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Optimization of Sodium Lignosulfonate Treatment on Nylon Fabric Using Box–Behnken Response Surface Design for UV Protection

Singh Gangwar Arun Kumar, Shakyawar D B, Singh Mukesh Kumar, Vishnoi Prashant, Jose Seiko

Autex Research Journal

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2022

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Vol. 22, no. 2

248--257

EN

The effect of sodium lignosulfonate (LS) treatment on nylon fabric for enhancing its ultraviolet protection ability has been studied. Various concentrations of LS were applied on nylon fabric using the exhaust method and the treatment was optimized using Box–Behnken response surface design. The ultraviolet protection factor (UPF) is achieved, as high as 62.13 with one such LS-treated nylon fabric. The LS-treated nylon fabrics were characterized using FTIR, FESEM, Energy dispersive X-ray (EDX), and Thermo-gravimetric analysis (TGA) instruments. The UPF and color-strength (K/S) values are signifi cantly increased with an increase in the concentration of LS without any loss of tensile properties and thermal stability. The LS treatment has excellent wash fastness.

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Combining laccase with Cu(salen) catalysts for oxidation of kraft lignin

Zhou X. F., Tang K.

Drewno : prace naukowe, doniesienia, komunikaty

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2016

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vol. 59, nr 198

35--47

EN

The transformation of kraft lignin using laccase with Cu(salen) catalysts was studied. The effect of the laccase/MCM – to – laccase/MCM + Cu(salen)/NaY ratio on the yields of monomeric aromatic chemicals (MACs) and the molecular weight (Mw) of kraft lignin was studied. The MACs yield decreased as the ratio increased, and the vanillin yield reached its highest value when the ratio of laccase was 50 wt % at a reaction temperature of 80 °C. The formation of MACs was enhanced by using a combination of laccase with Cu(salen) catalysts, while the formation of vanillin was dominant in the process. The formation of 4-hydroxy-3,5-dimethoxy benzaldehyde, 2-methoxy phenol, 4-hydroxy-3,5- -dimethoxyphenyl ethanone, 4-hydroxy-3-methoxyphenyl ethanone, 4-hydroxy- -3,5-dimethoxy benzoic acid, 4-hydroxy benzaldehyde, and 2-methoxy-4- -vinylphenol was also found in this work. The effect of the reaction parameters on the MACs yield and the Mw of the kraft lignin was described, and the main reactions occurring in the kraft lignin were discussed.

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The degradation of kraft lignin during hydrothermal treatment for phenolics

Tang K., Zhou X. F.

Polish Journal of Chemical Technology

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2015

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Vol. 17, nr 3

24--28

EN

Kraft lignin was hydrothermally depolymerized at low temperature/short time in water for producing value-added phenolics. The effects of residence time (15, 60 min) and reaction temperature (130, 180, 230ºC) on yields of oils and phenolic compounds were studied in detail. Total oil yield was found to range between 7% and 10%. The compositions of oils were analyzed by GC-MS to confirm the main compound to be guaiacol (2-methoxy phenol) in the range of 12–55% of oil depending on different reaction conditions. The most interesting was the finding that maximum value of total oil yield (10% of kraft lignin) and guaiacol amount (55% of oil) was obtained at 130ºC/15, 60 min which is a low reaction temperature/short time, while the residual kraft lignins were analyzed by FTIR with respect to the conversion mechanism of kraft lignin by this process.

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Catalytic converison of kraft lignin using paper-like Co(salen) as an effective catalyst

Gao T. T., Zhou X. F., Zhu Z. L.

Drewno : prace naukowe, doniesienia, komunikaty

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2015

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vol. 58, nr 195

79--90

EN

Co(salen) powders were homogeneously scattered over a ceramic fibre network to give a catalyst paper and the Co(salen) paper was tested for the oxidative degradation of a kraft lignin using H2O2 as an oxidant. Due to the structural effect of the interconnected 3D-network, the catalyst paper exhibited a higher performance in the oxidation of kraft lignin with a oil yield of 23.27 % than the original Co(salen) powder with an oil yield of 10.63 %, along with excellent recycling performance. 2,6-Dimethoxyphenol (2.32 mg/kg kraft lignin), vanillin (3.80 mg/kg kraft lignin), and syringaldehyde (2.63 mg/kg kraft lignin) were found to be the main products in the oil obtained. In addition, the structural changes in the kraft lignin were also studied during the process. The phenolic compounds were formed through side chain oxidation together with the oxidative cleavage of β-O-4 linkage.