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The current study presented a porous liquid (PL) prepared from propylene glycol-based deep eutectic solvent (DES) and hyper-crosslinked polymers (HCP) that are liquids over wide temperature ranges, including ambient temperature. It was shown that the solvent molecules are too large to penetrate the pores of HCP, so the PL is maintained as a suspension with permanent free volume for several months and can absorb large amounts of gases. This study marks the pioneering use of DESs as the liquid medium, replacing ionic liquids due to their closely matched properties. The structural features of both DES and HCP are retained; the increase in CO2 absorption capacity compared to pure DES is due to the presence of a porous solid and is proportional to the amount of solid. The absorbed CO2 amount rises from 1.0105 mmol·g−1 in pure DES to 1.3232, 1.6027, and 1.2168 mmol·g−1 in PL-1, PL-2, and PL-3, respectively. Thermodynamic analysis revealed that the enthalpy of gas absorption allows straightforward regeneration of the PLs in the studied cases. The investigated PLs show great potential as gas absorbents, with the incorporation of just 0.5 wt% of porous polymer material leading to an impressive increase in solvent absorption capacity, up to 59 %.

ZSM-5 zeolite is a multifunctional material highly efficient for adsorbing ions. Our ZSM-5 was synthesized by employing a nucleating gel as a structure-directing agent, followed by homogenization and hydrothermal treatment. The as-prepared ZSM-5 was physicochemically characterized to assess its properties. Next, the as-prepared zeolite was employed as an adsorbent to remove rare earth elements, REEs from synthetic solutions and real phosphogypsum leachate under batch mode operation. As expected, the ZSM-5 adsorbent was discovered to be highly microporous with abundant surface functionalities, which could positively impact REE adsorption. The adsorption data indicated a high affinity between ZSM-5 and all three REEs with rapid kinetics and high adsorption capacities. The modeling study suggested that the adsorption kinetic data were well fitted by Avrami-fractional order, and Liu described the equilibrium data. The maximum adsorption capacity for Ce3+, La3+, and Nd3+ were 99.42 mg g−1, 96.43 mg g−1, 118.10 mg g−1, respectively. Further, the thermodynamic analysis revealed that the interaction between ZSM-5 and Ce3+, La3+, and Nd3+ was favorable, spontaneous, and endothermic. The efficiency of ZSM-5 adsorbent was also studied in recovering several REEs from leachate of phosphogypsum wastes, and the data results proved its potency to do so. The findings reported in this work support the idea that ZSM-5 can be successfully used as an adsorbent to recover REEs from synthetic and real samples.

Three short-alkyl-chain-modified [DBU][TFSI] ionic liquids (ILs) were synthesized and utilized in electrets. The electrets were prepared by mixing a UV-curable polymer with the ionic liquids followed by polymerization while applying an external electric field, thus forming spatially separated anions and cations in the proximity of opposing surfaces of the composite slabs. The immobilized surplus surface charge was measured by periodically engaging the electret with a metal counter electrode plate and detecting the displacement current using a charge amplifier. The results show that electrets based on polymerized [DBU][TFSI] ILs have a separated surface charge density of up to 64 nC × cm⁻², which equals an energy harvesting density of 7.0 nJ × cm⁻². Control measurements repeated after a few days to assess the stability and reproducibility of the systems showed that while charge separation reverses over time to some extent, the polymerized ionic liquid samples are resilient to exposure to atmospheric conditions and could be utilized in this type of energy harvesting scheme.

The development of biomass-based carbon materials has accelerated the research interest in environmental (e.g., adsorbents for wastewater decontamination) and energy applications (e.g., batteries). In this paper, we developed a series of carbon materials (CMs) using a sulfur doping strategy to improve the physicochemical, adsorptive and energy storage properties of the aforementioned CMs. CMs were prepared and optimized using an experimental design denoted as the Box-Behnken design approach with three independent factors (i.e., the temperature of pyrolysis, zinc chloride: biomass ratio and sulfur: biomass ratio), and the responses were evaluated, namely the Specific Surface Area (SBET), mesopore area (AMeso) and micropore area (AMicro) with the help of Nitrogen Physisorption. According to the statistical analysis, under the studied conditions, the responses were mainly influenced by the pyrolysis temperature and ZnCl2 ratio, while the sulfur content did not give rise to any remarkable differences in the selected responses. The physicochemical characterization of the CMs suggested that very high Specific Surface Areas ranging from 1069 to 1925 m2 g−1 were obtained. The sulfur doping resulted in up to 7.33wt.% of sulfur in the CM structure, which yielded CMs with more defects and hydrophilic surfaces. When tested as adsorbents, CMs exhibited a very high adsorption capacity (190 – 356mgg-1), and as anodes, they demonstrated a competitive Lithium Ion Battery (LIB) storage capacity, at least during the first five cycles (306 mAhg-1 at 1C for CM9). However, further studies on long-term cyclability are required to prove the CM materials suitability in LIBs. This work extends our understanding of how pyrolysis and sulfur doping of biomass feedstock affects carbon materials' usability, final characteristics and potential to use in wastewater decontamination by adsorption and as anodes in LIBs.

The need of new electrolytes with wide electrochemical window, good stability and conductivity has promoted novel ionic liquids (ILs) as new solutions for supercapacitors. In this work, four hydrophobic room temperature ionic liquids based on organic superbase-derived cations and Trifluoromethanesulfonimide (TFSI) anion were synthetized. The structures of the novel ILs were analyzed, characterized and their performance as a supercapacitor electrolyte was evaluated. The ILs have high decomposition temperatures of up to 490 °C and electrochemical window up to 4.8 V. It was found that there was an optimal chemical structure providing the best stability and operational potential window coupled with moderate conductivity. The IL with the shortest alkyl chain structure provided the highest conductivity but suffered from instability. The performance of the ILs with longer alkyl chains was hindered by lower conductivities and, in the case of the largest chemical structures, also by reduced cyclic stabilities in open air. However, the ionic liquid with moderate alkyl chain length was found to be stable even in open air providing decent conductivity, which can be utilized in future research to develop other hydrophobic ionic liquids suitable as supercapacitor electrolytes.

Halogenated porous melamine polymers were demonstrated as an efficient catalyst for CO2-epoxide cycloaddition, selectively (>99%) producing C3-C12 cyclic carbonates in excellent yields (upto 99%) under solvent and co-catalyst free conditions. The halogenated polymers outperformed benchmark catalysts incorporating only basic (N-doped carbon, ZIF-8, N-rich melamine polymer) or nucleophilic (TBAB, KI) sites. The superior catalytic performance of these inexpensive polymers was attributed to their unique surface chemistry incorporating abundant, stable basic N sites (amine N and protonated N) and nucleophilic (Cl-, Br- or I-) that enabled simultaneous activation of both epoxide and CO₂ molecule (supported by kinetic and DFT studies). Further, among halogenated polymers a Br- containing material (PMF_Br) presented highest activity owing to its balanced CO₂-philicity and strong nucleophilicity. Most importantly, PMF_Br was robust, reusable and maintained stable performance for continuous production of C3-C4 cyclic carbonate (120 ^oC, 0.3-0.83 h^-1 WHSV_epoxide and 15 bar) in a fixed-bed reactor during 60-190 h TOS.

Hardwood spent mushroom substrate was employed as a carbon precursor to prepare activated biochars using phosphoric acid (H3PO4) as chemical activator. The activation process was carried out using an impregnation ratio of 1 precursor:2 H3PO4; pyrolysis temperatures of 700, 800, and 900 °C; heating rate of 10 °C min−1; and treatment time of 1 h. The specific surface area (SSA) of the biochars reached 975, 1031, and 1215 m2 g−1 for the samples pyrolyzed at 700, 800, and 900 °C, respectively. The percentage of mesopores in their structures was 75.4%, 78.5%, and 82.3% for the samples pyrolyzed at 700, 800, and 900 °C, respectively. Chemical characterization of the biochars indicated disordered carbon structures with the presence of oxygen and phosphorous functional groups on their surfaces. The biochars were successfully tested to adsorb acetaminophen and treat two simulated pharmaceutical effluents composed of organic and inorganic compounds. The kinetic data from adsorption of acetaminophen were fitted to the Avrami fractional-order model, and the equilibrium data was well represented by the Liu isotherm model, attaining a maximum adsorption capacity of 236.8 mg g−1 for the biochar produced at 900 °C. The adsorption process suggests that the pore-filling mechanism mainly dominates the acetaminophen removal, although van der Walls forces are also involved. The biochar produced at 900 °C removed up to 84.7% of the contaminants in the simulated effluents. Regeneration tests using 0.1 M NaOH + 20% EtOH as eluent showed that the biochars could be reused; however, the adsorption capacity was reduced by approximately 50% after three adsorption–desorption cycles.

The present invention provides a method for producing hydrocarbons having 6 to 20 carbon atoms, comprising the steps of: a) providing a feedstock comprising saturated fatty acids, and/or derivatives thereof; b) deoxygenating the feedstock in the presence of a metal free hydrogenation and decarboxylation catalyst under low-pressure hydrothermal conditions, wherein the temperature is in the range 350-400 °C and the pressure is in the range 10-30 bar; and wherein the catalyst is a heteroatom-doped carbon material. Furthermore, there is provided a system for preforming the method in a single reactor (R) system comprises a bed of a carbon catalyst facilitating simultaneous hydrogenation and decarboxylation

To produce chitosan is an interesting research. Chitosan is an important polysaccharide in terms of its various applications in industries and is produced from chitin, an abundant biopolymer in crustacean shell biomass wastes. Traditional processes for chitosan manufacture are commonly based on highly concentrated alkaline or acid solutions which are, however, severely eroding and harmful to the environment. In this study, we have described a ‘greener’ method using 1-ethyl-3-methylimidazolium acetate, [Emim][OAc] ionic liquid (IL), for decrystallization of shrimp crystalline chitin flakes followed by a microwave-mediated NaOH or tetrabutylammonium hydroxide, [TBA][OH], solution-based deacetylation for chitosan production. The decrease in crystallinity in IL pre-treated chitin was confirmed by XRD and SEM analysis which subsequently benefited chitosan production with up to 85% degree of deacetylation (%DDA) in shorter time periods (1-2 hours) and lower alkaline concentrations (20-40%). The %DDA in chitin/chitosan was estimated via FT-IR and NMR analysis. Notably, we could regenerate the ionic liquids: in case of [Emim][OAc] 97 wt.% and in case of [TBA][OH] 83 wt.% could be reused. Roles of ionic liquids in the process were discussed. Molecular dynamics (MD) simulations showed the roles of [TBA]+ cations in the molecular driving forces of [TBA][OH]-induced deacetylation mechanism. The strategy promises a sustainable and milder reaction approach to the existing highly corrosive alkaline- or acid-involved processes for chitosan production.

For the first time, a tandem catalytic material, 5 wt. % Pd/NbOPO₄, was utilized in the depolymerization of wood in supercritical ethanol under hydrogen atmosphere. The experiments were conducted under various conditions, with fresh, and acetone extracted birch. A comprehensive analysis was performed to elucidate the dissolution efficiency and achieved product distribution. The results indicated that with fresh birch, 34 wt. % of lignin monomer yield with 84 wt. % delignification efficiency were obtained while with extracted wood, 35 wt. % of lignin monomer yield with 78 wt. % delignification efficiency were achieved. The total lignin monomer content extracted from the fresh birch is composed of 76.9 wt. % of dimethoxyphenols and 16.5 wt. % with the guaiacol structure. Major lignin monomer product was homosyringaldehyde (61.9 wt. %). With extracted wood, 93.2 wt. % of dimethoxyphenols (63.6 wt. % homosyringaldehyde) and 6.8 wt. % of guaiacol-monomers were achieved. It was concluded that the depolymerization occurred via breaking of the ether bonds in lignin, including ether hydrolysis by Lewis acid sites over the solid acid catalyst and with subsequent deoxygenation of monophenols over Pd. In addition, an extraction process was proposed to extract the aromatic fraction from the obtained biocrude.