been given to wood. The literature on woo...

Pyrolysis of Wood/Biomass for Bio-oil: A Critical Review

Sustainable economic and industrial growth requires safe, sustainable resources of energy. For the future re-arrangement of a sustainable economy to biological raw materials, completely new approaches in research and development, production, and economy are necessary. The ‘first-generation’ biofuels appear unsustainable because of the potential stress that their production places on food commodities. For organic chemicals and materials these needs to follow a biorefinery model under environmentally sustainable conditions. Where these operate at present, their product range is largely limited to simple materials (i.e. cellulose, ethanol, and biofuels). Second generation biorefineries need to build on the need for sustainable chemical products through modern and proven green chemical technologies such as bioprocessing including pyrolysis, Fisher Tropsch, and other catalytic processes in order to make more complex molecules and materials on which a future sustainable society will be based. This review focus on cost effective technologies and the processes to convert biomass into useful liquid biofuels and bioproducts, with particular focus on some biorefinery concepts based on different feedstocks aiming at the integral utilization of these feedstocks for the production of value added chemicals.

http://staff.cimap.res.in/PublicationFiles/Renew_Sustain_Energ_Rev_14_578.pdf

Production of first and second generation biofuels: A comprehensive review

Bitumen-derived gas oils that enter hydrotreaters contain fine solids such as minerals, heavy metals, and coke. The deposition of these fines will eventually restrict the flow and result in pressure buildup across the hydrotreater, which eventually necessitate the premature shutting down of the reactor system. To determine if certain types of fine particles had a greater detriment to the hydrotreating process, a series of experiments were performed by accelerated fine deposition in a trickle bed catalytic reactor under industrial conditions using bitumen-derived light gas oil. Kaolinite, montmorillonite, pyrite, and petroleum coke fines had no significant impact on the catalyst activity and catalyst deactivation toward hydrodenitrogenation (HDN), hydrodesulfurization (HDS), and hydrodearomatization. Unlike the above fines, iron(III)oxide was found to convert into FeS under hydrotreating conditions, which provided a promoting effect for HDN and HDS reactions. When comparing the trends in pressure drop across the catalyst bed, there was a delayed period during the initial fine deposition where no change in pressure drop was observed, followed by an exponential increase in pressure due to the decrease in bed porosity. The difference found between these fines was the length of this delayed period, with iron(III)oxide and petroleum coke having the longest periods of no pressure growth. From inductively coupled plasma, scanning electron microscopy with energy-dispersive spectroscopy, X-ray diffraction, and Brunauer–Emmett–Teller analysis of the fresh and spent catalysts, it was determined that the deposition of all fines occurred within the packing material in the preheating zone, with only petroleum coke and iron(III)oxide fines being found on the surface of the catalysts. 

Ajay K. Dalai

Papers

Impact of Fine Solids on Hydrotreating of Bitumen-Derived Gas Oil

Catalytic processes for clean energy, waste minimization and green chemicals

Hydrothermal and Thermochemical Synthesis of Bio-Oil from Lignocellulosic Biomass: Composition, Engineering and Catalytic Upgrading

Parametric and hydrodynamics studies on gasification performance of biomass pellets in a pilot-scale fluidized bed gasifier

Preface: Green Catalytic Processes: Broad topic: Catalysis for Clean Energy and Environmentally Friendly Chemical Production