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Marrakchi Z.,LGP2 Laboratory of Pulp and Paper Science | Marrakchi Z.,Research Unity of Applied Chemistry and Environment | Oueslati H.,Research Unity of Materials Environment and Energy | Belgacem M.N.,LGP2 Laboratory of Pulp and Paper Science | And 2 more authors.
Composites Part A: Applied Science and Manufacturing | Year: 2012

To the best of our knowledge, this is the first report of combining alfa fibres with polycaprolactone (PCL) and using impregnation as a processing technique. Alfa fibres were used to prepare films that were impregnated with PCL solutions in order to produce composites in a continuous process. The resultant composites were studied by scanning electron microscopy, which showed that the PCL matrix formed continuous and homogeneous films. Dynamic mechanical analyses showed that the rubbery plateau of the virgin matrix was significantly prolonged. Differential scanning calorimetry showed that the crystallisation capacity of the PCL matrix increased with an increase in the reinforcing cellulose. Finally, the produced composites were assessed by performing contact angle measurements of a water droplet, and it was revealed that this parameter increased up to 130°, indicating that their wettability had decreased drastically. © 2012 Elsevier Ltd. All rights reserved.


Meksi N.,Research Unity of Applied Chemistry and Environment | Meksi N.,Higher Institute of Fashion of Monastir | Haddar W.,Research Unity of Applied Chemistry and Environment | Hammami S.,Research Unity of Applied Chemistry and Environment | Mhenni M.F.,Research Unity of Applied Chemistry and Environment
Industrial Crops and Products | Year: 2012

Olive mill wastewater (OMW) is a by-product of the olive oil extraction process. Around 30millionm3 of OMW are produced annually in the Mediterranean area, causing environmental concern. In spite of being a serious ecological problem, OMW can represent a possible resource for the dyeing of textile materials. It contains a valuable source of abundant natural colouring substances. The present study reports the valorization of OMW by its use as a possible dyebath for dyeing wool. It was found that protein fibers possess high affinity to the aqueous extract of OMW giving darker shades with generally good fastnesses. The effect of dyebath pH, dyebath temperature, dyeing time and salt addition on the dyeability of wool were investigated. The effect of mordant type with different mordanting methods on dyeing quality was also studied. The results showed that mordanting gave deeper shades and enhanced fastness properties. © 2012 Elsevier B.V.


Khiari R.,CNRS Structural Engineering | Khiari R.,Research Unity of Applied Chemistry and Environment | Mauret E.,CNRS Structural Engineering | Belgacem M.N.,CNRS Structural Engineering | Mhemmi F.,Research Unity of Applied Chemistry and Environment
BioResources | Year: 2011

Every year, significant amounts of date palm rachises are accumulated in Tunisia. The rational valorisation of this renewable resource is therefore imperative, in order to fulfil the sustainability approach. In this context, this work aims to study the potential use of date palm rachises as a raw material for papermaking and to compare it with other sources of lignocellulosic fibres, such as wood, non-wood species, and agricultural wastes. For this purpose, soda-anthraquinone pulping of date palm rachis was performed giving rise to a yield of 45% (w/w). This value is similar to that obtained by pulping non-wood materials and is higher than that corresponding to the pulping of agricultural residues. The resulting pulps were subsequently refined using a PFI mill refiner at 0, 500, 1500, and 3000 revolutions, screened through a 0.15 mm mesh size sieve and used to produce conventional handsheets. Both pulps and papers were fully characterized in terms of morphological, chemical and physical properties, according to commonly used standards. The physical properties of the prepared handsheets were very similar to those displayed by other papers made of common lignocellulosic fibres. Furthermore, the pulps exhibited a good drainability together with excellent mechanical properties of the ensuing papers. For these reasons, date palm rachises could be considered as a potential source of fibres for papermaking applications.


Ramzi K.,CNRS Structural Engineering | Ramzi K.,Research Unity of Applied Chemistry and Environment | Nizar M.,Research Unity of Applied Chemistry and Environment | Farouk M.,Research Unity of Applied Chemistry and Environment | And 2 more authors.
Fibers and Polymers | Year: 2011

The chemical composition of date palm rachis wastes, which are widely available cellulosic biomass-based agricultural crops in Tunisia, were characterized to determine if they had the potential for use as a starting raw material to prepare cellulose derivatives. To accomplish this, several sodium cellulose carboxylmethylates (NaCMCs) were prepared and tested as sizing agents for coating yarn. The synthesis of NaCMC was conducted in n-butanol containing NaOH (40 %) as a solvent mixture and monochloroacetic acid (MAC) as the etherifying reagent. The NaCMC samples were characterized based on their degrees of substitution (DS) and polymerization (DP). The prepared NaCMC samples were then tested as sizing agents for cotton yarn in textile applications. Specifically, different NaCMC samples were used to prepare a coating bath, which was then applied to size a cotton yarn textile. The quality of the coated yarns was subsequently evaluated by determining three parameters, yarn hairiness, the load at break, and the elongation at break. The sizing performances of the NaCMCs prepared from date palm rachis wastes were then compared with those of commercial NaCMC. The values of hairiness, breaking load, and breaking elongation of some of the NaCMC-treated yarns were as high as those prepared using commercial additives as sizing agents. These findings indicate that the cellulose derivatives prepared in this study are good candidates for alternatives to currently available additives. © 2011 The Korean Fiber Society and Springer Netherlands.


Marrakchi Z.,CNRS Structural Engineering | Marrakchi Z.,Research Unity of Applied Chemistry and Environment | Khiari R.,CNRS Structural Engineering | Khiari R.,Research Unity of Applied Chemistry and Environment | And 3 more authors.
Industrial Crops and Products | Year: 2011

The objective of this work is to study characteristics of chemical pulps (soda cooking process) and of paper obtained from Alfa, also known as Stipa tenacissima. For this purpose, Tunisian Alfa stems, and both unbleached and bleached pulps were characterized by determining their chemical composition as well as their morphological and physical properties. Through a detailed comparison with the other pulps obtained from various species, we show that the properties of Alfa stem fibres are intermediate between those of non-wood and wood plants, and most often close to those of Eucalyptus fibres. Refining process (PFI mill device) was then applied to the unbleached and bleached Alfa pulps. The modifications of the morphological properties of the fibres and the drainability and water retention values of the pulps were studied as a function of the refining degree. Here again, Alfa fibres exhibit a behaviour similar to that of Eucalyptus fibres, as the fibre shortening is very limited during the refining process. Finally, conventional handsheets with a basis weight of 65g/m2 were prepared from the unrefined and refined pulps. Their characterization showed that Alfa based papers present low density values and quite good mechanical properties, which are significantly enhanced by the refining treatment, particularly for the unbleached pulp. This study demonstrates the high potentiality of this non-wood species for papermaking applications. © 2011 Elsevier B.V.


Khiari R.,CNRS Structural Engineering | Khiari R.,Research Unity of Applied Chemistry and Environment | Marrakchi Z.,CNRS Structural Engineering | Marrakchi Z.,Research Unity of Applied Chemistry and Environment | And 3 more authors.
Composites Science and Technology | Year: 2011

In this work, new lignocellulosic particles obtained from Posidonia oceanica were studied to reinforce a commercial biodegradable thermoplastic matrix. First, these reinforcing fillers were characterised by Fourier-transform infrared (FT-IR) and X-ray photoelectron (XPS) spectroscopies. Then, they were used to prepare several composite films using BIOPLAST GF 106 matrix. Different P. oceanica fragment loadings, namely 0%, 10%, 20% and 30% (w/w with respect to the matrix) were investigated. The morphology of the ensuing materials was assessed by scanning electron microscopy (SEM), whereas their thermal and mechanical properties were studied by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and tensile tests. The obtained results showed that P. oceanica-based particles enhanced the thermo-mechanical properties of the thermoplastic matrix. © 2011.


Khiari R.,Research Unity of Applied Chemistry and Environment | Khiari R.,CNRS Structural Engineering | Mhenni M.F.,Research Unity of Applied Chemistry and Environment | Belgacem M.N.,CNRS Structural Engineering | Mauret E.,CNRS Structural Engineering
Bioresource Technology | Year: 2010

In the present paper, the valorisation of two residues: Posidonia oceanica and date palm rachis was investigated. First, their chemical composition was studied and showed that they present amounts of holocellulose, lignin and cellulose similar to those encountered in softwood and hardwood. Extractives in different solvents and ash contents are relatively high. Moreover, ash composition assessment showed that silicon is the major component (17.7%) for P. oceanica. The high ash quantity and the low DP (about 370) may be considered as serious disadvantages of P. oceanica, in the pulping and papermaking context. Oppositely, the properties of rachis date palm and those of the ensuing pulp, obtained from a classical soda-anthraquinone cooking, demonstrated the suitability of this agricultural by-product for papermaking. Preliminary tests conducted on unrefined pulp suspensions and handsheets from date palm rachis in terms of freeness, Water Retention Value and mechanical properties allowed confirming the good quality of date palm rachis fibres. © 2009 Elsevier Ltd. All rights reserved.


Khiari R.,Research Unity of Applied Chemistry and Environment | Khiari R.,CNRS Structural Engineering | Mhenni M.F.,Research Unity of Applied Chemistry and Environment | Belgacem M.N.,CNRS Structural Engineering | Mauret E.,CNRS Structural Engineering
Journal of Polymers and the Environment | Year: 2011

Different qualities of CMC were prepared from an agricultural residue (date palm rachis) and a marine waste (Posidonia oceanica). These starting lignocellulosic materials were used as such and after chemical pulping and bleaching. The carboxymethylation reaction was carried out in presence of NaOH (40%) and monochloroacetic acid (ClCH 2COOH, MAC), in n-butanol as the reaction solvent. The substitution degrees (DS) of the obtained CMCs varied from 0.67 to 1.62 and between 0.98 and 1.86, for P. oceanica and date palm rachis, respectively. The CP-MAS 13C-NMR spectra of the prepared polyelectrolytes displayed the presence of the main peaks associated with cellulose macromolecules (C1-C6) and that corresponding to carboxyl functions at around 175 ppm. Unfortunately, the peak attributed to methylene groups neighbouring carboxyl moieties are overlapped by C2 and C3, which renders them hardly detectable. Nevertheless, it is worth noting that the CP-MAS 13C-NMR spectra revealed the presence of different signals originating from residual impurities (ca. 27 ppm), such as traces of lignin macromolecules (110-150 ppm) and methyl groups attributed to hemicelluloses. Work is in progress to establish a more efficient purification procedure, in order to have more accurate values of DS. © 2010 Springer Science+Business Media, LLC.


Khiari R.,Research Unity of Applied Chemistry and Environment | Dridi-Dhaouadi S.,Research Unity of Applied Chemistry and Environment | Aguir C.,Research Unity of Applied Chemistry and Environment | Mhenni M.F.,Research Unity of Applied Chemistry and Environment
Journal of Environmental Sciences | Year: 2010

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. © 2010 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences.


Ramzi K.,Research Unity of Applied Chemistry and Environment | Ikhlass F.,Research Unity of Applied Chemistry and Environment | Farouk M.M.,Research Unity of Applied Chemistry and Environment
Fibers and Polymers | Year: 2010

The Posidonia is a sea plant which is abundant on the Tunisian coasts. Important quantities of Posidonia oceanica fragments are accumulated every year on the beaches which must be cleaned every summer. This plant contains an important ratio of cellulosic materials. On other hand, local sanitary articles industry use important quantities of absorbing materials. The aim of this work is to take advantage of this available biomass by using it as a raw material for the preparation of some of these absorbing materials. In this aim three cellulose qualities of various purities are prepared starting from Posidonia wastes and from these three cellulosic materials six qualities of sodium carboxymethylcellulose (CMCNa) are synthesised, these qualities differ by there substitution degree. The performances of all these materials are evaluated in term of absorption and retention capacities. With this end in view, three kinds of liquids are used: the deionized water, the synthetic urine and the salt solution. Then the evaluated performances are compared with those of some commercial absorbent materials used in local industries (industrial cellulosic pulp and superabsorbant). This comparison shows that the different prepared CMCNa have a retention capacity largely higher than those of the commercial cellulosic pulp. The difference can reaches 405 %. The evaluated absorption capacities of all the prepared CMCNa are generally similar to those of the commercial cellulosic pulp. However the tested superabsorbant presents, in all cases, the best performances in term of liquid absorption and retention. © 2010 The Korean Fiber Society and Springer Netherlands.

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