Lignin is a major by-product of the wood and paper industries. Valorization of this complex organic polymer, through the creation of novel high-value side products, is a key aspiration of these industries. Due to its unique chemical composition, lignin can be efficiently used to produce many fine chemicals. In this review, we discuss various techniques and strategies used to synthesize lignin-derived functional materials. The transformation of lignin during pyrolysis and hydrothermal carbonization is also reported. Furthermore, current applications and surface properties of lignin-based carbonaceous materials in the fields of catalysis, bio-adsorption removal of pollutants, and supercapacitors are summarized.

Triphenylene-containing trifluorovinyl ether monomers prepared from 2,3-disubstituted-bis-1,4-(p-bromophenyl)triphenylene core building blocks undergo thermal step-growth polymerization (Ph 2 O, 180 °C), affording perfluorocyclobutyl polymers with unprecedented glass-transition temperatures (up to 295 °C), excellent high thermal-oxidative stabilities, and solution processability. The modular synthetic route provides access to a series of triphenylene monomers from a common cyclopentadienone derivative and variably substituted alkynes, which polymerize thermally to solution-processable, tough, transparent films with bright blue solid-state photoluminescence (λ em = ∼400−470 nm). Conversion was monitored by 19 F NMR end-group analysis and gel permeation chromatography to reasonably high molecular weights (M n = 45−93 kDa). Remarkably, photoemission persists at 250 °C in air for 24 h with negligible changes in absorbance and emission wavelengths after cooling to room temperature.

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Aim: Hollow-fiber-based supported liquid membrane was modified utilizing nanostructures such as graphite, graphene oxide or nitrogen-doped graphene oxide, for electro-membrane extraction (EME) of imatinib and sunitinib from biological fluids. By applying these conductive nanostructures, a low-voltage EME device (6.0 V) was fabricated. Materials & methods: A response surface methodology through central composite design was used to evaluate and optimize effects of various essential factors that influence on normalized recovery. Results: Optimal extraction conditions were set as, 1-octanol with 0.01 % (w/v) graphene oxide functioning as the supported liquid membrane, an extraction time of 17.0 min, pH of the acceptor and the donor phase of 2.8 and 7.9, respectively. Conclusion: The method was successfully applied to quantify imatinib and sunitinib in biological fluids.

A new composite of cobalt ferrite and Tragacanth gum (TG) was developed and applied to remove methyl orange (MO) and methyl red (MR) from wastewater samples simultaneously. The results showed that the presence of TG improved the capability of cobalt ferrite in removing the pollutants in considerably. The adsorption properties and surface morphology of the sorbent were compared with those of bare cobalt ferrite, TG, and TG grafted copolymer. The properties of the adsorbents were studied using Fourier transform infrared, scanning electron microscope, transmission electron microscope, X-ray diffraction, and vibrating sample magnetometer, and the effects of different factors such as the amount of the adsorbent, sample pH, contact time, and initial concentration were also evaluated and optimized through response surface methodology using central composite design. The optimal conditions for the adsorption of both dyes (100 mg L −1 as the concentration) were pH of 4.0, adsorbent dose of 0.5 mg mL −1 , and contact time of 110 min. Under these conditions, the MO and MR adsorption processes were found to follow pseudo-second-order kinetic model. The equilibrium adsorption data followed the Langmuir isotherm and the highest adsorption capacity was determined to be 336 and 387 mg g −1 for MO and MR, respectively.

Electromembrane extraction was used with high‐performance liquid chromatography for preconcentration and determination of ampicillin residues in cow milk. Ampicillin is transferred from an aqueous solution through a thin layer containing octan‐1‐ol, silver nanoparticles, and reduced graphene oxide which serves as a supported liquid membrane. Inside the fiber impregnated with supported liquid membrane mixture was filled 10 µL of an acceptor phase. Experimental parameters were optimized for extraction efficiency of ampicillin. Under the optimized conditions, the proposed method provided acceptable linear range (2–100 µg/L), satisfactory repeatability (RSD% < 7.1), low limit of detection (0.6 µg/L), and a high enrichment factor (295) corresponding to extraction recovery of 37%. Consequently, the proposed method was successfully applied for the determination of ampicillin residues in different cow milks.

A hybrid nanocomposite cobalt ferrite and Tragacanth gum, denoted as Co x Fe 3-x O 4 @silica@TG was developed and applied in concurrent removal of chromate and nitrate ions from wastewater. The results showed that the presence of Tragacanth gum considerably improved the capability of cobalt ferrite for removing the pollutants. The adsorption properties and surface morphology of the sorbent were compared with those of bare cobalt ferrite, Tragacanth gum, and Tragacanth gum crosslinked copolymer. The properties of the proposed nanocomposite were studied using FT-IR, transmission electron microscopy (TEM), and vibrating-sample magnetometer (VSM) techniques. The effect of different factors including the amount of the adsorbent, sample pH, contact time and initial concentration was also evaluated and optimized through response surface methodology using central composite design. The optimal conditions for the adsorption of both chromate and nitrate ions (30 mg L À 1 as the concentration of both of them) were pH = 3, an adsorbent dose of 1 mg mL À 1 and 22.4 min contact time. The adsorption process was found to follow the pseudosecond order and intra-particle diffusion kinetic models. The equilibrium adsorption data followed the Langmuir isotherm and the highest adsorption capacity was determined to be 44.1 and 30.7 mg g À 1 for chromate and nitrate, respectively.

Nitrates and phosphates, found in fertilizers, are the most common eutrophication-causing agents. Douglas fir biochar (BC), a syngas byproduct, was treated with different Al/Mg ratios of sulfate (5% w/w metal loading) followed by an NaOH treatment. The greatest phosphate uptake at 25 °C and pH 7 was attributed to the composite with a Mg/Al 2:1 ratio prepared at pH 13 (AMBC). Batch AMBC phosphate uptake was optimized for initial pH, equilibrium time, temperature, and initial phosphate concentration. Phosphate removal following pseudo-2nd-order kinetics and increases gradually before reaching a max at pH 11, with 95% phosphate uptake in 15 mins. The Sips isotherm model provided the best sorption data fit resulting in a 42.1 mg/g capacity at 25 °C and pH 11. Endothermic and spontaneous adsorption were determined using van ’t Hoff’s plots. BET, XRD, XPS, SEM, TEM, and EDS were used to characterize the biochar before and after phosphate sorption. Used AMBC has the potential to be exploited as a phosphate fertilizer as a key part of an environmentally friendly agricultural management plan.