Sodium Lignosulfonate Research Articles

Influence and mechanism analysis of different types of water reducing agents on volume shrinkage of cement mortar

This study investigated the impact of five commonly employed water-reducing agents on the fluidity of cement paste at varying dosages firstly. The agents considered in this research are sodium lignosulfonate (LS), naphthalene superplasticizer (PNS), aliphatic superplasticizer (HSB), and two types of polycarboxylate superplasticizers (PCEs), specifically PCE-5C and PCE-6C. Subsequently, the impact of water reducing agents on both the total drying shrinkage and autogenous shrinkage of cement mortar was investigated. This was done by maintaining a consistent water-cement ratio, ensuring good workability, and adjusting the dosage of various water-reducing agents to achieve comparable slump flow in the mortar. Furthermore, the study delved into the mechanisms behind the influence of different types of water-reducing agents. The findings indicate the following: 1) Polycarboxylate superplasticizers (PCEs) exhibit superior dispersion performance with cement, trailed by naphthalene superplasticizer (PNS) and aliphatic superplasticizer (HSB), while sodium lignosulfonate (LS) demonstrates the least effective dispersion performance. The fluidity of cement paste is most responsive to variations in the dosage of PCEs, followed by PNS and HSB, whereas the fluidity of cement paste undergoes minimal changes when the dosage of LS is increased. 2) The effects of various water reducing agents on the volume shrinkage of cement mortar are distinct, and their influence is the outcome of multiple factors working in tandem. These factors include the postponement of the exothermic peak during cement hydration, reduction in solution surface tension, and decrease in the proportion of larger pores and smaller-sized capillary pores within the porosity of cement-based materials, and all these aspects collectively contribute to minimizing the volume shrinkage of cement-based materials. 3) In the realm of concrete engineering, opting for PCEs as water-reducing agents has proven effective in reducing the overall drying shrinkage of cement-based materials. Notably, PCE-5C demonstrates a superior ability in minimizing shrinkage compared to PCE-6C.

Optimasi pH dan Suhu pada Produksi Surfaktan Natrium Lignosulfonat dari Tempurung Biji NyamplungUNG

Tempurung biji nyamplung (Calophyllum inophyllum Linn.) memiliki kadar lignin yang tinggi yaitu sebesar 34,5452% dapat dimanfaatkan sebagai bahan pembuatan surfaktan anionik, sodium lignosulfonat. Pada penelitian ini, dilakukan proses sulfonasi untuk mensubstitusi atom H dengan gugus -SO3H dengan menggunakan sulfonating agent yaitu sodium bisulfit. Penelitian ini bertujuan untuk mengoptimasi suhu dan pH pada produksi surfaktan dari tempurung biji nyamplung dan mengetahui pengaruhnya terhadap kadar surfaktan yang dihasilkan. Penelitian ini dilakukan pada suhu operasi yang bervariasi 600C, 700C, 800C, 900C, 1000C serta pada pH 1,2,3,4,5. Hasil yang didapatkan kemudian dianalisa dengan menggunakan Spektrofotometri UV-VIS yang kemudian dioptimisasi dengan menggunakan metode Respon Permukaan. Kadar terbesar yang dihasilkan dari penelitian ini berada pada suhu 1000C dan pH 5 dengan konsentrasi sebesar 9,16mg/L. Hasil penelitian menunjukkan produksi Sodium lignosulfonat yang optimum sebesar 7,33343mg/L dengan kondisi pH optimum 5 dan kondisi suhu 1000C. Persamaan model adalah

MOFs and surface modification synergistically modulated cellulose membranes for enhanced water permeability and efficient tellurium separation in wastewater

With the widespread use of tellurium-containing products such as cadmium telluride solar cells in daily life, tellurium-containing wastewater inevitably enters the environmental water system. Removal of the ionic contaminant tellurite is essential in wastewater reclamation due to its potential threat to human health and difficulty of elimination. Herein, a rational design of separation membranes with synergistic physical and chemical effects to enhance separation efficiency with almost complete compensation for the loss of water flux was proposed. Membranes for tellurium separation with high efficiency and enhanced water flux were prepared by surface modification on the MOF-based support layer forming a dense separation layer (TSNTCM). The membrane separation efficiency was enhanced by the introduction of NH2-MIL-125 in the support layer, while the water flux was improved by its nano water channels. The abundant hydroxyl and anionic groups in the structure of the polymer monomer sodium lignosulfonate not only endowed the separation layer with chemical interaction (hydroxyl substitution), but also made the membrane surface highly negatively charged and improved the physical interaction. TSNTCM showed excellent tellurium separation efficiency (>95%) over a wide concentration range and achieved the highest rejection (99.16%) at pH = 6. Besides, the rejection of tellurium by TSNTCM was above 90% in the presence of common coexisting ions, but decreased in the presence of selenite, which may be due to the similar structure and properties of selenite and tellurite. Moreover, TSNTCM demonstrated satisfactory reusability and anti-fouling properties. Overall, MOFs and surface modification enhanced the comprehensive performance of TSNTCM, providing great potential for its application in wastewater reclamation.

Preparation and properties of water‐borne polyurethane‐sodium lignosulfonate/nano‐calcium carbonate composites

AbstractTo improve the application range of waterborne polyurethane (WPU), in this study, nano calcium carbonate/sodium lignosulfonate (CaCO3/SL) composites were prepared using sodium lignosulfonate (SL) wet‐modified calcium carbonate nanoparticles. Then, a series of waterborne polyurethane (WPU) nanocomposites (WPU‐CaCO3/SL) were prepared by solution mixing. Zeta, FT‐IR, XRD, SEM, and TGA were used to characterize the structure and morphology of CaCO3/SL and WPU‐CaCO3/SL. By conducting an analysis on the impact of various dosages of CaCO3/SL composite on the performance of WPU, the findings revealed that the tensile strength of WPU‐CaCO3/SL nanocomposites, when composed with a 3 wt% CaCO3/SL dosage, exhibited a significant increase of 116% from 6.93 to 14.95 mPa. The water contact angle demonstrated a significant increase from 78.3° to 90.1°. Additionally, the maximum decomposition temperature showed a noticeable rise of approximately 7°C. The WPU exhibit enhanced heat resistance, water resistance and mechanical properties, as well as exceptional ultraviolet (UV) absorption capabilities. This study provides a reference for modifying polymers with inorganic fillers and improving the optical properties of polymeric materials.Highlights Successful modification of nano calcium carbonate using biopolymer SL. Modified CaCO3/SL can be uniformly dispersed in water. Improved thermal stability of WPU composites. WPU composites exhibit excellent mechanical properties and water resistance. Well‐dispersed CaCO3/SL improves ultraviolet radiation resistance of WPU composites.

The Mechanical Properties and Water-Reducing and Retarding Mechanism of a Xylonic Cement Admixture.

This study explores the mechanical properties, as well as the water-reducing and setting delay mechanism, of a novel xylonic acid-based water reducer applied to cementitious materials. Four xylonic acid water reducers were synthesized in this study: XACa (PX) from pure xylose, XACa (HS) from hemicellulose hydrolysate, XANa (PX) from pure xylose, and XANa (HS) from hemicellulose hydrolysate. These were generated through the whole-cell catalysis of Gluconobacter oxydans bacteria, using pure xylose and hemicellulose hydrolysate as substrates. The findings indicate that the xylonic acid-based water reducer can attain a water-reducing capability between 14% and 16% when the dosage (expressed as a mass fraction of cement) is roughly 0.2%. In initial and final setting tests, XACa (PX) demonstrated a pronounced retarding influence at admixture levels below 0.15%, reaching its apex at 0.10%. This delayed the initial setting time by 76% and the final setting time by 136% relative to the control group. However, a slight pro-setting effect was noted beyond a 0.2% dosage. In the compressive and flexural tests of concrete, under the same slump, the XA group improved its mechanical properties by 5% to 10% compared to the SodiuM lignosulfonate (SL) group. In the air content and chloride ion migration resistance tests, the XA group reduced the air content by 38% compared to the SL group, but also increased the data of rapid chloride migration (DRCM) by 16%. Characterization studies revealed that the carboxyl and hydroxyl groups in xylonic acid undergo chemisorption with the Si-O bonds on the surface of cement particles. These groups interact with the Si-O bonds on cement particles, contributing to water-reducing effects and delaying the setting process by impeding Ca2+ ion aggregation in the calcium-silicate-hydrate gel. Its significant water-reducing effect, adjustable setting time, and excellent mechanical and durability properties suggest its viability as an alternative to lignosulfonate series water-reducing agents.

Carbon steel anticorrosion performance and mechanism of sodium lignosulfonate

Carbon steel anticorrosion performance and mechanism of sodium lignosulfonate

Biosynthesis of copper oxide nanoparticles (CuO NPs) using sodium lignosulfonate and evaluation of its cutaneous wound healing properties

Repairing cutaneous wounds imposes a lot of cost on the country every year. Also, cutaneous wounds healing is delayed for various reasons such as the accumulation of free radicals, hospital infections, lack of sufficient moisture, traditional dressings, etc. Therefore, treatment methods need to be reviewed. In recent years, a wide range of copper ointments or silver-releasing compounds have been prepared and used. These ointments have overcome some of the problems associated with copper preparation. In the current work, an environment-friendly a green procedure was described for fabrication of CuO NPs by using sodium lignosulfonate as a capping/stabilizing reagent under alkaline medium. The characterization of prepared CuO NPs@NaLS were analysed using SEM, EdaX, ICP-OES, elemental mapping and TEM data. The FE-SEM and TEM results show that the CuO NPs@NaLS formed as spherical NPs with size of 20–30 nm. According to the elementaling map analysis, the Cu and C were existence with good dispersion that detected by EDX in the composite. In this study, ointments with a concentration of 0.1% were prepared from nanoparticles based on basal ointment (as the main substance that keeps the medicine on the wound) and used as a topical application. In this way, on the second day, angiogenesis (angiogenesis) and the severity of edema and edema, on the fifth day, fibroblasts, and on the tenth, fibrocytes and collagen fibers were examined. According to the present study results, the skin wound area in the rats treated with topical use of NPs was significantly reduced, and in terms of histopathology, it showed more improvement compared to other groups. Overall, the results of this study show that recent nanoparticles can be used as a fast and effective treatment for skin wounds healing.

Physiological Responses of Cucumber Plants to Sodium Lignosulfonate Application to Sandy Loam Soil

The use of lignosulfonates (LS) to improve soil fertility is currently under study and discussion. The effect of sodium LS application in the sandy loam soil on the accumulation of biomass, photosynthesis, respiration and their coupling in cucumber plants was studied. The LS rate of 10–25 g/kg did not have a significant effect on the studied parameters of the physiological state of plants. However, at a high LS content (50–100 g/kg), the plant growth rate and activity of the photosynthetic apparatus decreased, and the respiration rate increased, which caused the increase in the ratio of respiration to photosynthesis. The negative effect of high concentrations of LS on the physiological state of cucumber plants and their cold resistance is presumably associated with sodium salinization of the soil.

Adsorption and Dispersion Effect of Sodium Lignosulfonate on Fine SiC Particles in Aqueous Media.

This study presented a novel modification method for fine SiC powder by using sodium lignosulfonate as a dispersant. The adsorption behavior of sodium lignosulfonate on the SiC/water interface and its effect on the performance of a fine SiC slurry were systematically investigated. The adsorption results showed that sodium lignosulfonate formed monolayer adsorption on the surface of fine SiC and that the saturated adsorption capacity was 1.3263 mg/g. The adsorption reached equilibrium within 3 h and was mainly controlled by active sites on the SiC surface. The dispersion, stability, and zeta potential of modified SiC powder were improved after sodium lignosulfonate adsorption. The zeta potential of modified SiC reached a minimum value of -44.8 mV at pH 12. Modified SiC suspensions had great stability in a wider pH range of 6-12. Modified SiC slurry with 54 vol % solid loading had a low viscosity of 173 mPa·s at pH 10. Subsequently, coarse SiC powder was added for slip casting. A mixed slurry with high solid loading (69 vol %) and low viscosity (583 mPa·s) was prepared using modified SiC and coarse SiC powders at a mass ratio of 2:3. Finally, recrystallized SiC green body with high density (2.6492 g/cm3) was obtained.

Sodium lignosulfonate-modulated small-size BiOCl–C nanosheets with excellent visible light degradation of organic pollutant

In this paper, BiOCl–C composites were prepared using sodium lignosulfonate (SLS) as the carbon source. SLS also acted as a surfactant, and the BiOCl–C nanosheets gradually became smaller with the increase of SLS dosages. When SLS was added at 0.4 g, the formed BiOCl–C nanosheets had the best effect in terms of size and photocatalytic activity. Compared with pure BiOCl, the small size BiOCl–C nanosheets showed better degradation of rhodamine B (RhB) and could eliminate 90.2 % RhB under light conditions. This might be due to the incorporation of carbon material which increased the specific surface area and decreased the electron-hole recombination rate. Meanwhile, BiOCl–C obtained higher electron mobility rate under the small size effect, which improved the photocatalytic degradation efficiency. Therefore, the prepared BiOCl–C is a promising photocatalyst for degrading organic pollutants. This work provides a new idea for the design of efficient environmental catalytic photocatalysts.

STABILIZATION OF WATER-COAL COMPO­SITE FUELS USING CARBON MICRO-NANO­MATERIALS AND AMINO ALCOHOLS

The study investigated the potential of stabilizing composite water-coal fuel (CWCF) by adding carbon micro-nanomaterials obtained through the plasma-chemical conversion of organics-containing wastewater and amino alcohols. The study focused on systems based on anthracite with a solid phase concentration of 62%. Two amino alcohols, 2-amino-­2-methyl-1-propanol (AMP) and 2-amino-­2-ethyl-1,3-propanediol (AEPD) were used at concentrations of 0.25%, 0.5%, 1%, and 2.5% by weight of CWCF.
 The low stability and heterogeneity of coal particle distribution in organic liquids cause an increase in the viscosity of dispersed systems in combined systems. To regulate the rheological properties and stabilize the CWCF, chemicals such as dispersants, plasticizers, and stabili­zers are added. The CWCF 's properties can be improved by using additives such as sodium, calcium, and magnesium lignosulfonates, and naphthalene sulfonic acids. However, these reagents may not provide the desired properties of coal slurries in organomineral environments. Therefore, substitutes for these pro­ducts need to be found.
 Amino alcohols are commonly used as dispersants and stabilizers, especially in the production of water-based paints. They are low in cost, low in toxicity, and serve as anti-corrosive agents and pH stabilizers without causing excessive foaming. To strengthen the spatial structure, reactive particles such as carbon micro- and nanomaterials (CNM) can be introduced into the CWCF. Unlike polyelectrolytes and surfactants, CNM particles can have a varying number of active centers depending on the method of formation. By varying the properties of CNMs, it is possible to increase the number of contact centers and form a spatial grid without increasing the concentration of surfactants and polyelectrolytes. This is because contact interactions are activated during grinding, forming a new surface with energy-saturated active centers. As a result, the concentration of the system can be increased, and the calorific value of the fuel can be increased as well. However, the presence of an organic component can render mechanochemical activation ineffective by shielding active sites with large organic molecules. Therefore, identifying the most effective stabilizer reagents and deve­loping technology for their introduction into the dispersed system is a crucial and intricate problem in obtaining CWCF
 The study revealed that the ξ potential of anthracite particles is 40–45 mV in the pre­sence of amino alcohols. Sedimentation stabi­lity in the presence of highly dispersed carbon additives increases from 5–6 to 10–14 days, i.e., almost twice. The introduction of highly dispersed carbon leads to an increase in the effective viscosity of the systems and can be recommended for controlling the fluidity of the CWCF. The technical and operational requirements are best met by the CWCF containing 0.25% AMR and 1% highly dispersed carbon.

Combustion behavior, mechanical performance and application for vinyl acetate–ethylene copolymer emulsion containing melamine amino trimethyl phosphate and sodium lignosulfonate

AbstractAn intumescent‐flame‐retardant vinyl acetate–ethylene copolymer (IFR/VAE) compound has been prepared by blending with a complex of melamine amino trimethyl phosphate (M‐AT) and sodium lignosulfonate (SL). Then, this obtained IFR/VAE polymer was applied as adhesives for producing the flame‐retardant plywood. The IFR VAE sample (VAE/M‐AT3/SL1) with a mass ratio 3:1 (M‐AT to SL) showed an enhanced amount of char residue, limiting oxygen index (LOI) value and tensile strength value to 20.6 wt%, 32 vol% and 19.3 MPa, which have been increased by 796%, 600%, and 56% compared to that of neat VAE. The cone calorimeter result showed that the peak of heat release rate (pHRR) of VAE/M‐AT3/SL1 sample was reduced by 48% compared to the control one. Additionally, the second peak of HRR of sample IFRPW/15 L/15 (containing 15 wt% M‐AT3/SL1 in the plywood adhesive layer) presented a reduction of 29% compared to that of the sample PW/15 L (neat plywood). It is assigned to the formation of phospho‐carbonaceous structure during combustion, thus the flame‐retardancy of plywood has been greatly enhanced. Thus, this work provides an economical and applicable fire‐retardant VAE adhesive formula for producing plywood materials with good performances.

Activation-self-activation craft for one-step synthesis of GO-inbuilt mesopore-dominated N-doped hierarchical porous carbon in capacitive deionization capture of Ni(II)

Capacitive deionization (CDI) is considered a polar-promising technology to remove heavy-metal ions from wastewater. Herein, a green activation-self-activation strategy was exploited to build graphene (GO)-inbuilt mesopore-dominated N-doped hierarchical porous carbons (ENHPCs) using sodium lignosulfonate (SLS) as carbon sources/self-activators. Different from SLS self-activation and K2C2O4-SLS activation-self-activation, ENHPCLKG gained via GO-mediated K2C2O4-SLS activation-self-activation showed suitable mesopore-dominated micro-mesoporous structures with high surface area of 1795.5 m2/g, large mesoporous volume of 0.87 m3/g, 3.65 % N-doping and excellent conductivity. Its unique hierarchical porous structure and abundant active sites facilitated the ion rapid insertion and extraction. When utilized to capture low-concentration nickel (Ni2+) ions, ENHPCLKG delivered splendid salt removal capacity of 17.86 mg/g, rapid average salt removal rate of 0.99 mg/g/min and standout cycle stability. Meanwhile, ENHPCLKG was further extended to remove NaCl, MgCl2, CaCl2 and Ni-containing wastewater, showing superior CDI property. Moreover, the recycled ENHPCLKG (10th) taken to eliminate indomethacin (IDM) depicted a splendid adsorption capacity. This work proved the significant applicant potential of the novel and green ENHPCLKG for disposing of Ni2+ ions via CDI technology.

Effect and enhancement mechanism of sodium lignosulfonate on the chitosan-based composite film

Chitosan is a desirable alternative for petroleum-derived packaging materials, but the unsatisfactory performance of most chitosan composites drastically impedes their practical application. In this work, a facile physical blending strategy was selected to prepare chitosan-based composite films with good properties utilizing sodium lignosulfonate as a reinforcing agent. The effects of sodium lignosulfonate addition on the barrier performance, antioxidant activity, UV-blocking, and mechanical properties of the composite films were evaluated. The enhancement mechanism of sodium lignosulfonate on the structural and functional properties of the membranes was also investigated. The results show that chitosan mixed with sodium lignosulfonate exhibited a higher tensile strength (∼75Mpa), improved barrier property (OTR and WVTR are 4.8 g·m−2·d−1 and 415 g·m−2·d−1, respectively), increased free radical scavenging activity (29.9 %), and enhanced UV-blocking ability (95 %) compared to pure chitosan film. Strong electrostatic interaction and hydrogen bonding between monodispersed sodium lignosulfonate and chitosan have an essential effect on the performance of composite films. The application of sodium lignosulfonate as a reinforcing material is both environmentally friendly and economically viable, showing promising potential for use in food packaging applications.

Suppressing Dendrite Growth with Eco-Friendly Sodium Lignosulfonate Additive in Quasi-Solid-State Li Metal Battery.

The application of lithium metal batteries is limited by the drawbacks of safety problems and Li dendrite formation. Quasi-solid-state electrolytes (QSSEs) are the most promising alternatives to commercial liquid electrolytes due to their high safety and great compatibility with electrodes. However, Li dendrite formation and the slow Li+ diffusion in QSSEs severely hinder uniform Li deposition, thus leading to Li dendrite growth and short circuits. Herein, an eco-friendly and low-cost sodium lignosulfonate (LSS)-assisted PVDF-based QSSE is proposed to induce uniform Li deposition and inhibit Li dendrite growth. Li symmetric cells with 5%-LSS QSSE possess a high Li+ transfer number of 0.79, and they exhibit a long cycle life of 1000 h at a current density/areal capacity of 1 mA cm-2/5 mAh cm-2. Moreover, due to the fast electrochemical dynamics endowed by the improved compatibility of the electrodes and fast Li+ diffusion, the LFP/5%-LSS/Li full cells still maintain a high capacity of 110 mAh g-1 after 250 cycles at 6C. This work provides a novel and promising choice that uses eco-friendly LSS as an additive to PVDF-based QSSE in Li metal batteries.

Biomass derivatives self-assembled into multiple heteroatoms doped carbon sphere for aqueous Zn-ion hybrid capacitors

Zinc ion hybrid capacitors (ZHCs) as a new type of energy storage device, possess high power density, low cost, and safety. However, the unsatisfactory energy density of ZHCs caused by low output voltage and small specific capacitance restricts its practical application. Herein, a novel multiple heteroatoms doping carbon sphere is achieved from the mixture precursors of glucosamine hydrochloride and sodium lignosulfonate via chemical activation strategy. High specific surface area, rich O/N/S-containing functional groups, and good electric conductivity endow the resultant carbon sphere with a superior specific capacity of 233 mAh g−1 at 1 A g−1 and outstanding capacity retention of 83 mAh g−1 at 50 A g−1. Remarkably, as-assembled ZHC exhibits a conspicuous energy density of 209.7 Wh kg−1 at 900 W kg−1, and its energy density still maintains 74.7 Wh kg−1 at 45,000 W kg−1. Furthermore, after 10,000 cycles, the resultant carbon sphere achieves 100% capacitance retention. This work offers a feasible strategy for carbon cathode materials with enhancing energy density and rate capability, and concurrently reasonable cycling stability.

Enhancing Pollutant Mineralization through Organic-Inorganic Defect-Transit Dual S-scheme with a Robust Internal Electric Field.

Achieving superior photomineralization of pollutants relies on a rational design of a dual S-scheme with a robust internal electric field (IEF). In this study, to tackle the low mineralization rate in type-II In2 O3 /In2 S3 (IO/IS) systems, an organic-inorganic dual S-scheme In2 O3 /PDI/In2 S3 (IO/PDI/IS) nanostructured photocatalyst is synthesized via a method combining solvent-induced self-assembly and electrostatic forces. Due to the unique energy band position and strong IEF, the photoinduced defect-transit dual S-scheme IO/PDI/IS facilitates the degradation of lignin and antibiotics. Notably, a promising mineralization rate of 80.9% for sodium lignosulfonate (SL) is achieved. The charge transport pathway of IO/PDI/IS are further validated through the analysis of in situ X-ray photoelectron spectroscopy (in situ XPS), density functional theory calculations, and radical trapping experiments. In-depth, two possible pathways for the photocatalytic degradation of lignin are proposed based on the intermediates monitored by liquid chromatography-mass spectrometry (LC-MS). This study presents a new strategy for the design of organic-inorganic dual S-scheme photocatalysts with a robust IEF for pollutant degradation.

Efficient depolymerization of sodium lignosulfonate assisted by sulfur migration

Lignosulfonate (LS), as the most abundant technical lignin, is hard to depolymerize due to highly condensed structure. To overcome the limitation, in this work, NiMoO4/Al2O3 catalyst with regulated acidity/hydrogenation activity was developed for highly efficient LS depolymerization. Results show that the performance of NiMoO4/Al2O3 was improved by sulfur migration. Meanwhile NiMo alloy contributed to the good stability during LS depolymerization. The NiMoO4/Al2O3 was favor for the intermediate compounds production by the cleavage of CO and CC bonds, which intermediate compounds were eventually hydrogenated to monomers by highly active MoS2. Also, NiMoO4/Al2O3 and sulfonic groups play a synergistic role in the sulfur migration (only 39.1% bio-oil yield obtained by MoS2/Al2O3). After reacting at 300 °C for 4 h, 81.7% of bio-oil yield with 95% desulfurization rate were obtained. Thus, it was demonstrated that an inexpensive catalyst was developed which can efficiently catalyze the depolymerization of lignosulfonate.

Comparative study of lignin and sodium lignosulfonate extracted from irradiated and non-irradiated sawdust wastes

Recent technologies in the production of chemicals and bio-material products are focusing on lignocellulosic biomass resources since it is the world's most abundant economical material, recyclable, sustainable, low cost, as well as highly renewable natural resources. This biomass refers to agricultural wastes such as woody plants (soft and hardwood). Lignin is extracted from these agro-wastes using chemical methods and ionizing radiation. The outcome of employing gamma radiation as a pretreatment step prior chemical treatment on the duration for alkaline, acid, and production of sodium lignosulfonate (NaLS) was examined. The structure of the produced NaLS was verified utilizing Nuclear magnetic resonance (1H-NMR, 13C-NMR) and Liquid chromatography–mass spectrometry (LC–MS). A comparison between the physicochemical properties of sodium lignosulfonate extracted from both non-irradiated and irradiated sawdust waste was studied using FTIR, XRD, EDX and TGA. The degree of sulfonation of the produced NaLS was determined utilizing the potentiometric titration method. The findings demonstrated that gamma exposure pretreatment step reduces the time of alkaline, acid, and sulfonation processes as well as a higher yield percentage and degree of sulfonation.

Smart controlled-release avermectin nanopesticides based on metal–organic frameworks with large pores for enhanced insecticidal efficacy

Nanopestcides based on metal–organic frameworks (MOFs) have attracted great attention. Highly stable mesoporous metal–organic framework PCN-777 with large pores can accommodate the biologically active insecticide avermectin (AVM) of relatively large molecular dimensions. In this work, PCN-777 nanoparticles were synthesized for the creation of double-gated nanopesticides with sodium lignosulfonate (SL) and chitosan. The double gatekeepers could realize excellent sealing performance to prevent premature leakage of AVM. The double-gated PCN-777 based nanopesticides could achieve the controlled release of AVM in response to pH, laccase, phosphate, and phytic acid (PA), which are related to the physiological environments of pests and crops. The PA-triggered controlled release of loaded cargos in MOF-based delivery systems was reported for the first time. This is the first example of PCN-777 drug/pesticide delivery system and also the first case of controlled-release MOF-based AVM nanopesticides, and the mechanisms of the stimuli-responsive controlled pesticide release were clearly elucidated. The nanopesticides prevented the ultraviolet photolysis of AVM owing to the PCN-777 organic ligands and SL coating. The nanopesticides had high insecticidal efficacy and field control efficacy against the pests Spodoptera litura Fabricius on cabbage, in comparison with traditional pesticide formulations, and the nanopesticides had no influence on plant growth and showed high biosafety toward non-target organisms and human cells. The smart controlled-release nanopesticides show high potential and application prospect in ecological agriculture.