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This study presents a novel laser processing technique in a liquid media to enhance the surface mechanical properties of a material, by thermal impact and micro-alloying at the subsurface level. An aqueous solution of nickel acetate (15% wt.) was used as liquid media for laser processing of C45E steel. A pulsed laser TRUMPH Truepulse 556 coupled to a PRECITEC 200 mm focal length optical system, manipulated by a robotic arm, was employed for the under-liquid micro-processing. The study’s novelty lies in the diffusion of nickel in the C45E steel samples, resulting from the addition of nickel acetate to the liquid media. Micro-alloying and phase transformation were achieved up to a 30 µm depth from the surface. The laser micro-processed surface morphology was analysed using optical and scanning electron microscopy. Energy dispersive spectroscopy and X-ray diffraction were used to determine the chemical composition and structural development, respectively. The microstructure refinement was observed, along with the development of nickel-rich compounds at the subsurface level, contributing to an improvement of the micro and nanoscale hardness and elastic modulus (230 GPa). The laser-treated surface exhibited an enhancement of microhardness from 250 to 660 HV0.03 and an improvement of more than 50% in corrosion rate.

Here, potential metallic bipolar plate (BP) materials were manufactured by laser coating NiCr-based alloys with different Ti additions on low carbon steel substrates. The titanium content within the coating varied between 1.5 and 12.5 wt%. Our present study focussed on electrochemically testing the laser cladded samples in a milder solution. The electrolyte used for all of the electrochemical tests consisted of a 0.1 M Na2SO4 solution (acidulated with H2SO4 at pH = 5) with the addition of 0.1 ppm F−. The corrosion resistance properties of the laser-cladded samples was evaluated using an electrochemical protocol, which consisted of the open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) measurements, and potentiodynamic polarization, followed by potentiostatic polarization under simulated proton exchange membrane fuel cell (PEMFC) anodic and cathodic environments for 6 h each. After the samples were subjected to potentiostatic polarization, the EIS measurements and potentiodynamic polarization were repeated. The microstructure and chemical composition of the laser cladded samples were investigated by scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX) analysis.

Laser surface texturing (LST) is a method to obtain micro-structures on the material’s surface for improving tribological performances, wetting tuning, surface treatment, and increasing adhesion. The material selected for LST is AISI 430 ferritic stainless steel, distinguished by the low cost in manufacturing, corrosion resistance, and high strength at elevated temperature. The present study addresses the morphology of new pattern designs (crater array, ellipse, and octagonal shapes). The patterns are applied on the stainless-steel surface by a non-contact method with high quality and precision nanosecond pulsed laser equipment. The investigation of laser parameter influence on thermal affected area and micro-structures is accomplished by morphological and elemental analysis (SEM + EDX). The parameters of the laser micro-patterning have a marked influence on the morphology, creating groove-type sections with different depths and recast material features. From the SEM characterization, the highest level of recast material is observed for concentric octagon LST design. Its application is more recommended for the preparation of the metal surface before hybrid welding. Additionally, the lack of the oxygen element in the case of this design suggests the possible use of the pattern in hybrid joining.

Due to its wide applicability in industry, devising microstructures on the surface of materials can be easily implemented and automated in technological processes. Laser Surface Texturing (LST) is applied to modify the chemical composition, morphology, and roughness of surfaces (wettability), cleaning (remove contaminants), reducing internal stresses of metals (hardening, tempering), surface energy (polymers, metals), increasing the adhesion (hybrid joining, bioengineering) and decreasing the growth of pathogenic bacteria (bioengineering). This paper is a continuation and extension of our previous studies in laser-assisted texturing of surfaces. Three different patterns (crater array-type C, two ellipses at 90° overlapping with its mirror-type B and 3 concentric octagons-type A) were applied with a nanosecond pulsed laser (active medium Nd: Fiber Diode-pumped) on the surface of a ferritic stainless steel (AISI 430). Micro texturing the surface of a material can modify its wettability behavior. A hydrophobic surface (contact angle greater than 90°) was obtained with different variations depending on the parameters. The analysis performed in this research (surface roughness, wettability) is critical for assessing the surface functionality, characteristics and properties of the stainless steel surface after the LST process. The values of the surface roughness and the contact angle are directly proportional to the number of repetitions and inversely proportional to the speed. Recommendations for the use of different texturing pattern designs are also made.

Carbonaceous nanoscale additives present a pronounced influence on the mechanical properties of both metallic and plastic materials. This paper addresses the fabrication of composite coatings by laser cladding of single-walled carbon nanotubes incorporated by ball milling into a nickel-based powder (NiCrBSiFeC). The coatings were obtained by using the preplaced laser cladding technique on steel substrates. Optical microscopy and SEM microscopy were used to characterise the microstructure refinement of the coatings, and the mechanical behaviour of the coatings has been studied through wear and micro-/nanohardness testing.

4R generation nuclear power plants should work with metallic material of the highest quality, capable to resist in maximum safe conditions for 25-30 years. FeCrAl alloys are capable of such performance, because of the resistance to: oxidation at high temperatures, corrosion, erosion and penetrating radiations in liquid metal environments. In addition, such materials are capable of forming on their surface some oxide layers, textured and self-renewable, with high adhesion to metallic substrates. These properties can be improved by microalloying with metal elements such as Ti, Zr, Y, Hf in amounts of 1 to 3%. These chemical elements have high affinity to oxygen, being able to stabilize the structure of the superficial layer of oxide (alumina) and to increase adhesion to the metallic substrate. The FeCrAl alloys microalloyed with titanium were obtained in a VAR (Vacuum Arc Remelting) equipment in argon atmosphere (99.99% purity). There were obtained three batches microalloyed with 0.5%, 1% and 1.5% titanium, preserving the same Fe-14Cr-5Al metal matrix. In order to determine the chemical composition of the oxide layer and of the sample bulk, the EDAX analysis was performed. Microstructural features were revealed using SEM analysis. The results showed the capacity of the FeCrAl alloy to form oxide layers, with different textures and rich in elements such as Al and Ti. The compositional analysis performed on FeCrAl samples microalloyed with 0.5, 1.0 and 1.5% Ti in the central zone shows a relatively similar composition compared to the technological calculations made, reflecting the homogeneity of the alloy. The microhardness measurements performed on the cross sections of the metallic samples attest values in the range 163-183 HV0.2, falling within the normal range for these materials. These values are influenced by the presence of the alloying elements in the metallic matrix and by the homogeneous arrangement of constituents.

This study reports the obtaining of carbon microspheres through the combined solar pyrolysis and solar physical vapor deposition process of a polypropylene-rich fraction from municipal wastes. A synthesis reactor heated by a 2kW solar furnace (CNRS PROMES solar research facility in Font Romeu, France) has been used for the carbonaceous materials obtaining. The material was characterized in terms of morphology (SEM), chemical composition (EDS) and sorption kinetic behavior towards two model anionic and cationic dyes (methylorange and methylene blue) from aqueous solutions.

This study addresses to the laser welding with active flux (SiO2 + Poly (vinyl alcohol)) for improving the geometrical profile and microstructure of the dissimilar carbon steel – stainless steel joints. The experimental tests were carried out using a TRUMPH 556 pulsed laser and a Precitec YW50 welding head manipulated by a robotic arm. AISI 321 and S235 plates with the dimensions of 50X100X0.5 mm were used as welding specimens. Several fusion lines were made in order to determine the optimal SiO2 / Poly mixing ratio and to highlight the influence of the SiO2 flux on the microstructure. Addition of the active flux results in a more stable welding process and with less plasma plume and a narrower weld bead profile. The samples have been analyzed by optical and electron microscopy showing that SiO2 addition lead to formation of mixed morphology of lathy and skeletal ferrite in the weld zone.

In the case of aircraft jet engine blades reconditioning through cladding, it is critical to obtain a perfect bonding between the cladded layer and the substrate to prevent any loss of material during the engine exploitation, which could lead to critical failure. This paper addresses to the reconditioning of VT3-1 titanium jet engine blades through laser cladding. The experimental laser cladding reconditioning was carried out using an TRUMPH TruPulse 556 laser and a coaxial cladding head manipulated by an 9-axis robotic cell. Pure titanium powder was supplied into the coaxial cladding module for reconstruction of the damaged blade. The reconditioning process was carried out using a spot diameter of 1.8 mm and 800 W laser power at a frequency of 90 Hz. Argon was supplied as shielding gas. The engine blades were cross-sectioned and analyzed by optical and electron microscopy and EDS elemental microanalyses. The main advantages of the laser cladding process are good metallurgical bonding and lower heat input during the reconditioning process compared with other conventional remanufacturing processes.

This paper reports the obtaining of poly (vinyl alcohol) and i-carrageenan blend hydrogels by physical crosslinking (consecutive freeze&ndash, thaw cycles). The two polymers were completely miscible in the weight ratio interval used in this study, as determined by solution viscometry data. Strong interactions through hydrogen bonding and forming of mixed interpolymer crystalline domains were observed, which are responsible for the formation of stable drug release-tunable matrices. The release profiles of three model antibiotic drugs (amoxicillin, tetracycline hydrochloride, and gentamicin sulfate) were assessed in a pH interval between 3 and 7.3. They were found to be strongly dependent on the drug chemistry, mesh size of the hydrogels, swelling mechanism, and pH of the release medium. A decrease of up to 40% in the release rates and up to 10% in the diffusion coefficients of the model drugs was registered with the increase in i-carrageenan content.

Visible light-activated photocatalysts are gaining general importance in advanced methods for removing persistent organic compounds. In this study, two types of composite oxide-metal coatings are obtained on copper substrates through thermal spraying of an aluminum bronze powder with different time-of-flight distances between the spraying nozzle and the substrate (150 and 200 mm). The surfaces of the coatings consist of nanopatterned α-Fe2O3 and CuxO produced by oxidation of the metal phase during the thermal spraying process. The optical band gap energies of the coating assemblies are 2.573 and 2.131 eV, respectively, and the Brunauer–Emmett–Teller (BET) specific surface areas are 4.65 and 4.87 m2 g−1, respectively. The photocatalytic performance of the two types of thermally sprayed coatings in the visible region is studied using methylene blue as a model compound. The coatings present remarkable stability in aqueous environments, good hydrophilicity, high photodegradation rates (0.20–0.26 h−1), high organic dye mineralization efficiencies (75.69 and 92.36%) and unaltered methylene blue removal efficiencies during three successive 12 h photodegradation cycles (91–99.60%).

Single carbon nanotubes were synthesized through a physical vapor deposition method, using concentrated solar radiation as means of vaporization and promoting the formation of carbonaceous plasma plume. A novel catalyst, containing multiple hybrid ceramic/metal phases has been obtained through flame spraying. In conjunction with this catalyst, good quality nanomaterials, such as long single-walled nanotubes and nanoparticles have been obtained and characterized by both morphological (SEM, TEM) as well as structural means on analysis (XRD, FTIR). A mild oxidation of the carbonaceous phase has been reported, which could prove useful in applications in conjunction with metals or hydrophilic polymers as potential matrices for nanocomposites obtaining.

Composite finger-jointed spruce and oak wood panels have been thermally treated under standard pressure and oxygen content conditions at two different temperatures, 180 °C and respectively 200 °C for short time periods (3 and 5 h). Due to the thermally-aided chemical restructuration of the wood components, a decrease in water uptake and volumetric swelling values with up to 45% for spruce and 35% for oak have been registered, comparing to the reference samples. In relation to water resistance, a 15% increase of the dispersive component of the surface energy has been registered for the thermal-treated spruce panels, which impedes water spreading on the surface. The thermal-treated wood presents superior resistance to accelerated UV exposure and subsequently, with up to 10% higher Brinell hardness values than reference wood. The proposed thermal treatment improves the durability of the finger-jointed wood through a more economically and environmental friendly method than traditional impregnation, with minimal degradative impact on the structural components of wood.

This paper presents the dissimilar laser welding of AISI 321 stainless steel and AISI 1010 carbon steel thin sheets in butt joint geometry using a 1 kW diode laser. Influence of the welding speed on the geometry and microstructure of the joints is discussed. Structural characterisation of the welds is realised through optical, electron microscopy and EDS analysis, observing distinct mixed and unmixed areas in the weld bead because of the high cooling rate. The weld bead presents an austenitic-martensitic-ferrite structure, characterized by austenitic twin grains with ferrite particles precipitated on grain boundaries, and islands comprising a ferrite-martensite structure. Chromium and nickel migration in the weld bead area was observed. Good tensile behaviour of the dissimilar joints was obtained, as all the specimen failure occurs far-off the weld zone.

The improvement of wood-plastic composites properties by additives and compatibilizers is a critical issue to produce value-added materials. High-density polyethylene-wood composites have been obtained through compression molding at 140 °C, using two types of additives, namely methyltrioctylammonium bis (trifluoromethylsulfonyl)imide and trihexyltetradecylphosphonium bis (2,4,4-trimethylpentyl) phosphinate room temperature ionic liquids. The ionic liquids improve the interfacial adhesion between the wood and the polymer phases, contributing to an increased stability of the material to water action and to an improved impact resistance and tensile strength in comparison with the reference. Also, the FTIR spectroscopy tests have proven a higher resistance of the ionic liquid-containing composites to accelerated photooxidation. Preliminary screening tests have also proven the antifungal character of the ionic liquids used in this study against brown rot (Postia placenta). This study opens new insights in the domain of polymeric composite materials, through documenting the possibility of blending new types of chemically distinct materials, difficult to be achieved by traditional functionalization/derivatization routes.

This paper addresses to the characterization of Ni based coatings realized by two different processes e.g. thermal spray coating and laser cladding. For the relevance of the experimental tests, the same base material, AISI 5140 and Metco 15E powder was used. The results highlight the advantages and disadvantages of the both techniques. The cladded layer obtained through laser cladding is pore and crack free, being characterized by a high hardness and a very good adherence to the substrate, while the flame coating presents oxides inclusions, high porosity, lower hardness and minimal dilution with the substrate as resulted from the EDS analyses. In depth characterization of the samples is made using optical and scanning electron microscopy, EDS analysis and microhardness testing.

This paper presents an alternative approach to obtaining crack- and pore-free NiCrBSiFeCuMoC hard coatings on a low alloy steel substrate through coaxial laser cladding, by using Inconel 718 as a buffer layer between the hard coating and the base material. The presence of the buffer layer reduces the overall cracking susceptibility of the hardfacing material by reducing the compressive stresses developed during the cladding process and ensuring a more uniform heat distribution gradient at the surface of the material than the base metal alone, which provides an additional hardness and wear coefficient increase of 7% and improves the corrosion resistance of the obtained materials by 20%, in comparison with the reference sample obtained without an intermediate layer, by using the same operational parameters and minimizes elemental dilution with the substrate. Our method could prove useful in increasing the quality and life cycle of expensive high-performance hard-coated materials, especially those working un...

An improvement in the hardness, wear and corrosion resistance of a thermal-sprayed nickel-aluminium coating has been described in this paper, by using a post-deposition annealing treatment in a vertical concentrated solar radiation furnace at Plataforma Solar de Almeria, Spain. Annealing temperatures between 900 and 970 °C were used. It has been determined that the heat treatment leads to a 56% increase in hardness, 65% increase in scratch resistance and coating adhesion to the substrate, coupled with a 20% improvement in wear resistance, compared to the non-annealed reference. The improvement in mechanical properties has been related to increased heating gradient, formation of intermetallic NixAl compounds in the structure of coatings, as well as to a better compacting of coated assembly. The solar annealing treatment leads also to an improvement in the properties of coatings, with up to 87% in terms of corrosion resistance, and 20% in terms of wear resistance, comparing to the reference.

Advanced oxidation processes catalyzed by functional surfaces represent one of the most versatile methods for removing potentially toxic and persistent organic compounds from aqueous environments. This study is focused on obtaining two types of coatings with complex surface chemistry, involving titanium dioxide, nitrogen-doped titanium dioxide, titanium suboxides, and titanium nitride through a one-step thermal spraying method, starting from titanium feedstock powder. The differences in morphological and structural characteristics of coatings arise from the two different standoff distances between thermal spray nozzle and aluminum substrate (150 mm and 200 mm). The surface energies of the coatings range from 31 to 34 mN/m, which increase with up to 20% upon irradiation with UV light. The optical band gap values of the coatings are 2.01 eV and 1.55 eV respectively, indicating the possibility to harvest electromagnetic radiation from the visible domain in relation to photocatalysis applications. The photocatalytic activity of the surfaces has been tested against methylorange under UV (254 nm and 365 nm) and visible light irradiation. The photodegradation of methyl orange followed a pseudo-first order mechanism, with rate constants in the 0.0039–0.0871 min−1 interval. High photodegradation (91–99%) and dye mineralization (85–97%) efficiencies were registered for both types of coatings.

Palladium supported on carbon nanoparticles has been obtained on a specially designed ceramic catalyst, obtained by thermal spraying on a copper substrate, starting from Pd/C targets. Solar physical vapor deposition in argon, an environment-friendly and energy-efficient alternative to arc or chemical vapor deposition, has been employed as a means of target vaporization at CNRS-PROMES facility in Odeillo, France. The obtained nanoparticles have a spherical-porous morphology with diameters ranging from 50 to 120 nm and specific sorption areas of 50,000 m2/g. The XRD diffractograms indicate the presence of dominatingly crystalline short-range ordered graphene oxide layers, in contrast with the amorphous Pd/C starting precursor. The presence of palladium (0.6% wt.) at the surface of the nanoparticles was proved by the EDX and XRD analyses, making the synthesized material useful in applications such as catalysis or gas sorption.

This paper addresses to the dissimilar laser welding of AISI 304 and AISI 1010 steel thin sheets. Cracks-free dissimilar edge fillet welds have been conducted using a Nd:YAG laser. Geometrical, microstructural, chemical, and mechanical proprieties of the welds were investigated using electron microscopy, EDS and tensile test assisted by digital image correlating. The proper results were achieved at an energy density of 88 J/mm2 using a 0.4 mm laser spot diameter. An austenite-ferrite structure characterizes the weld bead and the precipitation of the chromium carbide at the grain limits was observed in the heat affected zone. Good tensile behavior was obtained; dissimilar joint was fractured on the carbon steel side at 482 MPa and 0.35 stain.

Sections: Fiber laser is a widely used “tool” for micro-machining various materials, in high accuracy condition. Still, there are not set rules and / or principles, so that to be sure of obtaining the required geometric precision for the part. This paper presents some attempts for setting procedures and parameters values domains, so that to further develop technologies for fiber laser micro-drilling of stainless steel sheets, with thickness of 0.5 mm.

The paper presents some aspects regarding tribological characteristics of composite tops of the electrodes for spot welding. The solution aims to improve the resistance to deformation and high intensity electric current conductibility without loses and excessive local heating. The composite material was obtained by mechanical alloying process, from a mixture of tungsten carbide, chromium, CuNiAl alloy and cooper powder which has been heated in furnace at 1100°C. The embedding process aims to avoid the toxic effects of metallic elements such as Be and Zr, which are usually introduced in cupper alloys for improving the mechanical characteristics. The tribological characteristics and microhardness of the melted zone were measured in order to estimate the strengthening effect obtained by the tungsten carbide presence for different mixture recipe.

The use of laser cladding (LC) technology for the improvement of surface properties in various mechanical design applications has given rise to the development of application-oriented composites. The present paper furnishes relevant notes on an experimental approach to the design optimization of experiments regarding WC-Co based layers obtained by laser cladding. The current paper emphasizes the influence of parameter variation on the characteristics of the deposited layer and reports the manner in which the heat input and the laser power density influence the microstructure.

This paper investigates the laser welding of AISI 304 stainless steel thin sheets. For the experimental procedure a 3,3 kW Nd:Yag laser was used. Nine samples were realised during this study and the influence of the process parameters on to the geometry and microstructure of the weld bead is analysed. The best result in case of 0,5 mm stainless steel laser welding are obtained by using a density power in the range of 700-850 kW/cm2 associated with a minimum spot diameter of 0,4 mm. The weld bead compositional content was determined by an X ray dispersive field analyses. A decreasing of Mn and Si content into the weld zone was produced mainly by the burning and vaporization effects during the laser welding. Good tensile behaviour of the joints was obtained at all samples with fracture was produced at 600 MPa.

This study aims to determine the optimal parameters for cold metal transfer MIG welding of aluminum thin sheets. Starting from this perspective, the filler material of Al5Mg full wire type and a synergic regime of welding with a low linear energy were used. The characterization of welded joints was achieved by macro – microscopic analyses, mechanical tests (microhardness and tensile) aiming to lower the thermo - mechanically affected zone. The results highlight the major influence of the welding parameters over the weld bead geometry and tensile behaviour of the joint.

This study focuses on the analysis of the electric field voltage influence on the microhardness of the layers coated by thermal spraying. Based on the fact that the loads that are oppositely signed are attracted, an electric device of electric field generating in alternating current is developed, the electric field being generated between the metalizing gun and the work piece. Any metallic body that crosses the electric field is loaded with electric loads, which are yielded by an electric discharge when meeting the oppositely signed load. Thus, the physical and chemical properties of the layers coated by thermal spraying are improved by enhancing the powders displacement speed and by the appearance of micro weldings at the impact between the powder and the metalizing piece. After the samples analysis, an improvement of the diffusion zone is noticed and also an increasing of the microhardness for the samples at which the following voltages are used U = 30; 50; 70 [. In order to achieve the experimental samples, the CastoDyn DS8000 thermal spraying unit, the standard metallization module SSM 10 and the nickel based powder ProXon 21021 were used.

This investigation concerns the influence of key parameters of laser welding on the geometry and microstructural properties of the weld bead. The study is intended to restrain the interval field of the welding parameters and to investigate the welded joints achieved through this technique. A 3,3 kW Nd:YAG laser together with a Rofin welding head and an ABB 6-axes robot were used for this investigation. The tests highlight the major influence of the laser spot diameter on the geometry of weld bead. The experiments were made on various samples of AISI 304 thin sheets. In depth characterization of the weld area was conducted by means of optic and electronic microscopy and EDS analyses.

The purpose of the present paper is to present a different approach to the finite element modeling of the Vickers hardness test measurement, and to establish a numerical correlation between the Young modulus of a material and its hardness. In order to realize this, calculations were based upon the tensions acquired as a result of the hollow caused in the investigated materials by the indenter the maps of stresses. The present work demonstrates that from the results of the simulation based on the finite element method it is possible to compute a material’s hardness.

In order to obtain high performance calcium carbonate-reinforced HDPE and PP composites, the dispersibility and compatibility of the inorganic phase in the polymer has been achieved through surface treatment of the amorphous calcium carbonate filler with stearic acid. The surface coating of the inorganic phase has been proved by XRD and FTIR spectroscopy, through forming of an intermediate layer of calcium stearate which acts as a surfactant, efficient in providing an optimum compatibility with the dominatingly hydrophobic polymer matrix, as determined from the structural information obtained through samples cross-sections analysing.

To improve the corrosion and wear resistance of copper and its alloys, flame spraying has been employed to obtain a relatively homogenous Cu/Al/Fe-based coating. To minimize the defects that usually occur by using this method, a post-coating annealing step has been employed, by using concentrated solar energy as means of thermal surface treatment. Scanning electron micrographs have indicated a reduction in the cracks/pores density and accelerated corrosion testing have indicated a higher performance of the solar-annealed sample, in comparison with the initial reference material. The coating approach mentioned in this paper could be successfully applied to restore several worn tools and instruments, and could also be of use in the renewable energy field (IR-absorbent coatings) or in advanced oxidation processes, such as photocatalysis.

The aim of this paper is to optimize the operational parameters and quality of one step Metco Inconel 718 atomized powder laser cladded tracks, deposited on AISI 316 stainless steel substrate by means of a 1064 nm high power pulsed laser, together with a Precitec cladding head manipulated by a CLOOS 7 axes robot. The optimization of parameters and cladding quality has been assessed through Taguchi interaction matrix and graphical output. The study demonstrates that very good cladded layers with low dilution and increased mechanical proprieties could be fabricated using low laser energy density by involving a pulsed laser.

This paper addresses to the cold metal transfer MAG welding of low carbon steel thin sheets. The paper highlights the advantages of using CMT process for but joining of S235 carbon sheets by comparing the CMT with the conventional synergic pulse MAG welding. A lower weld bead area and heat affected zone is obtained by the continuous movement of the wire, digitally synchronised with the short-circuit of the arc. CMT welding can produce good welds even in unfavorable conditions, such as using thin plates and high diameter wire.

The paper aims to analyze the effect of the specific parameters values and the surface preparation on the microhardness measurement accuracy. The various force and different time of penetration values has been applied in order to establish the measurement uncertainly in the case of a Bainitic steel sample. Also, the effect of the surface roughness and the scratching test behavior has been analyzed in order to study the superficial material characteristics.

A novel hydrogel was prepared starting with a 10-wt.% lignocellulose solution that was obtained by dissolution of Norway spruce wood (Picea abies) in the ionic liquid 1-butyl-3-methylimidazolium chloride. This ionic liquid was used to avoid traditional degradative and hazardous effects of solvents on the lignocellulose. Five alternate freezing and thawing cycles of the lignocellulose solution were employed as a means of physically crosslinking the hydrogels. The obtained hydrogel network was thermoreversible, with mesopores of 5 to 35 nm diameter, predominantly amorphous, and presenting distinct behaviors when immersed in aqueous solutions with different concentrations of organic electrolytes. The specific surface area of the hydrogel was 75.23 m2×g-1.The hydrogels presented high uptake capacities for pollutant chemical species (Cu2+, Pb2+, and bemacid blue anionic dye) that spanned from 445 mg/L to 547 mg/L at a pH value of 6. This indicated that the hydrogels are promising materials for environmental applications.