Silica conjugated with kraft lignin and its use as a novel ‘green’ sorbent for hazardous metal ions removal

Bula

et al. 2016

J Therm Anal Calorim

Self Cite

In this paper, amorphous silica Syloid 244 and kraft lignin were mechanically coupled. Four hybrid materials containing silica and lignin in ratios 1:1, 2:1, 5:1 and 20:1 were prepared. As reference samples for hybrid fillers pristine silica and lignin were used. Particle size determination and microscopic observations were applied to determine dispersive and morphological properties of hybrid fillers. Fourier transform infrared spectroscopy confirmed the effective preparation of silica/lignin hybrid materials. The parameters of porous structure of examined hybrid filler were determined using the multipoint Brunauer-Emmett-Teller method and Barrett-Joyner-Halenda algorithm. Composite samples of polylactide (PLA) containing 2.5 % (w/w) of hybrid filler were extruded. Optical microscopy, wide-angle X-ray scattering and differential scanning calorimetry were applied to specify the supermolecular structure of functional PLA/hybrid composites and analyze the crystallization parameters as well as the phase transformation in PLA matrix. Silica/lignin hybrid material was found to be a filler capable of an effective crystal nucleation. The nucleating ability of silica/lignin hybrid filler in PLA matrix is related to porous properties of filler and its composition.

Section: Introductionmentioning

confidence: 99%

Supermolecular structure and nucleation ability of polylactide-based composites with silica/lignin hybrid fillers

Grząbka-Zasadzińska

Bula

et al. 2016

J Therm Anal Calorim

Self Cite

“…Silica with its good mechanical and thermal resistance can form interesting combination with cheap and environmentally friendly lignin. New hybrid materials may be used as functional biosorbents [41,42] and also as polymer fillers [43]. The high interest for these materials is the effective surface of the nanosized filler making it possible to tailor and handle the properties of the material with very small proportions of the filler.…”

Section: Introductionmentioning

confidence: 99%

Nucleation ability of advanced functional silica/lignin hybrid fillers in polypropylene composites

Borysiak

Bula

et al. 2016

J Therm Anal Calorim

Self Cite

Novel advanced functional silica/lignin hybrid fillers were synthesized for the purpose of their application in composites with polypropylene. The use of lignin for the production of hybrid fillers is justified due to the advantages such as reduction in cost of products, improvement in biodegradability as well as antioxidant and antimicrobial properties. The study encompasses an analysis of the dispersive and morphological properties of the hybrid fillers, and investigations of phase transitions and the supermolecular structure of the composites by means of differential scanning calorimetry, polarized light microscopy, and X-ray diffractometry. The nucleation activity of the hybrid fillers was found to be strongly correlated with the chemical composition of the fillers, and their dispersive properties and porous structure characteristics. Furthermore, the particle size and area surface of the hybrid fillers play an important role in the development of polymorphic varieties of the polypropylene matrix. The study also discusses the mechanism of the formation of the b-PP variety and the transcrystalline structure in the context of the nucleation ability of the hybrid fillers. The investigations are very significant because they address the impact of the actual physicochemical parameters of the hybrid fillers on the nucleation ability and structure of composite materials.

“…This sorbent was prepared from the widely available waste biopolymer lignin, as described in our previous paper 23 . Combining lignin with silica produced a relatively cheap material with a high BET surface area of 223 m 2 /g 23 and very favorable physicochemical properties.…”

Section: Adsorption Effi Ciencymentioning

confidence: 99%

“…This material has been studied in detail, in terms of physicochemical and dispersive-morphological properties, in our previous papers 21, 22 . Moreover, recently published results prove that this material offers good sorption capabilities with respect to nickel(II) and cadmium(II) ions 23 . However, more advanced investigations suggest that the silica/lignin material is even more effective at adsorbing lead(II) ions.…”

Section: Introductionmentioning

confidence: 99%

Removal of lead(II) ions by an adsorption process with the use of an advanced SiO₂/lignin biosorbent

Polish Journal of Chemical Technology

Bartczak

Szatkowski

et al. 2017

Self Cite

We demonstrate here that lignin can be successfully combined with silica to create a multifunctional material with considerable sorption capabilities. Experiments were carried out in which a silica/lignin hybrid was used for the removal of lead(II) ions from water solutions. Adsorption kinetics were also determined and preliminary regeneration tests were performed. The effectiveness of the adsorption process depends on the following parameters: contact time of adsorbent and adsorbate (equilibrium times: 5 min for concentration 25 mg/L, 10 min for 50 and 75 mg/L, 60 min for 100 mg/L), pH (optimal pH = 5) and adsorbent mass. The kinetics of the adsorption of lead(II) ions on the SiO 2 /lignin biosorbent are best described by a pseudo-second-order model. Adsorption isotherms of lead(II) ions were also determined. The experimental data were found to be in agreement with the Langmuir model, and the maximal sorption capacity of the adsorbent with respect to lead(II) was 89.02 mg/g.