Active Functional Groups Research Articles

Facile fabrication of SiC/ZnO composite and its enhanced sensitivity for detection of NO

Zinc oxide (ZnO) is an attractive material for gas sensors, and various ZnO-based sensors have been developed to detect gas pollution. In this work, a series of SiC/ZnO composites were fabricated by incorporating silicon carbide nanocrystals (SiC NCs) into ZnO microspheres by a grinding method. The SiC/ZnO composite exhibited a significantly enhanced gas sensitivity response toward NO gas in comparison to ZnO. The test revealed that the response of the composite was 251.1 for 100 ppm of nitrogen monoxide (NO), and the detection limit was as low as 100 ppb. Through spectral and comparative analyses, it has been indicated that the active functional groups of the SiC NCs have a substantial impact on the detection of NO, and the corresponding mechanism is studied and discussed. This work offers a simple strategy for the fabrication of SiC/ZnO material with enhanced sensitivity in sensing applications.

Low-Cost and High-Strength Soybean Meal Adhesives Modified by Tannin–Phenol–Formaldehyde Resin

Wood adhesive is very important to the quality of wood-based panels in the forest product industry. Researchers are currently focused on developing green and environmentally friendly adhesives using biomass materials. Soybean meal (SM), a cheap and high-protein byproduct from soybean processing, is considered a green biomaterial resource for adhesive production. In this study, SM was modified using urea and sodium hydroxide as denaturants, and two cross-linking agents were prepared to incorporate into the soybean meal adhesive for bonding reactions. Sodium hydroxide added to soybean protein caused structural damage to the protein structure, which allowed the peptide chains to unfold extensively, forming a low-molecular-weight peptide mixture with a good size distribution and exposing numerous active functional groups for cross-linking with the tannin–phenol–formaldehyde resin (TR) and wood. Adding the epoxy resin CA and TR enabled the cross-linking agents to react with the active functional groups on proteins, forming a cross-linked network structure. As a result, the adhesive’s strength, residual rate, and solid content were improved.

Cu/TiO2 adsorbents modified by air plasma for adsorption–oxidation of H2S

In this study, non-thermal plasma (NTP) was employed to modify the Cu/TiO2 adsorbent to efficiently purify H2S in low-temperature and micro-oxygen environments. The effects of Cu loading amounts and atmospheres of NTP treatment on the adsorption-oxidation performance of the adsorbents were investigated. The NTP modification successfully boosted the H2S removal capacity to varying degrees, and the optimized adsorbent treated by air plasma (Cu/TiO2-Air) attained the best H2S breakthrough capacity of 113.29 mg H2S/gadsorbent, which was almost 5 times higher than that of the adsorbent without NTP modification. Further studies demonstrated that the superior performance of Cu/TiO2-Air was attributed to increased mesoporous volume, more exposure of active sites (CuO) and functional groups (amino groups and hydroxyl groups), enhanced Ti-O-Cu interaction, and the favorable ratio of active oxygen species. Additionally, the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results indicated the main reason for the deactivation was the consumption of the active components (CuO) and the agglomeration of reaction products (CuS and SO42−) occupying the active sites on the surface and the inner pores of the adsorbents.

Enhancement of Poly-L-lactic acid stents through polydopamine coating: Boosting endothelialization and suppressing inflammation

The utilization of Poly-L-lactic acid (PLLA) as a biodegradable material for biovascular scaffolds (BVS) stems from its superior mechanical attributes, biodegradability, and biocompatibility. However, PLLA's challenges, such as its lack of active surface functional groups and high hydrophobicity, impede endothelial cells' (ECs) attachment and growth. These factors subsequently amplify the risk of thrombosis and restenosis in PLLA implants. To counteract this problem, we've adapted the polydopamine (PDA) coating technique, a technique commonly used for metal stents. This method has demonstrated potential for promoting EC adhesion and proliferation on PLLA surfaces. Our study involved the application of PDA coating to PLLA, which resulted in improved EC attachment and proliferation while simultaneously inhibiting macrophage activation and the release of the inflammatory factor TNF-α. Additionally, the reactive functional groups on the PDA-coated surface provide a reactive platform for immobilizing therapeutic molecules onto PLLA, thereby further enhancing the biocompatibility of PLLA cardiovascular stents.

Iron‐Catalyzed Alkenylzincation of Internal Alkynes†

Comprehensive SummaryThe alkenylzincation of internal alkynes is an effective method for the synthesis of multi‐substituted conjugated dienes; however, the current catalytic systems for this reaction are limited in terms of substrate scope and selectivity control, which restricts its practical applications. Herein, we report the first iron‐catalyzed alkenylzincation of internal alkynes, which features mild conditions, simple operation, broad substrate scope (including aryl/alkyl, diaryl, and dialkyl acetylenes), excellent functional group tolerance (tolerating highly active functional groups such as ester, methylthio, amide, sulfonyl, cyano, etc.), and high activity (with a turnover number of up to 11500, the highest record for carbometallation reactions). Notably, the catalytic system described in this article also realized the highly selective vinylzincation of unfunctionalized internal alkynes as well as the alkenylzincation of unsymmetrical diarylacetylenes and dialkyl acetylenes, which have not been achieved with other catalytic systems reported in the literatures. The current study provides a highly selective access to synthetically important multi‐substituted conjugated dienes.

Synergistic adsorption and photocatalysis reduction of uranium by UiO-66 (Ce)-CdS/PEI-modified chitosan composite sponge

Uranium is a critical element of the nuclear industry, and while extracting it from seawater is considered the most promising way to meet the growing demand for uranium, there are still some problems that still need to be solved. This work designed a UiO-66(Ce)-CdS/PEI-modified chitosan composite sponge (USPS) with an adsorption-photocatalytic synergistic effect to extract uranium efficiently. On the one hand, the drawback that the powder material is difficult to be recycled is solved. On the other hand, the uranium extraction capacity of the substrate sponge is improved. Compared with the unmodified PCS sponge, the uranium extraction capacity of the USPS-4 composite sponge is 1.63 fold higher than that of the PCS sponge. In addition, the USPS-4 composite sponge exhibits excellent selectivity and regenerability. The mechanism of uranium extraction can be summarized as the coordination chelation of uranium with active functional groups in the adsorption process and the reduction of hexavalent uranium by photogenerated electrons in the photocatalytic process. This study provides a new strategy for designing and preparing a novel material with high uranium extraction performance, easy separation, and recovery.

Preparation, properties and applications of porous hydrogels containing thiol groups for heavy metal removal

A novel porous hydrogel adsorption material, called PAM/PAA/PDMTM gel, has been developed for the removal of heavy metal ions in complex systems. The gel is composed of polyacrylamide, polyacrylic acid, and poly(2,4-dimercapto-6-mercaptopropenyl-1,3,5-triazine) monomer. This hydrogel material features a large pore structure, abundant active functional groups, high swelling properties, good thermal stability, and remarkable regeneration ability. More importantly, the hydrogels contain a variety of active groups, they show good complex adsorption properties for heavy metals. The PAM/PAA/PDMTM gel demonstrated excellent adsorption performance, with the maximum adsorption capacity of Cu2+, Cd2+ and Pb2+ reaching 92.33, 110.08 and 200.97 mg g−1 (pH 5, 298 K), respectively. And the adsorption was in accord with the pseudo-second-order model and Langmuir model. Notably, the PAM/PAA/PDMTM gel also demonstrated remarkable adsorption capacity for Pb even in soil, making it an efficient adsorption material for removing heavy metals from both water and soil samples.

The Effect of Organic Matter from Sewage Sludge as an Interfacial Layer on the Surface of Nano-Al and Fluoride.

Due to its high reactivity, the nano aluminum particle (n-Al) has attracted more attention in energetic materials but is easily oxidized during processing. In order to realize sewage sludge (SS) resource and n-Al coating, the organic matter was extracted from SS, using the deep eutectic solvent method due to its strong dissolving capacity, and then the organic matter was pretreated by ball milling, which was used as an interfacial layer between n-Al and fluoride. It was found that organic matter was successfully extracted from SS. The main organic matter is proteins. The ball milling method can effectively destroy the secondary structure of proteins to release more active functional groups. During the pretreatment, the Maillard reaction broke the proteins structure to form more active low molecular weight compounds. It was confirmed that n-Al can be coated by PBSP under mild conditions to form a uniform core-shell structure. PFOA can effectively coat the n-Al@PBSP to form n-Al@PBSP/PFOA, which can enhance the combustion of n-Al. The gas phase flame temperature can notably improve to 2892 K. The reaction mechanism between n-Al and coating was analyzed. The results could help SS treatment and provide new insights for n-Al coating and SS-based organic matter recovery and utilization.

Rational design of MOF@COF composites with multi-site functional groups for enhanced elimination of U(VI) from aqueous solution

Both environment and human beings were menaced by the widespread application of radioactive uranium, high-performance and effective elimination of uranium from wastewater is of important meaning for development of environmental sustainability in the future. In this study, the water-stable MOF material and the highly crystalline COF were compounded by a mild hydrothermal strategy, which achieved efficient removal of U(VI) through the synergistic effect. The composites showed the characteristics of both COFs and MOFs, which will possess higher stability, larger surface area and faster adsorption efficiency that cannot be carried out by a single component. Batch experiments and characterizations (SEM, TEM, XRD, FT-IR, BET, XPS, etc.) indicated that UiO-66-NH2@LZU1 had more stable and multi-layer pore structure and rich active functional groups. The Langmuir model and the pseudo-second-order kinetics fitting was more suitable for the U(VI) elimination process. The greatest uranium adsorbing capacity of UiO-66-NH2@LZU1 (180.4 mg g−1) was observed to exceed the UiO-66-NH2 (108.8 mg g−1) and COF-LZU1 (65.8 mg g−1), which reached the excellent hybrid effects. Furthermore, FT-IR and XPS analyses confirmed that the most nitrogen-containing group from COF-LZU1 and oxygen-containing group of UiO-66-NH2 could be combined with U(VI). In addition, electrostatic interaction was also a mechanism during the removal process. This work displayed that UiO-66-NH2@LZU1 was a prospective hybrid material for radioactive waste remediation. The compound method and application mentioned in this work had provided a theoretical basis for designing and developing multi-functional composite adsorbents, which contributed to the development of new materials for radioactive wastewater treatment technologies.

Microstructure analysis of graphene oxide synthesized from corn cobs waste

Graphene oxide is one carbon-based material decorated by oxygen functional group that has been applied in various field. Active oxygen functional group allows graphene oxide served as precursor for many applications including DSSC, Field Effect Transistor, LED, and Transparent Conductive Film. Unfortunately, high cost of pure raw material inhibits the wide application of graphene oxide. Corn cobs is one of highly produced waste from agricultural activity that become an unsolved environmental problem. Meanwhile, high content of carbon material in corn cob allows it to be a potential carbon source for graphene oxide synthesis. In this report the synthesis of graphene oxide from corn cobs using modified hummers method is discussed. As synthesized sample was analysed using FTIR, XRD, and SEM to confirm the successful of graphene oxide form corn cobs.

Decorated xanthan gum/alginate mingled hydrogel beads@La(III)-MOFs@reduced graphene oxide@graphene quantum dots nanohybrid for adsorptive capture and recovery of U(VI)

Uranium as an example of radionuclide toxic heavy metal has shown serious impacts on human and living systems causing well-known sever diseases and therefore, proper attention should be directed and given to safely store and remove uranium hazardous species from the environment especially water resources by finding effective approaches for remediation and capturing uranium from water or wastewater. Therefore, the present investigation is designed to fabricating and combining of xanthan gum and alginate mingled hydrogel beads with reduced graphene oxide (rGO)/graphene quantum dots (GQDs) and lanthanum 1,4-benzene di-carboxylate (La-MOFs) in a single nanocomposite (La-BDC/rGO/GQDs@mingled hydrogel) for direct application in adsorptive capturing of U(VI) from water. The assembled nanocomposite was found into crystalline structure as well as characterized and detected with multiple correlated active functional groups to the constituting units from the FT-IR analysis, while the HR-TEM analysis showed uniformly distributed particles with 25.3 nm as the average nanocomposite size. The effectiveness behavior of La-BDC/rGO/GQDs@mingled hydrogel nanocomposite in adsorptive capturing of uranyl ions (50 and 100 mg/L) was explored and optimized in a number of experimental conditions and revealed to the optimum pH = 7.12, nanocomposite dose = 20 mg and reaction time = 30 min. The adsorptive capture interaction of U(VI) by La-BDC/rGO/GQDs@mingled hydrogel nanocomposite perfectly fitted with the linear and nonlinear pseudo-second order expressions giving 0.96 and 0.93 as well as the linear and nonlinear Freundlich isotherm expressions yielded 0.997 and 0.997 correlation factors, respectively. The computed thermodynamic parameters provided good evidence for the endothermic capture type of U(VI) interaction with La-BDC/GQDs-rGO@mingled hydrogel. The nanocomposite was subjected to more than three regeneration processes with satisfactory results. Finally, La-BDC/rGO/GQDs@mingled hydrogel nanocomposite achieved excellent capture percentage of U(VI) from sea, tap and wastewaters providing 91.19 %, 90.78 % and 91.53 % from 100 mg/L concentration to deliver a direct confirmation for its potential superior performance in adsorptive capturing of U(VI) from contaminated waters.

Stable and highly efficient HMDS terminated m-Cresol inhibitor for inhibiting coal spontaneous combustion

A stable and highly efficient 1, 1, 3, 3, 3-hexamethyldisilazane (HMDS) terminated m-Cresol inhibitor was synthesized based on the protection-deprotection strategy. The inhibitory effect of HMDS terminated m-Cresol inhibitor on spontaneous combustion of lignite was explored through temperature-programmed oxidation tests, in-situ infrared analysis and thermogravimetric analysis. Results show that, the oxidation of active phenolic hydroxyl groups in the m-Cresol inhibitor can be hindered by the protection of HMDS. After encountering coal, the HMDS terminated inhibitor can be gradually deprotected to regenerate the m-Cresol inhibitor that contains massive active phenolic hydroxyl groups, thus improving the chemical inhibition efficiency of coal spontaneous combustion. For the coal sample inhibited with HMDS terminated m-Cresol inhibitor, the initial contents of the active functional groups are lower and more stable during heating, and the inhibition rate reaches 70% at 130 °C. Moreover, the crossing-point temperature rises by 32.4 °C–181.2 °C. The activation energy increases by 11 kJ/mol and 18 kJ/mol at below and above 130 °C respectively. The peak temperature at maximum weight loss rate rises by 65 °C–431.2 °C, and the corresponding residual carbon rate increased by 31.3%–61.6%. The inhibition mechanism of the HMDS terminated m-Cresol inhibitor on coal spontaneous combustion was deduced.

Fabrication of Gelatin-Derived Gel Electrolyte Using Deep Eutectic Solvents through In Situ Derivatization and Crosslinking Strategy for Supercapacitors and Flexible Sensors.

The facile fabrication of gel polymer electrolytes is crucial to the development of flexible electronics, and the use of natural polymers as sources has obtained great attention due to their abundant, low-cost, biodegradable, easy modification, and biocompatible features. In this article, a facile fabrication protocol to engineer gelatin into gel electrolytes was developed by taking the advantages of both deep eutectic solvent (DES) (including its good solubility to gelatin and satisfactory electrochemical properties) and rich active functional groups of gelatin, through in situ derivatization and crosslinking strategy. A double-crosslinked DES gel electrolyte was prepared with the dissolution of gelatin in choline chloride and alcohol-based DES and a further crosslinking with Fe3+ ions. The obtained DES gel presented outstanding mechanical properties, excellent ionic conductivity (up to 101-102 mS/cm), a wide operating temperature range (-40 to 80 °C), satisfactory self-healing property, and good degradability. Moreover, the obtained DES gel electrolyte was successfully applied to supercapacitors and flexible sensors, showing excellent electrochemical performance and strain-response properties. In a word, our study provides a facile protocol to engineer gelatin into gel electrolytes by using deep eutectic solvent, showing significant insights into the design and preparation of sustainable gel polymer electrolytes and having great application potential in next-generation high-performance flexible electronics.

Low dielectric constant and high thermal stability of liquid crystal epoxy polymers based on functionalized poly(phenylene oxide)

Epoxy resins exhibit poor thermal and dielectric properties because of the disordered entanglement of the chain segments and a large number of hydroxyl groups generated after curing by diamine curing agents. Herein, to prepare high-Tg and low-dielectric epoxy thermosets, two functionalized poly(phenylene oxide) (PPOs) were synthesized by redistribution and esterification reactions and used as curing agents to cure liquid crystal epoxy (t-BPDGE). The modified PPOs (TMPA and TMBPA) contain six active ester functional groups, which not only improved the compatibility and the degree of cross-linking of the PPOs with the epoxy monomers but also avoided the generation of hydroxyl groups after curing. The curing mechanism was investigated using TBB cured glycidyl phenyl ether as a model reaction, and the effects of TMPA and TMBPA on the curing behavior and performances were also studied. Due to the ordered arrangement of the liquid crystal epoxy resins and the presence of PPOs, the overall performances of PPOs-based/t-BPDGE are significantly improved. Specifically, the results showed that TMPA/t-BPDGE possessed a high glass transition temperature (Tg) of 199.47 °C and a char rate of 21.84%, which was 77.09 °C and 3.63 times higher than that of the DDM/t-BPDGE, respectively. Moreover, TMPA/t-BPDGE exhibited a lower moisture absorption (0.23%), dielectric constant and loss (2.94 and 0.00815 at 1 GHz) compared to the DDM/t-BPDGE (0.48%, 3.95 and 0.01898, respectively). The findings provide a new design strategy for preparing high-Tg and low-dielectric epoxy thermosets.

Ultrathin reticulated carbon material as a metal-free electrocatalyst for oxygen reduction reaction

Development of excellent oxygen reduction reaction (ORR) electrocatalysts for fuel cell cathodes is critical for sustainable commercialization. However, transition metal catalysts produce H2O2 during ORR catalysis, promoting the Fenton reaction, and Pt-based catalysts are expensive and prone to poisoning and inactivation. Therefore, developing metal-free ORR catalysts is critical. Herein, a N, F, and S triple-doped metal-free ORR electrocatalyst, T1P1-950, was synthesized using thiourea and polytetrafluoroethylene via a one-step heat treatment method. T1P1-950 exhibited a graphene-like reticulated structure, and its ORR half-wave potential (E1/2) was 16 mV higher than that of Pt/C in an alkaline medium (0.861 V vs. 0.845 V). In acidic media, the ORR E1/2 of T1P1-950 was 80 mV lower than that of Pt/C (E1/2: 0.751 V vs. 0.831 V). In addition, T1P1-950 was superior to Pt/C in terms of methanol resistance and durability. This can be attributed to the following factors: (1) The catalyst has a network structure similar to that of graphene, which is conducive to the transport of reactive particles in the ORR; (2) the synergistic effect of N, F, and S doping enhances the ORR efficiency of the active sites; and (3) the catalyst has high active functional group and N contents of 6.1% and 7.1%, respectively, which is conducive to the formation of more active sites. In addition, the assembled zinc-air battery also proves that the T1P1-950 has excellent oxygen electrocatalytic performance in practical operation. This study offers a universal technique for producing a broad range of heteroatom-doped ultrathin reticulated carbon materials.

Experimental Study on the Inhibition of Coal Spontaneous Combustion by an Ammonium Polyphosphate/Nitrogenous Composite Inhibitor

ABSTRACT An efficient, environmentally friendly, and economical polyphosphate/nitrogen-containing composite inhibitor (APNI) has been developed to prevent coal spontaneous combustion (CSC) disasters. Using temperature rise experiments during coal spontaneous combustion, mercury pressure experiments, and Fourier transform infrared spectroscopy (FTIR), the samples treated with the APNI were compared with those treated with MgCl2 and NH4H2PO4 inhibitors, and the inhibitory effects of the three inhibitors on CSC were studied. The results showed that the APNI effectively limited the reactions between the coal and oxygen, reduced the amount of CO gas generated, sealed most of the cracks, large pores and mesopores in the coal, and reduced the number of active functional groups in the coal. The APNI was more effective in preventing CSC than MgCl2 and NH4H2PO4.

Carbon steel behavior towards Cucumeropsis mannii shell extract as an ecofriendly green corrosion inhibitor in chloride medium

This study advanced on previous studies by investigating the hardness and tensile strength of carbon steel under different loads after determining the corrosion rate at different temperature, immersion time and corrosion inhibitor concentration in a chloride medium using Cucumeropsis mannii shell extract (CMSE) as an eco-friendly green corrosion inhibitor. The inhibition efficiency was evaluated by weight loss, electrochemical impedance spectroscopy and potentiodynamic polarization techniques. Adsorption behavior and material characterization were investigated. The result revealed maximum inhibition efficiency of 92.2% and 91.2% could be attained by EIS and PDP techniques respectively. The corrosion rate decreases as the inhibitor's concentration increases and vice versa for temperature and immersion time. The Young modulus and hardness of carbon steel decreased at higher load under corrosion attack in the absence of CMSE. The green corrosion inhibitor exhibited a mixed-type with a spontaneous physisorption behavior on carbon steel surface. Material characterization revealed presence of active functional groups in the extract with formation of uniform and pitting corrosion on carbon steel surface. In conclusion, Cucumeropsis mannii shell extract behaved excellently as corrosion inhibitor for carbon steel in chloride solution.

Advances in green materials derived from wood for detecting and removing mercury ions in water

The issue of mercury pollution in environmental remediation has garnered significant attention due to its severe health hazards to humans. Various strategies have been devised to mitigate the impact of toxic mercury ions, including coagulation, ion exchange, adsorption, membrane technology, and electrochemical treatment. Among these approaches, adsorption has emerged as an efficient and widely employed method for the uptake of low concentrations of mercury ions. It offers convenient operation, high removal efficiency, and facile regeneration of the adsorbent. Wood, being the most abundant renewable and sustainable bioresource, has garnered attention as a promising material for treating heavy metal wastewater. This is attributed to its unique physical and chemical characteristics, encompassing hierarchical pores, aligned channels, active functional groups, biodegradability, and cost-effectiveness. However, a comprehensive examination of the cutting-edge applications of wood and wood-derived biopolymers in the detection and removal of mercury ions from wastewater has yet to be undertaken. Consequently, this article presents a chronological overview of recent advancements in materials and structures derived from bulk wood and its constituents, including cellulose, lignin, hemicellulose, and tannin, with a specific focus on their utility in detecting and eliminating mercury from water sources. Subsequently, the most promising techniques and strategies involving wood and wood-derived biopolymers in addressing the predicament of mercury pollution are explored. Furthermore, this piece offers insights into the existing challenges and future prospects concerning environmentally friendly materials derived from wood, aiming to foster the development of cost-effective mercury adsorbents and detection devices.

Experimental investigation on the characteristics of XG/GG/HPAM gel foam and prevention of coal spontaneous combustion

Polymer gel foam shows excellent development potential and application prospects in the prevention of coal spontaneous combustion. To reveal the relationship between the characteristics of gel foam and the prevention of coal spontaneous combustion, XG/GG/HPAM gel foam consisting of polymer xanthan gum (XG), guar gum (GG), and polyacrylamide (HPAM) is prepared. The characteristics of gel foam are investigated in terms of microstructure, viscosity, thermal stability, and film-forming. The effects of gel foam on gas products, characteristic temperature, combustion characteristics parameters, and functional groups during coal oxidation are studied. The results show that polymer delays the foam coarsening and improves the foam stability. XG/GG/HPAM gel foam exhibits a slow foam coarsening process, concentrated bubble diameter distribution, shear-thinning behavior, excellent thermal stability, and film-forming properties. Moreover, the inhibition rate of XG/GG/HPAM gel foam on coal is 43.63% higher than that of ordinary foam. XG/GG/HPAM gel foam effectively improves the apparent activation energy of coal, the maximum weight loss rate of the coal is decreased by 7.55%, and the combustibility, combustion stability, and comprehensive combustion index are diminished by 8.50%, 7.64%, and 10.17%, respectively. Simultaneously, XG/GG/HPAM gel foam reduces the oxidation activity of aliphatic hydrocarbons and oxygen-containing functional groups in coal, blocks the chain reaction, and thus inhibits coal spontaneous combustion. The results provide support for achieving efficient fire prevention performance of gel foam.

Assessing the Dual Use of Red and Yellow Algerian Pomegranate Husks: Natural Antiradical Agents and Low-Cost Biosorbents for Chromium (VI) Removal from Contaminated Waters

The hexavalent chromium (Cr(VI)) released in industrial wastewaters can cause adverse effects on both the environment and human health. This study aimed to investigate the efficiency of the red and yellow pomegranate husk powders (RHP and YHP) as natural quenchers for free radicals and as adsorbents towards Cr(VI) ions. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) surface area analyses were used for biosorbent characterization. The antiradical activity was assessed via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. The adsorption isotherms and kinetics were conducted by the batch method. The results showed the roughness and heterogeneity of the biosorbent surface in the presence of active functional groups. At a dose of 5 mg, both biomasses showed a radical inhibition activity (I) > 85% for DPPH, and (I) > 91% for ABTS. Finally, the isotherms modeling showed that the Langmuir model was the best fit with a maximum adsorption capacity (Qmax) of 413.22 and 403.22 mg/g at pH 2 within 60 min with a solid/liquid ratio (S/L) of 0.5 mg/mL for RHP and YHP, respectively. The kinetic data aligned better with the pseudo-second-order model. This study demonstrates the effectiveness of these biomasses as natural quenchers for free radicals and as biosorbents for Cr(VI) removal from contaminated waters.