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Prof. Dr. Ajay K Dalai
Department of Chemical and Biological Engineering, University of Saskatchewan, Saskatoon, SK Canada S7N 5A9

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0 Biomass
0 Gasification
0 Hydrogenation
0 Hydroprocessing
0 Pyrolysis

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Research article
Published: 16 August 2021 in ACS Omega
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Thermal degradation behavior and kinetics of two agricultural (soy and oat hulls) and two forestry biomass (willow and spruce) residues were investigated using a unique combination of model-fitting and model-free methods. Experiments were carried out in an inert atmosphere at different heating rates. Both single step and multistep models were explored in deriving activation energies, frequency factors, and mechanisms of all four biomass residues. For the single step models, activation energy values ranged from 107.2 kJ/mol for willow and 139.7 kJ/mol for soy hull, and the frequency factors for both materials were 1.1 × 109 and 2.66 × 1012 s–1, respectively. The multistep models gave further insight into the different mechanisms across the full degradation spectrum. There was an observed difference between the number of distinct steps/mechanisms for the agriculture-based versus wood-based biomass materials, with pyrolysis occurring in three distinct steps for the agricultural biomass residues while the woody residues degraded in two steps. The difference in the number of distinct steps can be attributed to the composition and distribution of components of the biomass, which would differ based on the nature and source of the biomass.

ACS Style

Tolu Emiola-Sadiq; Lifeng Zhang; Ajay K. Dalai. Thermal and Kinetic Studies on Biomass Degradation via Thermogravimetric Analysis: A Combination of Model-Fitting and Model-Free Approach. ACS Omega 2021, 1 .

AMA Style

Tolu Emiola-Sadiq, Lifeng Zhang, Ajay K. Dalai. Thermal and Kinetic Studies on Biomass Degradation via Thermogravimetric Analysis: A Combination of Model-Fitting and Model-Free Approach. ACS Omega. 2021; ():1.

Chicago/Turabian Style

Tolu Emiola-Sadiq; Lifeng Zhang; Ajay K. Dalai. 2021. "Thermal and Kinetic Studies on Biomass Degradation via Thermogravimetric Analysis: A Combination of Model-Fitting and Model-Free Approach." ACS Omega , no. : 1.

Review
Published: 04 August 2021 in Environmental Chemistry Letters
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The applications of green chemistry and industrial bioprocessing are becoming more popular to address concerns of pollution, climate change, global warming, circular bioeconomy, sustainable development goals and energy security. Both biological and thermochemical routes can play vital roles in transforming waste lignocellulosic biomass to high-value bioproducts. Lignocellulosic biomass contains essential building blocks that could be tapped to generate biofuels, biochemicals and biomaterials to replace petroleum-derived fuels and chemicals. Besides containing extractives and ash, lignocellulosic feedstocks are made up of cellulose, hemicellulose and lignin typically in the ranges of 35–55 wt%, 20–40 wt% and 10–25 wt%, respectively. Catalytic thermochemical approaches are effective for biomass conversion with a significant yield of various platform chemicals, such as furfural, 5-hydroxymethylfurfural, levulinic acid and other furan or non-furan-based chemicals. These chemicals play a crucial part in the synthesis of different fuel-based materials, which can successfully replace petroleum-based chemicals or fuels. Lignocellulosic biomass and their derived monomeric sugars can be catalytically converted into various platform chemicals using different homogeneous and heterogeneous catalysts. In this review paper, we have highlighted some promising catalysts such as mineral acids, mesoporous silica materials, zeolites, metal–organic frameworks, metal oxides and ionic liquids used in biorefining to generate biochemicals. We have also reviewed a few pieces of notable literature presenting the catalytic conversion of cellulose, hemicellulose, cellobiose, glucose, fructose and xylose into various high-value chemicals.

ACS Style

Falguni Pattnaik; Shreya Tripathi; Biswa R. Patra; Sonil Nanda; Vivek Kumar; Ajay K. Dalai; Satyanarayan Naik. Catalytic conversion of lignocellulosic polysaccharides to commodity biochemicals: a review. Environmental Chemistry Letters 2021, 1 -18.

AMA Style

Falguni Pattnaik, Shreya Tripathi, Biswa R. Patra, Sonil Nanda, Vivek Kumar, Ajay K. Dalai, Satyanarayan Naik. Catalytic conversion of lignocellulosic polysaccharides to commodity biochemicals: a review. Environmental Chemistry Letters. 2021; ():1-18.

Chicago/Turabian Style

Falguni Pattnaik; Shreya Tripathi; Biswa R. Patra; Sonil Nanda; Vivek Kumar; Ajay K. Dalai; Satyanarayan Naik. 2021. "Catalytic conversion of lignocellulosic polysaccharides to commodity biochemicals: a review." Environmental Chemistry Letters , no. : 1-18.

Review
Published: 02 August 2021 in Catalysts
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Recently, due to the escalating usage of non-renewable fossil fuels such as coal, natural gas and petroleum coke in electricity and power generation, and associated issues with pollution and global warming, more attention is being paid to finding alternative renewable fuel sources. Thermochemical and hydrothermal conversion processes have been used to produce biochar and hydrochar, respectively, from waste renewable biomass. Char produced from the thermochemical and hydrothermal decomposition of biomass is considered an environmentally friendly replacement for solid hydrocarbon materials such as coal and petroleum coke. Unlike thermochemically derived biochar, hydrochar has received little attention due to the lack of literature on its production technologies, physicochemical characterization, and applications. This review paper aims to fulfill these objectives and fill the knowledge gaps in the literature relating to hydrochar. Therefore, this review discusses the most recent studies on hydrochar characteristics, reaction mechanisms for char production technology such as hydrothermal carbonization, as well as hydrochar activation and functionalization. In addition, the applications of hydrochar, mainly in the fields of agriculture, pollutant adsorption, catalyst support, bioenergy, carbon sequestration, and electrochemistry are reviewed. With advancements in hydrothermal technologies and other environmentally friendly conversion technologies, hydrochar appears to be an appealing bioresource for a wide variety of energy, environmental, industrial, and commercial applications.

ACS Style

Shima Masoumi; Venu Borugadda; Sonil Nanda; Ajay Dalai. Hydrochar: A Review on Its Production Technologies and Applications. Catalysts 2021, 11, 939 .

AMA Style

Shima Masoumi, Venu Borugadda, Sonil Nanda, Ajay Dalai. Hydrochar: A Review on Its Production Technologies and Applications. Catalysts. 2021; 11 (8):939.

Chicago/Turabian Style

Shima Masoumi; Venu Borugadda; Sonil Nanda; Ajay Dalai. 2021. "Hydrochar: A Review on Its Production Technologies and Applications." Catalysts 11, no. 8: 939.

Journal article
Published: 22 July 2021 in Current Research in Food Science
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Currently, flaxseed oil is used as an important functional food constituent owing to its large content of omega-3 fatty acids. However, flaxseed oil does not contain carotenoids that could enhance the oxidative stability of the oil. In this study, carotenoids extracted from sea buckthorn pomace were used to enrich cold-pressed flaxseed oil via an ultrasound-assisted extraction technique (UAE). The process parameters were optimized through Box-Behnken design to maximize the carotenoid content in the flaxseed oil. The results obtained by statistical analysis indicated that the yield of 14.02 mg/L of carotenoid content was found in the enriched flaxseed oil at 75.6 min, feed to oil ratio of 19.9 (wt. basis), and amplitude 80.81%. Further, UAE at optimum process parameters was compared with the conventional extraction (CE) method, and it was found that UAE had ~ 49 wt% of higher carotenoid content relative to CE. The physicochemical properties of the enriched flaxseed oil were determined to evaluate the effects of carotenoid enrichment in the flaxseed oil. Based on the outcomes of the present investigation, enriched flaxseed oil could be the potential source for the pharmaceuticals and nutraceuticals industry.

ACS Style

Vidhi H. Bhimjiyani; Venu Babu Borugadda; Satyanarayan Naik; Ajay K. Dalai. Enrichment of flaxseed (Linum usitatissimum) oil with carotenoids of sea buckthorn pomace via ultrasound-assisted extraction technique. Current Research in Food Science 2021, 4, 478 -488.

AMA Style

Vidhi H. Bhimjiyani, Venu Babu Borugadda, Satyanarayan Naik, Ajay K. Dalai. Enrichment of flaxseed (Linum usitatissimum) oil with carotenoids of sea buckthorn pomace via ultrasound-assisted extraction technique. Current Research in Food Science. 2021; 4 ():478-488.

Chicago/Turabian Style

Vidhi H. Bhimjiyani; Venu Babu Borugadda; Satyanarayan Naik; Ajay K. Dalai. 2021. "Enrichment of flaxseed (Linum usitatissimum) oil with carotenoids of sea buckthorn pomace via ultrasound-assisted extraction technique." Current Research in Food Science 4, no. : 478-488.

Review
Published: 21 July 2021 in Reactions
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Light olefins as one the most important building blocks in chemical industry can be produced via Fischer–Tropsch synthesis (FTS) from syngas. FT synthesis conducted at high temperature would lead to light paraffins, carbon dioxide, methane, and C5+ longer chain hydrocarbons. The present work focuses on providing a critical review on the light olefin production using Fischer–Tropsch synthesis. The effects of metals, promoters and supports as the most influential parameters on the catalytic performance of catalysts are discussed meticulously. Fe and Co as the main active metals in FT catalysts are investigated in terms of pore size, crystal size, and crystal phase for obtaining desirable light olefin selectivity. Larger pore size of Fe-based catalysts is suggested to increase olefin selectivity via suppressing 1-olefin readsorption and secondary reactions. Iron carbide as the most probable phase of Fe-based catalysts is proposed for light olefin generation via FTS. Smaller crystal size of Co active metal leads to higher olefin selectivity. Hexagonal close-packed (HCP) structure of Co has higher FTS activity than face-centered cubic (FCC) structure. Transition from Co to Co3C is mainly proposed for formation of light olefins over Co-based catalysts. Moreover, various catalysts’ deactivation routes are reviewed. Additionally, techno-economic assessment of FTS plants in terms of different costs including capital expenditure and minimum fuel selling price are presented based on the most recent literature. Finally, the potential for global environmental impacts associated with FTS plants including atmospheric and toxicological impacts is considered via lifecycle assessment (LCA).

ACS Style

Arash Yahyazadeh; Ajay Dalai; Wenping Ma; Lifeng Zhang. Fischer–Tropsch Synthesis for Light Olefins from Syngas: A Review of Catalyst Development. Reactions 2021, 2, 227 -257.

AMA Style

Arash Yahyazadeh, Ajay Dalai, Wenping Ma, Lifeng Zhang. Fischer–Tropsch Synthesis for Light Olefins from Syngas: A Review of Catalyst Development. Reactions. 2021; 2 (3):227-257.

Chicago/Turabian Style

Arash Yahyazadeh; Ajay Dalai; Wenping Ma; Lifeng Zhang. 2021. "Fischer–Tropsch Synthesis for Light Olefins from Syngas: A Review of Catalyst Development." Reactions 2, no. 3: 227-257.

Journal article
Published: 13 July 2021 in Journal of Environmental Chemical Engineering
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Coffee is a relevant agricultural product and one of the most consumed hot beverages globally. To assess the impact of pyrolysis temperatures (400–600 ℃) and heating rates from 5 to 20 ℃/min on the biochar production yields and textural characteristics, spent coffee grounds was subjected to slow-pyrolysis in a pilot-scale reactor. Further, complementary spectroscopic and textural analyses were executed to evaluate the impacts of pyrolysis temperatures on the corresponding biochar surface properties including textural characteristics, reactivity, and surface functionalities. The correlation of pyrolysis temperature with change in biochar’s surface properties along with CO2 mitigation efficiency is examined. The ultimate analysis, FTIR spectroscopy, 13C NMR spectroscopy and Raman scattering measurements confirmed an increment in the degree of aromaticity or decomposition of organic complexes in biochar. The development of basic surface functionalities after the thermal treatment was ascertained by XPS and NEXAFS analyses. Based on the surface composition and textural properties, the CO2 adsorption capacity of SCG-600 was assessed under varying adsorption temperatures at ambient pressure employing a fixed-bed reactor. In this investigation, SCG-600 showed a large CO2 uptake of 2.8 mmol/g under a typical post-combustion scenario. CO2 adsorption mechanism followed the pseudo-first-order kinetics and lower activation energy over varying investigated temperatures reveals the binding process is physical in nature. SCG-600 could be proposed as promising biochar that possesses a combination of higher surface area, well-developed microporous structure, heterogeneous and basic surface functional moieties to meet the specific requirements in dynamic CO2 adsorption.

ACS Style

Alivia Mukherjee; Venu Babu Borugadda; James J. Dynes; Catherine Niu; Ajay K. Dalai. Carbon dioxide capture from flue gas in biochar produced from spent coffee grounds: Effect of surface chemistry and porous structure. Journal of Environmental Chemical Engineering 2021, 9, 106049 .

AMA Style

Alivia Mukherjee, Venu Babu Borugadda, James J. Dynes, Catherine Niu, Ajay K. Dalai. Carbon dioxide capture from flue gas in biochar produced from spent coffee grounds: Effect of surface chemistry and porous structure. Journal of Environmental Chemical Engineering. 2021; 9 (5):106049.

Chicago/Turabian Style

Alivia Mukherjee; Venu Babu Borugadda; James J. Dynes; Catherine Niu; Ajay K. Dalai. 2021. "Carbon dioxide capture from flue gas in biochar produced from spent coffee grounds: Effect of surface chemistry and porous structure." Journal of Environmental Chemical Engineering 9, no. 5: 106049.

Journal article
Published: 12 July 2021 in Chemosphere
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The optimization of process parameters for biochar activation is crucial for enhancing its surface area and adsorptive potentials. This work attempts to investigate the influence of activating agent (e.g., steam and KOH), temperature (700–900 °C) and activation time (60–120 min) using Taguchi L18 (21 × 32) experimental design for the activation of biochar derived from food waste and agricultural crop residues such as canola hull and oat hull. Among all the factors, activating agent and temperature influenced surface area considerably. KOH-assisted chemical activation of biochar at 800 °C for 90 min was found to be optimal with higher specific surface areas of 1760, 1718 and 1334 m2/g for food waste, canola hull and oat hull derived biochar, respectively. Finally, the comparative evaluation of the performances of biochar and activated carbon samples was achieved through the adsorption of common dyes such as methylene blue, methyl violet and rhodamine B. Activated carbon samples derived from food waste biochar and canola hull biochar exhibited a complete removal of methylene blue and methyl violet from model aqueous solution within 1–2 h of contact time at room temperature, whereas in case of rhodamine B only 91–94% removal was achieved.

ACS Style

Biswa R. Patra; Sonil Nanda; Ajay K. Dalai; Venkatesh Meda. Taguchi-based process optimization for activation of agro-food waste biochar and performance test for dye adsorption. Chemosphere 2021, 285, 131531 .

AMA Style

Biswa R. Patra, Sonil Nanda, Ajay K. Dalai, Venkatesh Meda. Taguchi-based process optimization for activation of agro-food waste biochar and performance test for dye adsorption. Chemosphere. 2021; 285 ():131531.

Chicago/Turabian Style

Biswa R. Patra; Sonil Nanda; Ajay K. Dalai; Venkatesh Meda. 2021. "Taguchi-based process optimization for activation of agro-food waste biochar and performance test for dye adsorption." Chemosphere 285, no. : 131531.

Journal article
Published: 05 July 2021 in Chemosphere
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Effective management and utilization of food waste and agricultural crop residues are highly crucial to mitigate the challenges of greenhouse gas generation upon natural decomposition and waste accumulation. Conversion of biogenic wastes to biofuels and bioproducts can address the energy crisis and promote environmental remediation. This study was focused on exploring the characteristics of food waste and agricultural crop residues (e.g., canola hull and oar hull) to determine their candidacy for slow pyrolysis to produce biochar and bio-oil. Process parameters of slow pyrolysis such as temperature, reaction time and heating rate were optimized to obtain maximum biochar yields. Maximum biochar yield of 28.4 wt% was recorded at optimized temperature, heating rate and reaction time of 600 °C, 5 °C/min and 60 min, respectively. Furthermore, the physicochemical, spectroscopic and microscopic characterization of biochar, bio-oil and gases were performed. The carbon content and thermal stability of biochar were found to increase at higher temperatures. Moreover, bio-oil generated at higher temperatures showed the presence of phenolics and aromatic compounds.

ACS Style

Biswa R. Patra; Sonil Nanda; Ajay K. Dalai; Venkatesh Meda. Slow pyrolysis of agro-food wastes and physicochemical characterization of biofuel products. Chemosphere 2021, 285, 131431 .

AMA Style

Biswa R. Patra, Sonil Nanda, Ajay K. Dalai, Venkatesh Meda. Slow pyrolysis of agro-food wastes and physicochemical characterization of biofuel products. Chemosphere. 2021; 285 ():131431.

Chicago/Turabian Style

Biswa R. Patra; Sonil Nanda; Ajay K. Dalai; Venkatesh Meda. 2021. "Slow pyrolysis of agro-food wastes and physicochemical characterization of biofuel products." Chemosphere 285, no. : 131431.

Review
Published: 30 June 2021 in Chemosphere
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The pretreatment of lignocellulosic biomass enhances the conversion efficiency to produce biofuels and value-added chemicals, which have the potential to replace fossil fuels. Compared to physicochemical and other pretreatment techniques, the hydrothermal methods are considered eco-friendly and cost-effective. This paper reviews the strengths, weaknesses, opportunities and threats of steam explosion and subcritical water hydrolysis as the two promising hydrothermal technologies for the pretreatment of lignocellulosic biomass. Although the principle of the steam explosion in depolymerizing the lignin and exposing the cellulose fibers for bioconversion to liquid fuels is well known, its underlying mechanism for solid biofuel production is less identified. Therefore, this review provides an insight into different operating conditions of steam explosion and subcritical water hydrolysis for a wide variety of feedstocks. The mechanisms of subcritical water hydrolysis including dehydration, decarboxylation and carbonization of waste biomass are comprehensively described. Finally, the role of microwave heating in the hydrothermal pretreatment of biomass is elucidated.

ACS Style

Tumpa R. Sarker; Falguni Pattnaik; Sonil Nanda; Ajay K. Dalai; Venkatesh Meda; Satyanarayan Naik. Hydrothermal pretreatment technologies for lignocellulosic biomass: A review of steam explosion and subcritical water hydrolysis. Chemosphere 2021, 284, 131372 .

AMA Style

Tumpa R. Sarker, Falguni Pattnaik, Sonil Nanda, Ajay K. Dalai, Venkatesh Meda, Satyanarayan Naik. Hydrothermal pretreatment technologies for lignocellulosic biomass: A review of steam explosion and subcritical water hydrolysis. Chemosphere. 2021; 284 ():131372.

Chicago/Turabian Style

Tumpa R. Sarker; Falguni Pattnaik; Sonil Nanda; Ajay K. Dalai; Venkatesh Meda; Satyanarayan Naik. 2021. "Hydrothermal pretreatment technologies for lignocellulosic biomass: A review of steam explosion and subcritical water hydrolysis." Chemosphere 284, no. : 131372.

Journal article
Published: 29 June 2021 in Biomass and Bioenergy
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The hydrochar, a by-product of hydrothermal liquefaction (HTL) of algal biomass, was utilized through two methods; combustion and activation, for its usage as a source of heat and a catalyst support for hydrodeoxygenation (HDO) process in the production of algal biofuels. In this study, techno-economic analysis (TEA) and life cycle assessment (LCA) of algal biofuels production in a two-stage process (HTL and HDO) were investigated. Aspen plus simulation and SimaPro software were used to analyze process economics and greenhouse gas (GHG) emissions. Microalgae at 200 dry metric tonnes day−1 was the basis for its conversion to biocrude oil through HTL in the methanol-water system followed by catalytic upgrading to produce biofuels. According to HTL experimental results, maximum biocrude oil yield of 57.8 wt% was obtained using microalgae-solvent mass ratio and methanol-water mass ratio of 1:5 and 3:1, respectively. Produced biocrude oil contained 14.5 wt% of oxygen and HHV of 33.4 MJ kgbiocrude oil−1 which required upgrading to be utilized as a transportation fuel. HDO was employed to enhance the quality of biocrude oil with decrease in oxygen content (3.1 wt%) and increase in HHV (42 MJ kgbiofuel−1). The minimum fuel selling price (MFSP) for using method #2 (activation) was 2.2 $ L−1 to breakeven the cost of operation, which was about 10% lower than that from method #1 (combustion). The GHG emissions performance was estimated at −1.13 gCO2-eq MJ−1 indicating the significant GHG emissions reduction compared to petroleum-based fuels production.

ACS Style

Shima Masoumi; Ajay K. Dalai. Techno-economic and life cycle analysis of biofuel production via hydrothermal liquefaction of microalgae in a methanol-water system and catalytic hydrotreatment using hydrochar as a catalyst support. Biomass and Bioenergy 2021, 151, 106168 .

AMA Style

Shima Masoumi, Ajay K. Dalai. Techno-economic and life cycle analysis of biofuel production via hydrothermal liquefaction of microalgae in a methanol-water system and catalytic hydrotreatment using hydrochar as a catalyst support. Biomass and Bioenergy. 2021; 151 ():106168.

Chicago/Turabian Style

Shima Masoumi; Ajay K. Dalai. 2021. "Techno-economic and life cycle analysis of biofuel production via hydrothermal liquefaction of microalgae in a methanol-water system and catalytic hydrotreatment using hydrochar as a catalyst support." Biomass and Bioenergy 151, no. : 106168.

Journal article
Published: 01 June 2021 in Biomass and Bioenergy
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Agricultural wastes have the potential to contribute to global energy by converting low value by-products to high value products e.g. fuel pellets, which can be used for heat and power generation. In this study, co-pelletizing characteristics of canola hull, oat hull and barley straw with water were investigated while pyrolysis bio-oil was used as binder. Co-pelletization has been conducted using bench-scale extruder. Canola hull was used as base feedstock due to having a small portion of oil (8 wt%) which provides lubricating effects during pelletization. Increase in biomass to water mass ratio, increased the mechanical strength and durability of pellets but pellets yield decreased. The optimum biomass to water mass ratio was found 2.5. Pyrolysis bio-oil worked as effective additives, enhanced the flow properties, made extrusion smooth, advanced the internal structure of pellet by facilitating strong interlocking of particles, and thus boosted the physical firmness of fuel pellet. Results showed that co-pelletization of oat hull and barley straw with canola hull was optimum for 30 wt% of oat hull or barley straw, but pelletization was successful for up to 45 wt% of those feedstocks. Microwave torrefaction was conducted to boost up the hydrophobicity and higher heating value of pellet. Torrefied pellet showed higher heating value, higher energy density, higher carbon content, lower atomic ratio, lower moisture uptake rate compared to untreated pellet. Synchrotron-based computed tomography shows that porosity increased by up to 39% after torrefaction. Additionally, to assess the mechanical, physical and chemical properties of pellet, various characterization methods were employed.

ACS Style

Tumpa Rani Sarker; Ramin Azargohar; Ajay K. Dalai; Venkatesh Meda. Characteristics of torrefied fuel pellets obtained from co-pelletization of agriculture residues with pyrolysis oil. Biomass and Bioenergy 2021, 150, 106139 .

AMA Style

Tumpa Rani Sarker, Ramin Azargohar, Ajay K. Dalai, Venkatesh Meda. Characteristics of torrefied fuel pellets obtained from co-pelletization of agriculture residues with pyrolysis oil. Biomass and Bioenergy. 2021; 150 ():106139.

Chicago/Turabian Style

Tumpa Rani Sarker; Ramin Azargohar; Ajay K. Dalai; Venkatesh Meda. 2021. "Characteristics of torrefied fuel pellets obtained from co-pelletization of agriculture residues with pyrolysis oil." Biomass and Bioenergy 150, no. : 106139.

Journal article
Published: 14 May 2021 in Fuel
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TUD-1 supported bifunctional platinum catalysts were prepared and characterized for structural and textural properties, acidity, and platinum dispersion. The acidity of TUD-1 was varied by isomorphous substitution of Al and Ti in the framework. The TUD-1 supports possess a three-dimensional amorphous structure as shown by XRD. BET-N2 adsorption and pyridine FTIR studies revealed that the incorporation of Al in the TUD-1 framework enhances the surface area and generates Brønsted acidity. The catalysts were screened for hydrorefining of Fischer-Tropsch wax with C8-C44 n-paraffins. The catalysts prepared with Si-TUD-1 and Ti-TUD-1 supports were not active for hydrocracking and hydroisomerization due to the absence of Brønsted acid sites, which was verified by pyridine FTIR. Increasing the amount of Al in the framework gradually increased the Brønsted acid sites and thus promoted hydrocracking and hydroisomerization of F-T wax. Pt/Al-TUD-1 catalyst with a Si/Al ratio of 10 produced more jet fuel range hydrocarbons. Hydrorefining of F-T wax was evaluated over an optimal Pt/Al-TUD-1 (Si/Al = 10) catalyst at different pressures and temperatures. Hydroisomerization was favored at low hydrogen pressure. Increasing the temperature shifted the hydrocarbon distribution more towards gasoline due to severe cracking. The temperature of 330 °C and a hydrogen pressure of 5 MPa were found to be optimum to produce jet fuel range hydrocarbons that meet the ASTM specification of cold flow properties. This study proves the feasibility of the production of renewable jet fuel that is directly compatible with fossil-based aviation engines, through hydrorefining of F-T waxes using a mesoporous bifunctional catalyst.

ACS Style

Sundaramurthy Vedachalam; Philip Boahene; Ajay K. Dalai. Production of jet fuel by hydrorefining of Fischer-Tropsch wax over Pt/Al-TUD-1 bifunctional catalyst. Fuel 2021, 300, 121008 .

AMA Style

Sundaramurthy Vedachalam, Philip Boahene, Ajay K. Dalai. Production of jet fuel by hydrorefining of Fischer-Tropsch wax over Pt/Al-TUD-1 bifunctional catalyst. Fuel. 2021; 300 ():121008.

Chicago/Turabian Style

Sundaramurthy Vedachalam; Philip Boahene; Ajay K. Dalai. 2021. "Production of jet fuel by hydrorefining of Fischer-Tropsch wax over Pt/Al-TUD-1 bifunctional catalyst." Fuel 300, no. : 121008.

Special issue article
Published: 14 May 2021 in The Canadian Journal of Chemical Engineering
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Geopolymer is a porous aluminosilicate material and chemically similar to zeolites. As a low‐cost construction material, its suitability for adsorptive desulphurization (ADS) was studied using a petroleum feedstock. Geopolymer was produced by alkali activation of metakaolin and characterized by BET, NH3–TPD, SEM, FTIR, XRD, and XPS. The XRD and SEM studies evidenced the amorphous nature of geopolymer and the existence of macro‐ and mesopores. The XPS and NH3–TPD studies revealed the presence of surface Na and Al, and strong acid sites, respectively, in the prepared geopolymer. These sites interact with sulphur compounds of heavy gas oil through π‐π and acid‐base interactions. The geopolymer showed a high sulphur adsorption capacity of 38.4 mg/g. The effects of adsorption parameters such as operating temperature, amount of adsorbent, and time for absorption on the adsorption capacity were examined using the Box–Behnken design statistical model. All three operating parameters significantly influenced the sulphur adsorption capacity of geopolymer. The adsorption of sulphur compounds on the geopolymer followed pseudo‐first‐order kinetics and did not affect its structural stability. Finally, the thermodynamic study revealed that adsorption of sulphur compounds on the geopolymer was spontaneous and exothermic.

ACS Style

Biswajit Saha; Sundaramurthy Vedachalam; Ajay K. Dalai. Performance of geopolymer as adsorbent on desulphurization of heavy gas oil. The Canadian Journal of Chemical Engineering 2021, 1 .

AMA Style

Biswajit Saha, Sundaramurthy Vedachalam, Ajay K. Dalai. Performance of geopolymer as adsorbent on desulphurization of heavy gas oil. The Canadian Journal of Chemical Engineering. 2021; ():1.

Chicago/Turabian Style

Biswajit Saha; Sundaramurthy Vedachalam; Ajay K. Dalai. 2021. "Performance of geopolymer as adsorbent on desulphurization of heavy gas oil." The Canadian Journal of Chemical Engineering , no. : 1.

Review
Published: 05 May 2021 in Chemical Engineering Science
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The rise in the temperature contributing to global warming is attributed to the increased human-generated greenhouse gas emission in the ambient atmosphere. In this paper, firstly, a comprehensive overview of the capture technologies is presented, highlighting the post-combustion capture technology as one of the promising CO2 mitigation strategies. The performance of activated carbon, amine-functionalized and metal-oxide impregnated materials prepared from renewable precursors as the acknowledged adsorbents are well assessed and presented systematically. Conversion of CO2 is proposed as a sustainable practice to substitute for dwindling fossil fuels. A strong emphasis is put on the conversion of CO2 into value-added chemicals like higher hydrocarbons via series of catalytic-hydrogenation reactions. The specific aim of this study is to assist researchers by providing a holistic overview of different aspects of carbon-based adsorbents for post-combustion capture instead of the current-state-of art technology and enhancing the pathways for CO2 valorization to clean and renewable end-products.

ACS Style

S.R. Shewchuk; A. Mukherjee; A.K. Dalai. Selective carbon-based adsorbents for carbon dioxide capture from mixed gas streams and catalytic hydrogenation of CO2 into renewable energy source: A review. Chemical Engineering Science 2021, 243, 116735 .

AMA Style

S.R. Shewchuk, A. Mukherjee, A.K. Dalai. Selective carbon-based adsorbents for carbon dioxide capture from mixed gas streams and catalytic hydrogenation of CO2 into renewable energy source: A review. Chemical Engineering Science. 2021; 243 ():116735.

Chicago/Turabian Style

S.R. Shewchuk; A. Mukherjee; A.K. Dalai. 2021. "Selective carbon-based adsorbents for carbon dioxide capture from mixed gas streams and catalytic hydrogenation of CO2 into renewable energy source: A review." Chemical Engineering Science 243, no. : 116735.

Review paper
Published: 20 April 2021 in International Journal of Energy Research
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Rapid industrialization, increasing fuel prices, exhausting fossil fuel resources and greenhouse gas emissions are some of the factors instilling the search for alternative sources of energy and chemicals. Lignocellulose biomass‐derived biofuels and biochemicals have emerged as clean products to complement fossil‐based resources and reduce environmental impacts. Lignocellulosic biomasses are renewable, inexpensive and abundantly available resources to produce a wide variety of liquid, gaseous and solid biofuels and industrially relevant biochemicals. Different biological (e.g., fermentation and anaerobic digestion), thermochemical (e.g., liquefaction, gasification and pyrolysis) and catalytic (e.g., transesterification) conversion technologies can be used to produce fuel and chemical products from lignocellulosic biomass. This article makes a comprehensive review of different biofuels (e.g., biodiesel, bio‐oil, bioethanol, biobutanol, biogas, hydrogen, syngas and jetfuel) and value‐added biochemicals (e.g., propylene, ethylene, benzene, 5‐hydroxymethylfurfural, levulinic acid, succinic acid, maleic acid, fumaric acid, phenols and other aromatic compounds) from lignocellulosic biomass. Additionally, the current status, challenges and future perspectives for the production and utilization of biofuels and biochemicals are systematically discussed.

ACS Style

Jude A. Okolie; Alivia Mukherjee; Sonil Nanda; Ajay K. Dalai; Janusz A. Kozinski. Next‐generation biofuels and platform biochemicals from lignocellulosic biomass. International Journal of Energy Research 2021, 1 .

AMA Style

Jude A. Okolie, Alivia Mukherjee, Sonil Nanda, Ajay K. Dalai, Janusz A. Kozinski. Next‐generation biofuels and platform biochemicals from lignocellulosic biomass. International Journal of Energy Research. 2021; ():1.

Chicago/Turabian Style

Jude A. Okolie; Alivia Mukherjee; Sonil Nanda; Ajay K. Dalai; Janusz A. Kozinski. 2021. "Next‐generation biofuels and platform biochemicals from lignocellulosic biomass." International Journal of Energy Research , no. : 1.

Research article
Published: 15 April 2021 in Industrial & Engineering Chemistry Research
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Supercritical water gasification is a hydrothermal process to gasify complex organic biomass to produce hydrogen-rich syngas. This study reports the catalytic performance and hydrogen selectivity of several Ni-based catalysts during supercritical water gasification of soybean straw. All experiments were performed at a temperature, an average biomass particle size, a feedstock/water ratio, and a residence time 500 °C, 0.13 mm, 1:10, and 45 min, respectively. A comprehensive screening of different support materials ranging from activated carbon (AC), carbon nanotubes (CNTs), ZrO2, Al2O3, SiO2, and Al2O3–SiO2 was performed at 10 wt % Ni loading. The effectiveness of each support in improving H2 yield and selectivity was in the order ZrO2 > Al2O3 > AC > CNT > SiO2 > Al2O3–SiO2. The effects of adding three promoters (i.e., Na, K, and Ce) to the supported Ni/ZrO2 and Ni/Al2O3 catalysts were evaluated. In terms of H2 yield, the performance of each promoter for Ni/ZrO2 catalysts was in the order Ce (10.9 mmol/g) > K (10.3 mmol/g) > Na (9.5 mmol/g). Cerium showed better performance in promoting H2 yield and minimizing coke deposition on the support. The addition of K, Na, and Ce promoters elevated Ni dispersion and the metallic surface area, thus improving H2 yields.

ACS Style

Jude A. Okolie; Alivia Mukherjee; Sonil Nanda; Ajay K. Dalai; Janusz A. Kozinski. Catalytic Supercritical Water Gasification of Soybean Straw: Effects of Catalyst Supports and Promoters. Industrial & Engineering Chemistry Research 2021, 60, 5770 -5782.

AMA Style

Jude A. Okolie, Alivia Mukherjee, Sonil Nanda, Ajay K. Dalai, Janusz A. Kozinski. Catalytic Supercritical Water Gasification of Soybean Straw: Effects of Catalyst Supports and Promoters. Industrial & Engineering Chemistry Research. 2021; 60 (16):5770-5782.

Chicago/Turabian Style

Jude A. Okolie; Alivia Mukherjee; Sonil Nanda; Ajay K. Dalai; Janusz A. Kozinski. 2021. "Catalytic Supercritical Water Gasification of Soybean Straw: Effects of Catalyst Supports and Promoters." Industrial & Engineering Chemistry Research 60, no. 16: 5770-5782.

Journal article
Published: 08 April 2021 in Environmental Pollution
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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 (0.13 mm and 0.8 mm) using the statistical Taguchi method. Maximum hydrogen yield and total gas yield of 5.26 mmol/g and 11.88 mmol/g, respectively were obtained under optimized process conditions at 500 °C in 45 min with 10 wt% feed concentration using biomass particle size of 0.13 mm. The results from the mean of hydrogen yield show that the contribution of each experimental factors was in the order of temperature > feed concentration > residence time > biomass particle size. Other gaseous products obtained at optimum conditions include CO2 (3.43 mmol/g), CH4 (3.13 mmol/g) and C2–C4 hydrocarbons (0.06 mmol/g).

ACS Style

Jude A. Okolie; Sonil Nanda; Ajay K. Dalai; Janusz A. Kozinski. Optimization studies for hydrothermal gasification of partially burnt wood from forest fires for hydrogen-rich syngas production using Taguchi experimental design. Environmental Pollution 2021, 283, 117040 .

AMA Style

Jude A. Okolie, Sonil Nanda, Ajay K. Dalai, Janusz A. Kozinski. Optimization studies for hydrothermal gasification of partially burnt wood from forest fires for hydrogen-rich syngas production using Taguchi experimental design. Environmental Pollution. 2021; 283 ():117040.

Chicago/Turabian Style

Jude A. Okolie; Sonil Nanda; Ajay K. Dalai; Janusz A. Kozinski. 2021. "Optimization studies for hydrothermal gasification of partially burnt wood from forest fires for hydrogen-rich syngas production using Taguchi experimental design." Environmental Pollution 283, no. : 117040.

Research article
Published: 25 March 2021 in Energy & Fuels
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A biosorbent derived from oat hulls was employed to dehydrate butanol from water mixture to obtain a high-purity butanol product. As this process involves water and butanol binary sorption, it is important to investigate equilibrium of water and butanol sorption on the biosorbent. Previous studies investigated water sorption from a mixture of butanol and water. This work emphasizes the equilibrium of butanol sorption from pure butanol and butanol–water binary systems. The Dubinin–Polanyi models (applicable to micropore and large pore materials), which are equilibrium models derived from the adsorption potential theory of Polanyi, were applied to simulate the experimental data for butanol sorption on the aforementioned biosorbent. The models agreed with the experimental data. The parameter q0 (limiting mass for sorption) was estimated in the butanol–water binary as well as the pure butanol systems. The comparison of q0 from single and binary systems indicated that the competitive sorption occurred between butanol and water on the biosorbent. In order to analyze the energetics of the butanol sorption, the approximate site energy distribution of butanol sorption was further investigated. The results showed that water sorption had a higher value of weighted mean of site energy distribution than butanol sorption. This biosorbent had higher affinity to water and therefore had higher water sorption capacity. The dipole–dipole attraction, one kind of van der Waals force, could be one of the key mechanisms of butanol sorption by the biosorbent. Additionally, thermodynamic parameters were determined. The results indicated that the butanol sorption process was spontaneous and exothermic.

ACS Style

Qian Huang; Ajay Kumar Dalai; Lifeng Zhang; Catherine Hui Niu. Equilibrium Study and Analysis of Site Energy Distribution of Butanol Sorption on a Biosorbent. Energy & Fuels 2021, 35, 6681 -6690.

AMA Style

Qian Huang, Ajay Kumar Dalai, Lifeng Zhang, Catherine Hui Niu. Equilibrium Study and Analysis of Site Energy Distribution of Butanol Sorption on a Biosorbent. Energy & Fuels. 2021; 35 (8):6681-6690.

Chicago/Turabian Style

Qian Huang; Ajay Kumar Dalai; Lifeng Zhang; Catherine Hui Niu. 2021. "Equilibrium Study and Analysis of Site Energy Distribution of Butanol Sorption on a Biosorbent." Energy & Fuels 35, no. 8: 6681-6690.

Journal article
Published: 23 March 2021 in Molecular Catalysis
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Hydrodeoxygenation of oleic acid was performed using NiMo-based catalyst supported on several mesoporous supports such as γ-Al2O3, SBA-15 and hexagonal mesoporous silica (HMS) in batch mode at 350−410 °C under H2 pressure of 6.9 MPa. The catalysts were synthesized using incipient wet impregnation with approximately 12 wt.% Mo and 4 wt.% Ni loadings. Among the synthesized catalysts, NiMo/SBA-15 demonstrated the highest surface area (484 m2/g) and average pore diameter (9.4 nm). Moreover, γ-Al2O3 showed better catalytic activity during hydrodeoxygenation compared to SBA-15 and HMS supports. At hydrotreating conditions (390 °C and 6.9 MPa), NiMo/γ-Al2O3 showed 77 % oxygen removal and 42 % selectivity towards C16-C18 alkanes during 8 h of batch reaction. To elucidate the promotional effects, bimetallic catalyst (NiMo/γ-Al2O3) promoted with Cu, Cr and Fe (CuNiMo/γ-Al2O3, CrNiMo/γ-Al2O3 and FeNiMo/γ-Al2O3) catalysts were used for hydrodeoxygenation of oleic acid. CuNiMo/γ-Al2O3 gave the highest conversion (ca. 92 %) during hydrodeoxygenation at 300 °C, 6.9 MPa H2 pressure and 600 rpm agitation speed.

ACS Style

Naveenji Arun; Sonil Nanda; Yongfeng Hu; Ajay K. Dalai. Hydrodeoxygenation of oleic acid using γ-Al2O3 supported transition metallic catalyst systems: Insight into the development of novel FeCu/γ-Al2O3 catalyst. Molecular Catalysis 2021, 111526 .

AMA Style

Naveenji Arun, Sonil Nanda, Yongfeng Hu, Ajay K. Dalai. Hydrodeoxygenation of oleic acid using γ-Al2O3 supported transition metallic catalyst systems: Insight into the development of novel FeCu/γ-Al2O3 catalyst. Molecular Catalysis. 2021; ():111526.

Chicago/Turabian Style

Naveenji Arun; Sonil Nanda; Yongfeng Hu; Ajay K. Dalai. 2021. "Hydrodeoxygenation of oleic acid using γ-Al2O3 supported transition metallic catalyst systems: Insight into the development of novel FeCu/γ-Al2O3 catalyst." Molecular Catalysis , no. : 111526.

Review
Published: 19 March 2021 in Reactions
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This review emphasizes the importance of the catalytic conversion techniques in the production of clean liquid and hydrogen fuels (XTF) and chemicals (XTC) from the carbonaceous materials including coal, natural gas, biomass, organic wastes, biogas and CO2. Dependence of the performance of Fischer–Tropsch Synthesis (FTS), a key reaction of the XTF/XTC process, on catalyst structure (crystal and size) is comparatively examined and reviewed. The contribution illustrates the very complicated crystal structure effect, which indicates that not only the particle type, but also the particle shape, facets and orientation that have been evidenced recently, strongly influence the catalyst performance. In addition, the particle size effects over iron, cobalt and ruthenium catalysts were carefully compared and analyzed. For all Fe, Co and Ru catalysts, the metal turnover frequency (TOF) for CO hydrogenation increased with increasing metal particle size in the small size region i.e., less than the size threshold 7–8 nm, but was found to be independent of particle size for the catalysts with large particle sizes greater than the size threshold. There are some inconsistencies in the small particle size region for Fe and Ru catalysts, i.e., an opposite activity trend and an abnormal peak TOF value were observed on a Fe catalyst and a Ru catalyst (2 nm), respectively. Further study from the literature provides deeper insights into the catalyst behaviors. The intrinsic activity of Fe catalysts (10 nm) at 260–300 °C is estimated in the range of 0.046–0.20 s−1, while that of the Co and Ru catalysts (7–70 nm) at 220 °C are 0.1 s−1 and 0.4 s−1, respectively.

ACS Style

Wenping Ma; Ajay Dalai. Effects of Structure and Particle Size of Iron, Cobalt and Ruthenium Catalysts on Fischer–Tropsch Synthesis. Reactions 2021, 2, 62 -77.

AMA Style

Wenping Ma, Ajay Dalai. Effects of Structure and Particle Size of Iron, Cobalt and Ruthenium Catalysts on Fischer–Tropsch Synthesis. Reactions. 2021; 2 (1):62-77.

Chicago/Turabian Style

Wenping Ma; Ajay Dalai. 2021. "Effects of Structure and Particle Size of Iron, Cobalt and Ruthenium Catalysts on Fischer–Tropsch Synthesis." Reactions 2, no. 1: 62-77.