Publications by authors named "Janusz A Kozinski"

Hydrothermal flames are formed in supercritical water in the presence of a fuel and an oxidant (usually air or oxygen). Integrating hydrothermal flames as the heat source for supercritical water oxidation helps to minimize the reaction time (to milliseconds), improve the reaction kinetics and reduce the chances of corrosion and reactor plugging. This review outlines state-of-the-art research on hydrothermal flames including the impacts of process parameters on flame ignition.

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Forest fires significantly affect the wildlife, vegetation, composition and structure of the forests. This study explores the potential of partially burnt wood recovered in the aftermath of a recent Canadian forest fire incident as a feedstock for generating hydrogen-rich syngas through hydrothermal gasification. Partially burnt wood was gasified in hydrothermal conditions to study the influence of process temperature (300-500 °C), residence time (15-45 min), feed concentration (10-20 wt%) and biomass particle size (0.

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This paper proposes a conceptual design for the catalytic supercritical water gasification of soybean straw. The design consists of four process units for pretreatment, gasification, separation, purification and combustion. The economic feasibility of hydrogen production was evaluated based on a comprehensive cash flow analysis.

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Apprehensions relating to global warming, climate change, pollution, rising energy demands as well as fluctuating crude oil prices and supply are leading to a shift in global interest to find suitable alternatives to fossil fuels. This review aims to highlight the many different facets of butanol as an advanced next-generation transportation biofuel. Butanol has fuel properties almost on a par with gasoline, such as high energy content, low vapor pressure, non-hygroscopic nature, less volatility, flexible fuel blends and high octane number.

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A microfluidic flow lithography approach was investigated to synthesize highly porous nonspherical particles and Janus particles in a one-step and high-throughput fashion. In this study, using common solvents as porogens, we were able to synthesize highly porous particles with different shapes using ultraviolet (UV) polymerization-induced phase separation in a microfluidic channel. We also studied the pore-forming process using operating parameters such as porogen type, porogen concentration, and UV intensity to tune the pore size and increase the pore size to submicron levels.

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Surface wrinkled particles are ubiquitous in nature and present in different sizes and shapes, such as plant pollens and peppercorn seeds. These natural wrinkles provide the particles with advanced functions to survive and thrive in nature. In this work, by combining flow lithography and plasma treatment, we have developed a simple method that can rapidly create wrinkled non-spherical particles, mimicking the surface textures in nature.

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The organic wastes such as lignocellulosic biomass, municipal solid waste, sewage sludge and livestock manure have attracted attention as alternative sources of energy. Cattle manure, a waste generated in surplus amounts from the feedlot, has always been a chief environmental concern. This study is focused on identifying the candidacy of horse manure as a next generation feedstock for biofuel production through supercritical water gasification.

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Poly(dimethylsiloxane) (PDMS)-based microfluidics provide a novel approach to advanced material synthesis. While PDMS has been successfully used in a wide range of industrial applications, due to the weak mechanical property channels generally possess low aspect ratios (AR) and thus produce microparticles with similarly low ARs. By increasing the channel width to nearly 1 cm, AR to 267, and implementing flow lithography, we were able to establish the slit-channel lithography.

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Chitosan-glutaraldehyde copolymer sorbents were synthesized by reacting variable weight ratios (low, medium, and high) of glutaraldehyde with fixed amounts of chitosan. Two commercially available chitosan polymers with low (L) and high (H) relative molecular weights were investigated. The chitosan-glutaraldehyde (Chi-Glu) copolymer sorbents are denoted as CPL-X or CPH-X where X denotes the incremental level (X=-1, -2, -3) of glutaraldehyde.

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β-Cyclodextrin-chitosan-glutaraldehyde terpolymers were synthesized by reacting variable weight fractions of β-cyclodextrin (β-CD) and chitosan (Chi), with a constant amount of crosslinker (glutaraldehyde). The β-CD:Chi:Glu terpolymer sorbents were characterized by FT-IR spectroscopy and TGA. The solid-solution sorption isotherms in aqueous solution for the copolymers were characterized using two spectroscopic methods (UV-Vis and ICAP-OES) for p-nitrophenol (PNP) and the arsenate oxoanion (HAsO(4)(2-)) at alkaline pH conditions.

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The level of protection of a building against the intentional or accidental release of chemical agents is crucial. Both scenarios could endanger life and safety of the buildings occupants. Equipping buildings with appropriate chemical sensors can alert the building occupants about the contaminant release.

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The sorption capacity parameters obtained for batch studies provide useful information about biosorption system. However, such data fail to explain the process under continuous-flow conditions. The present study is an attempt to explore the biosorption of Pb(II) and Cr(III) by straw from local wheat (Triticum aestivum).

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Conventional technologies for the removal/remediation of toxic metal ions from wastewaters are proving expensive due to non-regenerable materials used and high costs. Biosorption is emerging as a technique offering the use of economical alternate biological materials for the purpose. Functional groups like carboxyl, hydroxyl, sulphydryl and amido present in these biomaterials, make it possible for them to attach metal ions from waters.

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Decomposition of organosolve lignin in water/phenol solutions was studied in a 50 nL micro-reactor coupled with optical, Raman and infrared microscopies at temperatures up to 600 degrees C and water densities up to 1165 kg/m3. It was found that when phenol was used with {lignin+water} mixtures that a homogenous phase was formed that seemed to promote the decomposition of lignin into phenolic fragments by hydrolysis and pyrolysis. Phenol, along with the homogenous reaction conditions also inhibited re-polymerization of the phenolics and promoted oil formation.

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A new methodology was developed using a Thermo-Gravi-metric Furnace coupled to a Fourier Transform Infrared Spectrometer (TGF-FTIR) to study the low temperature treatment of waste lubricating oils. The sample was heated from room temperature to a final temperature of 1,000 °C at an initial heating rate of 3 °C/min, to slow down the oxidative pyrolysis process allowing for the events taking place to be observable. It was found that the majority of the process in terms of weight loss and gas-phase evolution was over by 650 °C, and thus, the remainder of the sample heating was accomplished at a rate of 5 °C/min.

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