Presence Of KOH Research Articles

High removal of volatile organic compounds on hierarchical carbons prepared from agro-industrial waste of banana fruit production for air decontamination.

Activated carbons were prepared from residues from agro-industrial banana production (banana pseudostem) and evaluated in the capture of five different volatile organic compounds (VOCs): dichloromethane, chloroform, ethyl acetate, hexane, and cyclohexane. The biomass was first submitted to a hydrothermal treatment in the presence of KOH or ZnCl2 as activating agents, followed by a dry pyrolysis. This new advance in methodology contributes to producing activated carbons with hierarchical porosity and high surface areas (701-1312 m2g-1), promoting increased interest in managing waste from banana fruit agricultural production. VOC capture studies were performed by thermal analysis, and capture capacities were similar to or higher than those presented in the literature. Higher adsorption capacities were related to the amount of available micropores, and the capture capacity was enhanced by the contribution of small mesopores. As the highest adsorbed amounts of dichloromethane (933mgg-1 at 25°C) were obtained for the material activated with ZnCl2 (1:3), further studies were carried out for this system. The experimental data was fitted using a pseudo-first-order kinetic model. A study was carried out in different atmospheres (He, N2, air), showing that co-adsorption is occurring. Under simulated environmental conditions, the capture capacity decreased slightly at equilibrium, and the new adsorbent was used for up to ten cycles without significantly losing its efficiency, indicating good application in the field.

NiCo2O4-Nanoparticle-Catalyzed Microwave-Assisted Dehydrogenative Direct Oxidation of Primary Alcohols to Carboxylic Acids under Oxidant-Free Conditions

AbstractHere, we report the NiCo2O4-nanoparticle-catalyzed dehydrogenative direct oxidation of primary alcohols to carboxylic acid in the presence of KOH under microwave irradiation in the absence of any oxidant in good to excellent yields (75–99%) within a short reaction time (5–10 min). The polycrystalline cubic spinel phase of NiCo2O4 nanoparticles (NPs) with an average size of 25 nm were synthesized by the co-precipitation method and analyzed properly by using powder X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy measurements. The NiCo2O4 NPs were stable under the reaction conditions and reused for up to eight cycles without appreciable loss in the yield of benzoic acid. According to mechanistic insight, the KOH acts as a second oxygen source and is essential for the synthesis of carboxylic acid from alcohols. The hydrogen gas was found to be the only byproduct of this method detected by chemical reactions.

Base-Promoted Annulated Aromatization of Aryl Acetylenes with Dimethyl Sulfoxide to Access Symmetrical/Unsymmetric m-Terphenyl.

A protocol for selective and efficient synthesis of symmetrical and unsymmetrical m-terphenyls is presented among aryl acetylene and DMSO in the presence of KOH and methanol. In this reaction, two molecules of aryl acetylene contribute four carbons, and DMSO, as a dual carbon donor, provides two carbons to a new aromatic ring. This protocol can be tolerated for the electron-donating or disubstituted phenylacetylenes as well as the heterocyclic acetylene derivatives.

Synthesis, characterization, and investigation of catalytic properties of RuII complexes with Schiff bases based on 2-hydroxybenzaldehyde and 5-bromo-2-hydroxybenzaldehyde

Pursuing our recent interest concerning the catalytic activity of half-sandwich RuII complexes containing Schiff base ligands (L1 and L2), in this study new Schiff bases and their half-sandwich RuII complexes were prepared. The structures of these compounds were confirmed by a variety of spectral and physical methods such as microanalysis, FT-IR, electronic spectra, proton and carbon NMR, TGA and mass spectra. The catalytic activities of the RuII complexes toward the transfer hydrogenation of ketones to their corresponding alcohols were investigated using i-PrOH as a hydrogen source and solvent. The complexes showed high catalytic activities at catalyst concentrations of 0.01 mmol and were able to carry out transfer hydrogenation (TH) to a wide range of ketones in the presence of KOH. In general, Schiff bases recognition, the coordination chemistry, and the ketone substrates were found to influence the catalytic performance of these complexes.

Synthesis of Amides via the Amination of Aldehydes with Hydroxylamines Promoted by TBAF·3H2O.

A metal-free, mild, and efficient method for the synthesis of amides has been developed from the amination of aldehydes with hydroxylamines promoted by TBAF·3H2O in the presence of KOH. Control experiments showed that the nitrone was the intermediate of this amination. By this method, a series of amides, biologically active compounds bebenil and a COX inhibitor were obtained in moderate to good yields.

Controlled Synthesis of Bead‐like Pt as an Efficient Electrocatalyst for Electrocatalytic Ammonia Oxidation

AbstractPromoting electrocatalytic ammonia oxidation reaction (AOR) holds the key to develop efficient direct ammonia fuel cells (DAFCs) and ammonia‐mediated hydrogen production (AMHP). Recent investigations indicated that Pt with the exposure of (100) facet has a moderate *N intermediate bonding strength, resulting in the highest AOR electrocatalytic activity among others. Therefore, maximizing the exposure of (100) planes with high active surface area is highly desired for efficient electrocatalysts. In this paper, Pt catalyst composed of directional alignment of nanoparticles around 50 nm (Pt‐100/C) were synthesized by hydrothermal method in the presence of KOH. The KOH concentration was found to modulate the one‐dimensional alignment of nanoparticles. The electrocatalyst showed the largest electrochemically active areas and the highest peak current density (3.14 mA cm−2), and the catalyst exhibited high stability after 500 cycles. A series of electrochemical tests and structural characterizations show that unique bead‐structured Pt combines the excellent activity of nanoparticles with the structural stability of nanowires. A scheme for “exchanging electrodes” has been proposed to solve the problem of catalyst poisoning caused by AOR in AMHP.

Evaluation of bovine carbonic anhydrase for promoting CO2 capture via reaction with KOH and high-salinity reject brine

In this study, we investigate the preliminary effect of bovine carbonic anhydrase (BCA) catalyst on CO2 capture via a reaction with potassium hydroxide (KOH) and reject brine under different operational conditions. Experiments were performed at a constant gauge pressure of 2 bar, with a CO2 inlet concentration of 10% and a CO2 flow rate of 776 mL/min. First, the impact of the BCA catalyst on CO2 capture in the absence of the alkaline material (KOH) was studied. Results showed that using 3-mg/L BCA increases the CO2 capture by 181% compared with the case without BCA. Second, the effect of BCA on CO2 uptake and ions reduction was examined in the presence of KOH. At a KOH concentration of 10-g/L, BCA concentration of 50-mg/L, and temperature of 40℃, a CO2 uptake value of 0.08 g CO2/g KOH was obtained. In comparison, adding 30-g/L KOH and 50-mg/L BCA increased the CO2 uptake by 737.5% (0.67 g CO2/g KOH). Furthermore, the sodium (Na+) reduction percentage reached a maximum of 40.8% at KOH and BCA concentrations of 30 g/L and 50 mg/L, respectively. However, increasing the BCA concentration to 100 mg/L negatively impacted CO2 capture and ion removal, indicating that the BCA concentration could be better optimized to achieve maximum efficiency. Additionally, when the BCA concentration was increased from 50 to 100 mg/L, the reaction rate remained nearly constant at 0.0047 mol/L·min.

One-pot synthesis of highly porous nitrogen and oxygen codoped carbons for solar-driven atmosphere water harvesting

There is significant interest in developing high-performance adsorbents that can harvest water from atmospheric air powered by sunlight. However, The inherent hydrophobicity of porous carbon limits water harvesting capacity. Herein, we report a new class of activated porous carbons (PAK-21) with high water adsorption capacity at moderate to high humidity by solid-phase polymerization of terephthalaldehyde and 2,6-diaminopurine in the presence of KOH under an argon atmosphere at 150 °C for 2 h, and then activated at a high temperature of 700 °C for 1 h. The water harvesting performance surpasses the most common MOFs and porous carbon adsorbents, which benefit from rich surface heterogeneity and highly porous structure. PAK-21 also exhibits fast solar-driven desorption kinetics, ascribing to rapid photothermal responsiveness, hierarchical porosity, and suitable hydrophilicity. Besides, twenty-one adsorption-desorption cycles have been performed to demonstrate its easy regeneration and long-term cyclability. This may pave a new way to modulate the surface functionality and microporous/mesoporous engineering of carbon adsorbents for high-performance solar-driven AWH.

Microporous and Mesoporous Activated Carbons from Tea Stalk and Tea Stalk Pulps: Effect of Lignin Removal by One-Step and Two-Step Organosolv Treatment

Delignification is a crucial pretreatment in the production of diverse value-added products from lignocellulosics. While modifying the surface functional groups, delignification also increases the specific surface area by providing a porous structure to the lignocellulosic biomass. Hydrothermal pretreatment can be used prior to delignification, to recover hemicellulose and boost delignification. By removing lignin and hemicellulose, cellulose-rich pulp becomes more accessible for activation. In the present study, three different activated carbons were prepared: activated carbon from tea stalk itself (ATS), activated carbon from tea stalk pulp obtained by using glycerol organosolv pretreatment (ATP), activated carbon from tea stalk hydrochar pulp obtained by using sequential hydrothermal pretreatment-organosolv delignification (AHTP). Each precursor was carbonized (at 800 °C) in the presence of KOH (KOH/precursor: 2/1). Activated carbons were characterized for their elemental content, surface functional groups, thermal stability, crystallinity, surface morphology, surface area and porous structure using elemental analysis (C-H-N-S), FTIR, TGA, XRD, SEM and, BET analysis, respectively. While hydrothermal pretreatment prior to organosolv pulping reduced the delignification yield, it also altered the pore structure of activated carbon. Among the activated carbons, only ATS had microporous structure with an average pore radius of 1 nm. ATP had the highest surface area (2056.72 m2/g) and micropore volume (0.81 cm3/g). Having mesopores (with an average pore radius of 5.74 nm) in its structure, AHTP had the least micropore volume (0.464 cm3/g) and surface area (1179.71 m2/g). The presence of micro and mesopores broadens the potential applications of activated carbon ranging from environmental applications to energy storage.

Dielectric properties of epoxy/graphite flakes composites: Influence of loading and surface treatment

AbstractEpoxy‐rich carbon‐based composites are well recognized materials in industries owing to their good mechanical properties and thermal stability. Here, dielectric properties of composites based on bisphenol‐A‐epoxy resin loaded with 5, 6, 10, and 15 wt% of graphite flakes (GF) have been studied. The frequency and temperature dependence of the dielectric permittivity, dielectric loss, and ac conductivity have been examined in temperature (−103 to 97°C) and frequency (20 Hz–200 kHz) range. Influence of the filler surface chemistry have been studied for composites loaded with 5 wt% GF obtained: (i) under wet milling, without or with adding Triton‐100x as a surfactant, or (ii) under dry milling in the presence of KOH. The composite made of epoxy loaded with 5 wt% exfoliated expanded graphite flakes (EEG), was also prepared. The surface treatment with KOH notably increased dielectric constant of the composite, keeping low dielectric loss, while treatment with Triton‐100x significantly increased tanδ. The composite loaded with exfoliated expanded graphite shows higher ac conductivity than those obtained with flaky graphite, GF. Possibility to change dielectric properties of the composites without changing the loading content can be used as an approach in tailoring one with desired dielectric properties.

Synthesis, Characterization, Anti-Inflammatory, and Antimicrobial Evaluation of New 2-Pyrazolines Derivatives Derived from Guaiacol

Abstract:
 Chalcones were used to synthesis series of 2-pyrazoline derivatives and evaluated their antimicrobial and anti-inflammatory activities
 (E)-1,3-diphenylprop-2-en-1-one (1-5) were synthesized by Claisen-Schmidt Condensation method through the reaction of acetophenone with five various para substituted benzaldehyde in presence of KOH, the reaction monitoring by TLC and the result intermediates were checked by melting point and FT-IR
 Various 2-Pyrazoline derivatives were prepared by one pot reaction that involved the refluxing of (E)-1,3-diphenylprop-2-en-1-one (1–5) and Hydrazine monohydrate in the presence of glacial acetic acid for 24 hours at a temperature of (45–50) °C for a duration 24 hrs. pyrazoline II (1-5) was formed, then antioxidant compound (guaiacol) was added reflex for 24-48 hours, monitoring by TLC to ensure the reaction was completed. The final mixture was cooled in ice-water bathe until the formation of crystals were completed, added to crushed ice, kept in refrigerator overnight, filter, recrystallized and then dried to get 2-pyrazoline derivatives, IIIa, IIIb, IIIc, IIId and, IIIe. based on the spectral data 2-pyrazoline derivatives structures have been confirmed. The synthesized compounds were screened for their antimicrobial activity and anti-inflammatory.

Design, synthesis, biological evaluation, and bio-computational modeling of imidazo, thieno, pyrimidopyrimidine, pyrimidodiazepene, and motifs as antimicrobial agents

Abstract In the drug chemistry industry, synthesizing a talented exclusive series of aza-polyheterocyclic compounds was crucial. Aminopyrimidine nucleus reacted with two equivalents of benzaldehyde in the presence of KOH as a starting material to bring about imidazopyrimidine derivative, which experienced intermolecular cyclization using carbon disulfide, Br2/AcOH, and/or HNO2 to produce thiazole, thieno, and/or nitro pyrimidine derivative, respectively. Accordingly, the nucleus of Aminopyrimidine was prepared and used to develop the novel polyheterocyclic systems acylated with two moles of succinic anhydride to furnish the imidazolopyrimidine derivative. Benzylidene ethyl cyanoacetate and aminopyrimidine undergo (3 + 4) intermolecular cycloaddition 1,3 H shift followed by hydrolysis and after CO2 evolution provided diazepine derivative. The diazepine derivative was attained due to the cyclo-condensation of the starting material and acetylacetone. Moreover, the structure of the novel synthesized compound series was exploited and verified via spectroscopic approaches. The synthesized series were tested for antimicrobial activity against gram-positive and gram-negative bacterial strains and antifungal activity. The thienopyrimidine derivatives and diazepine exhibited unusual antimicrobial activity. Furthermore, the molecular docking studies confirmed the biological studies with Molecular Operating Environment and petro orisis molinspiration studies, which proved the activity of compounds 4, 5, 7, 10, 13, and 16.

Optimization of biodiesel yield from non-food karanja seed oil: Characterization and assessment of fuel properties

In the present research work, a non-conventional oil i.e., karanja (Pongamia pinnata L.) seed oil was selected to synthesize biodiesel through base catalyzed transesterification reaction. To minimize the FFA (free fatty acid) value of oil, esterification of oil using H2SO4 was carried out before the transesterification. The esterified oil was then subjected to transesterification with methanol in the presence of KOH, yielding karanja oil methyl esters (KOMEs) along with glycerol as a side-product. The transesterification was carried out under optimized reaction parameters such as alcohol to oil molar ratio of 6:1, temperature of 60 °C, KOH concentration of 1.00%, reaction time of 120 min, stirring rate of 750 rpm and maximum KOMEs yield of 95.4% was achieved. Different functional groups in KOMEs were traced via FTIR whereas GC-MS profiling was investigated to characterize different fatty acids in KOMEs. Moreover, fuel characteristics of KOMEs were determined and matched with standards. The findings of this research work support the use of Pongamia pinnata seed oil as a viable non-conventional/non-food oil feedstock for production of good quality biodiesel with value-added perspectives.

Design, Synthesis, Molecular Docking, Antitubercular, Antimicrobial and Antioxidant Studies of Some Novel 3-(((1H-Benzo[d]imidazol-2- yl)methyl)thio)-5H-[1,2,4] Triazino[5,6-b]indole Derivatives

A series of novel 3-(((1H-benzo[d]imidazol-2-yl)methyl)thio)-5H-[1,2,4]triazino[5,6-b]indole derivatives (3a-3j) were synthesized by reacting different substituted 5H-[1,2,4]triazino[5,6-b]indole-3-thiols with substituted (2-chloromethyl)-1H-benzo(d)imidazoles in the presence of KOH and water in good yields. The structures of the newly synthesized compounds were confirmed by spectroscopic techniques such as 1H-NMR, 13C-NMR, IR and mass spectrometry. The in-vitro antitubercular activity of the synthesized compounds was evaluated against Mycobacterium tuberculosis (Mtb) H37Rv (ATCC 27294) using MABA (Microplate Alamar Blue Assay) method. Compounds 3b, 3c, and 3i showed good antitubercular activity against Mtb with MIC value of 6.25 ± 0.00 μg/mL. Also, the in-vitro antimicrobial activities of the compounds were evaluated against various bacterial and fungal strains using the two-fold serial dilution technique and most of the compounds exhibited moderate activities with MIC values in the range of 63.33 ± 1.44 to >500 ????g/mL against the tested microorganisms. The compounds (3a-3j) were also tested for their in-vitro antioxidant activities by DPPH radical scavenging activity method and among the series, compounds 3e, 3a, and 3g exhibited strong antioxidant activity with IC50 values of 10.85 ± 0.05, 12.18 ± 0.13 and 12.57 ± 0.17????g/mL respectively compared to the standard ascorbic acid (IC50 value, 5.85 ± 0.04 ????g/mL). Further, molecular docking studies were performed to investigate the binding affinities as well as the interaction of these compounds with Mtb InhA target protein. In-silico ADME predictions showed that all the synthesized compounds have drug-like properties and exhibited good oral bioavailability.

Synthesis, Computational Studies, Antioxidant and Anti-Inflammatory Bio-Evaluation of 2,5-Disubstituted-1,3,4-Oxadiazole Derivatives.

The 1,3,4-oxadiazole derivatives Ox-6a-f have been synthesized by incorporating flurbiprofen moiety with the aim to explore the potential of target molecules to decrease the oxidative stress. The title compounds Ox-6a-f were prepared by simple reactions in which a flurbiprofen -COOH group was esterified with methanol in an acid-catalyzed medium, which was then reacted with hydrazine to afford the corresponding hydrazide. The acid hydrazide was then cyclized into 1,3,4-oxadiazole-2-thiol by reacting with CS2 in the presence of KOH. The title compounds Ox-6a-f were synthesized by the reaction of an -SH group with various alkyl/aryl chlorides, which involves an S-alkylation reaction. The structures of the synthesized Ox-6a-f derivatives were ascertained by spectroscopic data. The in silico molecular docking was performed against target proteins cyclooxygenase-2 COX-2 (PDBID 5KIR) and cyclooxygenase-1 COX-1 (PDBID 6Y3C) to determine the binding affinity of the synthesized compounds with these structures. It has been inferred that most of the synthesized compounds bind well with an active binding site of 5KIR compared to 6Y3C, and especially compound Ox-6f showed excellent binding affinity (7.70 kcal/mol) among all synthesized compounds Ox-6a-f. The molecular dynamic (MD) simulation has also been performed to check the stability of docking complexes of ligands with COX-2 by determining their root mean square deviation and root mean square fluctuation. Little fluctuation was observed in case of Ox-6f, which forms the most stable complex with COX-2. The comprehensive antioxidant potential of the synthesized compounds has been evaluated by determining their free radical scavenging activity, including DPPH, OH, nitric oxide (NO), and iron chelation assay. The derivative Ox-6f showed promising results with 80.23% radical scavenging potential at a dose of 100 µg/mL while ascorbic acid exhibited 87.72% inhibition at the same dose. The anti-inflammatory activity of the final products has also been performed, and inflammatory markers were assayed, such as a thiobarbituric acid-reducing substance, nitric oxide, interleukin-6 (IL-6), and COX-2. The derivatives Ox-6d and Ox-6f displayed higher anti-inflammatory activity, exhibiting 70.56% and 74.16% activity, respectively. The results were compared with standard ibuprofen, which showed 84.31% activity at the same dose, 200 µg/mL. The anti-inflammatory potential has been performed by following the carrageen-induced hind paw edema model, and results showed that derivative Ox-6f exhibited 79.83% reduction in edema volume compared to standard ibuprofen, which reduced 84.31% edema volume. As dry lab and wet lab results confirm each other, it has been deduced that derivative Ox-6f may serve as the lead structure to design potent compounds to address oxidative stress.

Superoxide Radical Formed on the TiO2 Surface Produced from Ti(OiPr)4 Exposed to H2O2/KOH

In this study, the superoxide radical O2•− formed by treating Ti(OR)4 (R = iPr, nBu) with H2O2 in the presence of KOH was detected in the EPR spectra. The g-tensor of this radical differs from the typical values reported for a superoxide on various TiO2 surfaces. On the other hand, similar g-tensor components g||(zz = 2.10 ± 0.01, g⊥ = 2.005 ± 0.003 assigned to the O2•− were previously observed for radicals in aqueous solutions in the presence of K2O, alkaline solutions of DMSO, and water/DMSO mixtures. A common factor in all these systems is the presence of alkali ions. However, there was no structural support for the possible interaction of alkali ions with a superoxide in these systems. The use of multifrequency pulsed EPR techniques in this work revealed the stabilization of the O2•− near the K+ ion and its involvement in a strong hydrogen bond with the surface. These findings are consistent with the features previously reported for superoxides on a Na pre-covered MgO surface. Interactions with a closely located 23Na and a strongly coupled 1H proton were also seen in the HYSCORE spectra but assigned to two different superoxides with various gzz values presented in the sample.

From Ce(OH)3 to Nanoscaled CeO2: Identification and Crystal Structure of a Cerium Oxyhydroxide Intermediate Phase

Cerium oxide is a pivotal compound in catalysis, both as a support and as an active phase. However, its fine features, such as the Ce(III) to Ce(IV) ratio, strongly depend on the protocol used to prepare it. While the literature contains tens of protocols to prepare cerium oxide nanoparticles from Ce(III) precursors, there is still an open question regarding the time at which the cerium oxidation occurs and the role of hydroxide phases in this process. This article identifies an oxyhydroxide phase of Ce(IV) as a key intermediate and proposes a crystal structure for it. For this purpose, phase-pure cerium trihydroxide (Ce(OH)3) nanorods (<20 nm) were first prepared by hydrothermal treatment of a cerium nitrate salt (Ce(NO3)3·6H2O) in the presence of KOH. Aging of this phase in air was monitored by X-ray absorption spectroscopy, which confirmed the formation of an intermediate Ce(IV) crystalline compound, unreferenced so far. Based on X-ray and neutron powder diffraction experiments combined with DFT calculations, we propose that this new phase is a cerium oxyhydroxide of the chemical formula CeO(OH)2, for which a structural model is proposed. Thermodiffraction experiments finally established that this compound is an observable intermediate in the synthesis of cerium dioxide CeO2 by calcination of Ce(OH)3 in air.

A Catecholaldimine-Based NiII-Complex as an Effective Catalyst for the Direct Conversion of Alcohols to trans-Cinnamonitriles and Aldehydes.

A nickel(II) complex [Ni(HL)2] 1 was synthesized by treatment of a new catecholaldimine-based ligand with NiCl2·6H2O in methanol at room temperature. Complex 1 showed excellent catalytic activity where aromatic and heterocyclic alcohols were rapidly converted into trans-cinnamonitrile in a one-pot manner via oxidative olefination in the presence of KOH. The potential of the disclosed catalyst and the results obtained for the direct conversion of alcohols to two different functionalities (trans-cinnamonitrile and aldehydes) are well supported by DFT studies.

Synthesis and Assessment of the Cytotoxic Effects of Some Novel Biginelli 3,4-Dihydropyrmidine-2-(1H) One Derivatives Containing 2-Mercapto-3-Phenyl-4(3H)-Quinazolinone

In the present study, a new series of 3,4- dihydropyrmidine2-(1 H) one derivatives(4a-f) which linked to 2-mercapto-3-phenyl-4(3H)-quinazolinone were synthesized by using the nucleophilic substitution reaction of 2-mercapto-3-phenyl-4(3H)-quinazolinone (1) and an appropriate 6-bromomethyl-3,4- dihydropyrmidine2-(1 H) one (3a-f) in the presence of KOH as a base and in CH3CN as solvent. The chemical structures of the synthesized compounds were confirmed by means of IR, 1H-NMR, 13C-NMR, Mass spectroscopy, and Elemental analysis. The cytotoxicity of the newly synthesized compounds was evaluated in vitro against the human breast cancer (MCF-7) cell line and human colon cancer cell line (HT-29) based on the results of the MTT assay. Our results indicated that compound 4b exerted the most cytotoxic effect in the two cell lines and the IC50 values were (4.25 ± 0.16 μM) for MCF-7 cell lines and (12.11 ± 0.76 μM) for HT-29 cell lines. Also, compound 4b induced apoptosis more than other compounds in the two cell lines. Therefore, compound 4b may be a potential anticancer agent.

Hydrothermal Liquefaction of Pinewood Sawdust: Influence of Reaction Atmosphere

Hydrothermal liquefaction (HTL) is a thermochemical process for production of biocrude oils, commonly from wet biomass under inert atmosphere (N2). Influence of reaction atmosphere on HTL of pinewood sawdust was investigated in this work, at 300 °C for 60 min with the presence of KOH or H2SO4 catalyst under N2, H2, and O2 atmosphere, respectively. Very interestingly, the reaction atmosphere showed significant influence on both products distribution and properties of the biocrude oils. Generally, H2 atmosphere enhanced biomass degradation in the presence of either KOH or H2SO4 catalyst, producing the highest biocrude oil yield, lowest solid residue yield, and the best oil quality in terms of total acid number (TAN), viscosity and average molecular weights (Mn, Mw). Whereas the HTL in O2 atmosphere showed the poorest performance in terms of yields and properties of biocrude oils. The highest quality of biocrude oil was produced using KOH catalyst in H2 atmosphere with the maximum biocrude yield (approx. 34 wt.%) and the highest energy recovery (ER) in biocrude (ER = 73.14%). The measured properties of the oil are as follows: TAN = 40.2 mg KOH/g, viscosity = 51.2 cp, Mn = 470 g/mol, Mw = 767 g/mol. In addition, the biocrude oils produced in H2 atmosphere contain more light oil (naphtha) fraction (23.9 wt.% with KOH and 16.5 wt.% with H2SO4) with lower boiling points, while those generated in O2 atmosphere have more carboxylic acid compounds.