Natural dyes have become an interesting subject of study because of their better ecological properties in comparison to their synthetic counterparts.This article concerns the dyeing of wool,silk,and polyamide fabrics ...Natural dyes have become an interesting subject of study because of their better ecological properties in comparison to their synthetic counterparts.This article concerns the dyeing of wool,silk,and polyamide fabrics with natural dyes extracted from almond shells and stems.The developed method of dyeing by these extracts is interesting and very attractive for several reasons:firstly,the extracts used are the black liquor discharged from the industries of delignification,which is a chemical process for removing lignin from agricultural wastes to produce a cellulosic fiber;(ii)these natural dyes are renewable and available in large quantities;(iii)this method is economical;and(iv)lastly,the dyeing performances of the obtained dyed textiles are very promising.The color of each dyed material was investigated in terms of the CIELAB coordinates and their fastness properties measured by washing,rubbing,and light.展开更多
Bio-based polyurethanes(PUs)have been occurred a large attention nowadays.It was found to be an alternative to the petrochemical based materials to the fact of their weak environmental influence,availability,good pric...Bio-based polyurethanes(PUs)have been occurred a large attention nowadays.It was found to be an alternative to the petrochemical based materials to the fact of their weak environmental influence,availability,good price and biodegradability.In addition,the nature shows several bio-derived compounds as raw materials for the synthesis of polyols,including the vegetable oils,polyphenol,terpene,and other bio-renewable sources.With the aim to develop a new family of biobased polyurethanes(PUs)via vegetable oils,the elaboration of new Jojoba-based PUs was performed by catalyst-free polycondensation reaction of a synthesized Jojoba diol with various diisocyanates such us toluene diisocyanate(TDI)and isophorone diisocyanate(IPDI).All the compounds were characterized by FTIR and NMR spectroscopies,and their properties were determined by gel permeation chromatography,differential scanning calorimetry and thermogravimetric analysis.The obtained results show renewable vegetable oils-based PUs materials can be preparing using a new environmentally ways and giving various good properties performances.展开更多
Alginate blended with cellulose nanocrystals(CNC),cellulose nanofibers(CNF),and tri-carboxylate cellulose nanofibers(TPC-CNF)prepared and encapsulated in the form of microcapsules(bio-polymeric beads).The cellulosic n...Alginate blended with cellulose nanocrystals(CNC),cellulose nanofibers(CNF),and tri-carboxylate cellulose nanofibers(TPC-CNF)prepared and encapsulated in the form of microcapsules(bio-polymeric beads).The cellulosic nanomaterials that used in this study were investigated as nanomaterials for wastewater treatment applications.Batch experiments were performed to study the removal of copper,lead,magnesium,and iron from aqueous solutions by the prepared beads.The effects of the sorbent dosage and the modified polymers on the removing efficiency of the metal cations were examined.Atomic absorption was used to measure the metal ions concentrations.The modified bio-polymeric beads(Alg-CNF,Alg-CNC,and Alg-TPC-CNF)exhibited high-efficiency towards removing of the metal cations;Cu^(2+),Pb^(2+),Mg^(2+),and Fe^(2+).The Alg-TPC-CNF composite was exhibited excellent removing efficiency which around 95%for Pb,92%for Cu,43%for Fe and 54%for Mg.These outcomes affirm that the utilization of nanomaterials giving higher adsorption capacities contrasted with similar material in its micro or macrostructure form.展开更多
The most abundant phenolic biopolymer in the biosphere is the lignin.This phenolic biopolymer commonly exists in combination with polysaccharides and other cell wall components.In this study,the solvent system dioxane...The most abundant phenolic biopolymer in the biosphere is the lignin.This phenolic biopolymer commonly exists in combination with polysaccharides and other cell wall components.In this study,the solvent system dioxane-water is used to extract lignin,which is considered as unaltered native lignin.The dioxane lignin extracted from fig stems was characterized regarding to its structural feature,quantification of its functional groups,molecular weight,and evaluation of its thermal properties.Purity and molecular weight distribution of the studied lignin indicated that isolated lignin contained a low amount of sugar(c.a.19%)and had a high weight-average molecular weight(10068 g.mol-1).Lignin sample had approximately the same amounts of guaiacyl(G)and p-hydroxyphenyl(H)units with relatively fewer syringyl(S)units.The isolated lignin revealed good antioxidant properties.Therefore,it proved to have a high potential of application in new antioxidants formulations.展开更多
Cellulose nanocrystal(CNC)is a biomaterial derived from plant lignocellulosic components,widely applied in various industrial fields.Concurrently,with the growth of awareness in developing green nanomaterial,the explo...Cellulose nanocrystal(CNC)is a biomaterial derived from plant lignocellulosic components,widely applied in various industrial fields.Concurrently,with the growth of awareness in developing green nanomaterial,the explored Washingtonia fibre could be alternative biomass for obtaining CNC products.In the present work,different acid concentrations of 5%,15%,and 25%hydrochloric solutions were employed to produce CNCs from Washingtonia fibre.With the chemical treatments,the yield of the CNC product was successfully retained at 21.6%-25.1%.Individually separated and needle-shaped CNC particles could be observed under the microscopic viewing with the increased acid concentrations.From elemental analysis,a relatively pure cellulose compartment was produced for all CNC samples.The zeta potential values between-10 to-16 mV proved that each nanoparticle sample possessed dispersion ability within an aqueous solution.Meanwhile,the degree of crystallinity and the thermal behavior of CNCs were enhanced with the increased acidic concentrations.Hence,the isolated CNCs(with 15%)from Washingtonia fibre lead a CNC with the highest aspect ratio(30).This parameter is so important that these structures show empowering points of view as nanomaterials for reinforced polymer composites,and it could be a reliable nano-filler for the composite fabrication process in the future.展开更多
The exploitation of biomass represents a major environmental challenge related to the protection of the environment and the progressive exhaust of fossil resources.In this perspective,the main objective of this work i...The exploitation of biomass represents a major environmental challenge related to the protection of the environment and the progressive exhaust of fossil resources.In this perspective,the main objective of this work is the extraction and the characterization of natural lignocellulosic fibers from the Schinus molle.The cellulose fibre extraction was investigated employing conditions of alkali treatment.After the alkaline steps,a bleaching treatment was done and let to a yield about 45%pure cellulose.The identification of the chemical composition of Schinus molle reveals that this raw material contains a high level of biopolymers with a cellulose rate of 53.2%.Extracted cellulose fibers have been characterized by several techniques such as scanning electron microscopy,Fourier transform infrared,X-ray diffraction,Morfi,and by the determination of their degree of polymerization.FT-IR results confirm the purity of the cellulosic fibers,and XRD analysis reveals that the crystallinity increases after the delignification and bleaching treatments.展开更多
Sodium carboxymethylcellulose (CMCNa) is an anionic water soluble polyelectrolyte widely used in many industrial sectors including food, textiles, papers, adhesives, paints, pharmaceuticals, cosmetics and mineral pr...Sodium carboxymethylcellulose (CMCNa) is an anionic water soluble polyelectrolyte widely used in many industrial sectors including food, textiles, papers, adhesives, paints, pharmaceuticals, cosmetics and mineral processing. CMCNa was produced by chemical modification of cellulose, and represents many advantages: natural, renewable, non-toxic and biodegradable. In this study, different kinds of CMCNa, prepared from an agricultural waste date palm rachis, were tested as eco-friendly flocculants for drinking water treatment and their performances as flocculants in turbidity removal enhancement were assessed. The prepared materials were characterized by the degree of substitution (DS) and polymerisation (DP). The study of the effect of some experimental parameters on the coagulation-flocculation performance, using the prepared materials combined with aluminium sulphate (as coagulant), showed that the best conditions for turbidity treatment were given for pH 8, coagulant dose 20 mg/L, flocculant concentration of 100 mg/L and stirring velocity (during the flocculation step) of 30 r/min. Under the optimum conditions, the turbidity removal using CMCNa, prepared from raw material, was about 95%. A comparison study between the flocculation performance of a commercial anionic flocculant (A100PWG: polyacrylamide) and that of the prepared CMCNa showed that the performance of the waste-based flocculant with a DS of 1.17 and a DP of 480 was 10% better than that achieved by the commercial one.展开更多
文摘Natural dyes have become an interesting subject of study because of their better ecological properties in comparison to their synthetic counterparts.This article concerns the dyeing of wool,silk,and polyamide fabrics with natural dyes extracted from almond shells and stems.The developed method of dyeing by these extracts is interesting and very attractive for several reasons:firstly,the extracts used are the black liquor discharged from the industries of delignification,which is a chemical process for removing lignin from agricultural wastes to produce a cellulosic fiber;(ii)these natural dyes are renewable and available in large quantities;(iii)this method is economical;and(iv)lastly,the dyeing performances of the obtained dyed textiles are very promising.The color of each dyed material was investigated in terms of the CIELAB coordinates and their fastness properties measured by washing,rubbing,and light.
基金the“CMPTM Project 17TM22”and to the“PHC-UTIQUE CMCU”(18G1132)the Tunisian Ministry of Higher Education and LabEx Tec 21 for the financial support.
文摘Bio-based polyurethanes(PUs)have been occurred a large attention nowadays.It was found to be an alternative to the petrochemical based materials to the fact of their weak environmental influence,availability,good price and biodegradability.In addition,the nature shows several bio-derived compounds as raw materials for the synthesis of polyols,including the vegetable oils,polyphenol,terpene,and other bio-renewable sources.With the aim to develop a new family of biobased polyurethanes(PUs)via vegetable oils,the elaboration of new Jojoba-based PUs was performed by catalyst-free polycondensation reaction of a synthesized Jojoba diol with various diisocyanates such us toluene diisocyanate(TDI)and isophorone diisocyanate(IPDI).All the compounds were characterized by FTIR and NMR spectroscopies,and their properties were determined by gel permeation chromatography,differential scanning calorimetry and thermogravimetric analysis.The obtained results show renewable vegetable oils-based PUs materials can be preparing using a new environmentally ways and giving various good properties performances.
基金The authors acknowledge the Science and Technology Development Fund(STDF),Egypt for financial support of the research activities related to the projectProject ID 15203+1 种基金The authors also gratefully express their sincere gratitude to the“PHC-UTIQUE CMCU”(18G1132)the CMPTM(17TM22),as well as to the Tunisian Ministry of Higher Education for the financial support.
文摘Alginate blended with cellulose nanocrystals(CNC),cellulose nanofibers(CNF),and tri-carboxylate cellulose nanofibers(TPC-CNF)prepared and encapsulated in the form of microcapsules(bio-polymeric beads).The cellulosic nanomaterials that used in this study were investigated as nanomaterials for wastewater treatment applications.Batch experiments were performed to study the removal of copper,lead,magnesium,and iron from aqueous solutions by the prepared beads.The effects of the sorbent dosage and the modified polymers on the removing efficiency of the metal cations were examined.Atomic absorption was used to measure the metal ions concentrations.The modified bio-polymeric beads(Alg-CNF,Alg-CNC,and Alg-TPC-CNF)exhibited high-efficiency towards removing of the metal cations;Cu^(2+),Pb^(2+),Mg^(2+),and Fe^(2+).The Alg-TPC-CNF composite was exhibited excellent removing efficiency which around 95%for Pb,92%for Cu,43%for Fe and 54%for Mg.These outcomes affirm that the utilization of nanomaterials giving higher adsorption capacities contrasted with similar material in its micro or macrostructure form.
文摘The most abundant phenolic biopolymer in the biosphere is the lignin.This phenolic biopolymer commonly exists in combination with polysaccharides and other cell wall components.In this study,the solvent system dioxane-water is used to extract lignin,which is considered as unaltered native lignin.The dioxane lignin extracted from fig stems was characterized regarding to its structural feature,quantification of its functional groups,molecular weight,and evaluation of its thermal properties.Purity and molecular weight distribution of the studied lignin indicated that isolated lignin contained a low amount of sugar(c.a.19%)and had a high weight-average molecular weight(10068 g.mol-1).Lignin sample had approximately the same amounts of guaiacyl(G)and p-hydroxyphenyl(H)units with relatively fewer syringyl(S)units.The isolated lignin revealed good antioxidant properties.Therefore,it proved to have a high potential of application in new antioxidants formulations.
基金This work is funded by Researchers Supporting Project number(RSP-2021/117)King Saud University,Riyadh,Saudi Arabia.The authors would like to thank the“PHC Utique”program of the French Ministry of Foreign Affairs and Ministry of Higher Education and Researchthe Tunisian Ministry of Higher Education and Scientific Research in the CMCU Project No.18G1132 for the financial support.
文摘Cellulose nanocrystal(CNC)is a biomaterial derived from plant lignocellulosic components,widely applied in various industrial fields.Concurrently,with the growth of awareness in developing green nanomaterial,the explored Washingtonia fibre could be alternative biomass for obtaining CNC products.In the present work,different acid concentrations of 5%,15%,and 25%hydrochloric solutions were employed to produce CNCs from Washingtonia fibre.With the chemical treatments,the yield of the CNC product was successfully retained at 21.6%-25.1%.Individually separated and needle-shaped CNC particles could be observed under the microscopic viewing with the increased acid concentrations.From elemental analysis,a relatively pure cellulose compartment was produced for all CNC samples.The zeta potential values between-10 to-16 mV proved that each nanoparticle sample possessed dispersion ability within an aqueous solution.Meanwhile,the degree of crystallinity and the thermal behavior of CNCs were enhanced with the increased acidic concentrations.Hence,the isolated CNCs(with 15%)from Washingtonia fibre lead a CNC with the highest aspect ratio(30).This parameter is so important that these structures show empowering points of view as nanomaterials for reinforced polymer composites,and it could be a reliable nano-filler for the composite fabrication process in the future.
基金the Tunisian Ministry of Higher Education and the“PHC Utique”Program of the French Ministry of Foreign Affairs and the Tunisian Ministry of Higher Education and Scientific Research(CMCU Project No.18G1132)as well as to CMPTM 17TM22 for the financial support.
文摘The exploitation of biomass represents a major environmental challenge related to the protection of the environment and the progressive exhaust of fossil resources.In this perspective,the main objective of this work is the extraction and the characterization of natural lignocellulosic fibers from the Schinus molle.The cellulose fibre extraction was investigated employing conditions of alkali treatment.After the alkaline steps,a bleaching treatment was done and let to a yield about 45%pure cellulose.The identification of the chemical composition of Schinus molle reveals that this raw material contains a high level of biopolymers with a cellulose rate of 53.2%.Extracted cellulose fibers have been characterized by several techniques such as scanning electron microscopy,Fourier transform infrared,X-ray diffraction,Morfi,and by the determination of their degree of polymerization.FT-IR results confirm the purity of the cellulosic fibers,and XRD analysis reveals that the crystallinity increases after the delignification and bleaching treatments.
基金supported by the Institute of Cooperation Francaise of the Embassy of France in Tunisia(IFC Tunisia)and by the Region Rhone Alpes(MIRA program)
文摘Sodium carboxymethylcellulose (CMCNa) is an anionic water soluble polyelectrolyte widely used in many industrial sectors including food, textiles, papers, adhesives, paints, pharmaceuticals, cosmetics and mineral processing. CMCNa was produced by chemical modification of cellulose, and represents many advantages: natural, renewable, non-toxic and biodegradable. In this study, different kinds of CMCNa, prepared from an agricultural waste date palm rachis, were tested as eco-friendly flocculants for drinking water treatment and their performances as flocculants in turbidity removal enhancement were assessed. The prepared materials were characterized by the degree of substitution (DS) and polymerisation (DP). The study of the effect of some experimental parameters on the coagulation-flocculation performance, using the prepared materials combined with aluminium sulphate (as coagulant), showed that the best conditions for turbidity treatment were given for pH 8, coagulant dose 20 mg/L, flocculant concentration of 100 mg/L and stirring velocity (during the flocculation step) of 30 r/min. Under the optimum conditions, the turbidity removal using CMCNa, prepared from raw material, was about 95%. A comparison study between the flocculation performance of a commercial anionic flocculant (A100PWG: polyacrylamide) and that of the prepared CMCNa showed that the performance of the waste-based flocculant with a DS of 1.17 and a DP of 480 was 10% better than that achieved by the commercial one.