Production of Cellulose Nanofibers from Olive Tree Harvest—A Residue with Wide Applications

With the aim of identifying new sources to produce cellulose nanofibers, olive tree pruning biomass (OTPB) was proposed for valorization as a sustainable source of cellulose. OTPB was subjected to a soda pulping process for cellulose purification and to facilitate the delamination of the fiber in the nanofibrillation process. Unbleached and bleached pulp were used to study the effect of lignin in the production of cellulose nanofibers through different pretreatments (mechanical and TEMPO-mediated oxidation). High-pressure homogenization was used as the nanofibrillation treatment. It was observed that for mechanical pretreatment, the presence of lignin in the fiber produces a greater fibrillation, resulting in a smaller width than that achieved with bleached fiber. In the case of TEMPO-mediated oxidation, the cellulose nanofiber characteristics show that the presence of lignin has an adverse effect on fiber oxidation, resulting in lower nanofibrillation. It was observed that the crystallinity of the nanofibers is lower than that of the original fiber, especially for unbleached nanofibers. The residual lignin content resulted in a greater thermal stability of the cellulose nanofibers, especially for those obtained by TEMPO-mediated oxidation. The characteristics of the cellulose nanofibers obtained in this work identify a gateway to many possibilities for reinforcement agents in paper suspension and polymeric matrices.

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Cellulose Nanofibers from a Dutch Elm Disease-Resistant Ulmus minor Clone

Polymers ◽

10.3390/polym12112450 ◽

2020 ◽

Vol 12 (11) ◽

pp. 2450 ◽

Cited By ~ 1

Author(s):

Laura Jiménez-López ◽

María E. Eugenio ◽

David Ibarra ◽

Margarita Darder ◽

Juan A. Martín ◽

...

Keyword(s):

Cellulose Nanofibers ◽

Barrier Properties ◽

Dutch Elm Disease ◽

Ulmus Minor ◽

Mechanical Pretreatment ◽

Pfi Refining ◽

First Time ◽

Mediated Oxidation ◽

Potential Use ◽

Selection Of

The potential use of elm wood in lignocellulosic industries has been hindered by the Dutch elm disease (DED) pandemics, which have ravaged European and North American elm groves in the last century. However, the selection of DED-resistant cultivars paves the way for their use as feedstock in lignocellulosic biorefineries. Here, the production of cellulose nanofibers from the resistant Ulmus minor clone Ademuz was evaluated for the first time. Both mechanical (PFI refining) and chemical (TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation) pretreatments were assessed prior to microfluidization, observing not only easier fibrillation but also better optical and barrier properties for elm nanopapers compared to eucalyptus ones (used as reference). Furthermore, mechanically pretreated samples showed higher strength for elm nanopapers. Although lower nanofibrillation yields were obtained by mechanical pretreatment, nanofibers showed higher thermal, mechanical and barrier properties, compared to TEMPO-oxidized nanofibers. Furthermore, lignin-containing elm nanofibers presented the most promising characteristics, with slightly lower transparencies.

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The Effect of Chemical and High-Pressure Homogenization Treatment Conditions on the Morphology of Cellulose Nanoparticles

Journal of Nanomaterials ◽

10.1155/2014/582913 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 7

Author(s):

Suxia Ren ◽

Xiuxuan Sun ◽

Tingzhou Lei ◽

Qinglin Wu

Keyword(s):

Thermal Stability ◽

High Pressure ◽

Acid Hydrolysis ◽

Cellulose Nanocrystals ◽

Cellulose Nanofibers ◽

High Pressure Homogenization ◽

Homogenization Treatment ◽

Cellulose Nanoparticles ◽

Nanofiber Bundles ◽

Thermal Stability Of

Cellulose nanoparticles were fabricated from microcrystalline cellulose (MCC) through combined acid hydrolysis with sulfuric and hydrochloric acids and high-pressure homogenization. The effect of acid type, acid-to-MCC ratio, reaction time, and numbers of high-pressure homogenization passes on morphology and thermal stability of the nanoparticles was studied. An aggressive acid hydrolysis was shown to lead to rod-like cellulose nanocrystals with diameter about 10 nm and lengths in the range of 50–200 nm. Increased acid-to-MCC ratio and number of homogenization treatments reduced the dimension of the nanocrystals produced. Weak acid hydrolysis treatment led to a network of cellulose nanofiber bundles having diameters in the range of 20–100 nm and lengths of a few thousands of nanometers. The high-pressure homogenization treatment helped separate the nanofiber bundles. The thermal degradation behaviors characterized by thermogravimetric analysis at nitrogen atmosphere indicated that the degradation of cellulose nanocrystals from sulfuric acid hydrolysis started at a lower temperature and had two remarkable pyrolysis processes. The thermal stability of cellulose nanofibers produced from hydrochloric acid hydrolysis improved significantly.

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Cellulose Nanofibers from Olive Tree Pruning as Food Packaging Additive of a Biodegradable Film

Foods ◽

10.3390/foods10071584 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1584

Author(s):

Mónica Sánchez-Gutiérrez ◽

Isabel Bascón-Villegas ◽

Eduardo Espinosa ◽

Elena Carrasco ◽

Fernando Pérez-Rodríguez ◽

...

Keyword(s):

Thermal Stability ◽

Food Packaging ◽

Cellulose Nanofibers ◽

Antioxidant Properties ◽

Water Vapor Permeability ◽

Olive Tree ◽

Barrier Properties ◽

Vapor Permeability ◽

Alternative Material ◽

Tree Pruning

A biodegradable packaging film containing cellulose nanofibers from olive tree pruning, a by-product of olives production, was obtained using a solvent casting method. Nanocellulose was added to polyvinyl alcohol (PVA) to enhance the technological properties of the composite film as food packaging material. Nanocellulose was obtained from unbleached and bleached pulp through a mechanical and TEMPO pretreatment. Crystalline and chemical structure, surface microstructure, UV and gas barrier, optical, mechanical and antioxidant properties, as well as thermal stability were evaluated. Regarding optical properties, the UV barrier was increased from 6% for the pure PVA film to 50% and 24% for unbleached and bleached nanocellulose, respectively. The antioxidant capacity increased significantly in unbleached mechanical nanocellulose-films (5.3%) compared to pure PVA film (1.7%). In terms of mechanical properties, the tensile strength of the 5% unbleached mechanical nanocellulose films was significantly improved compared to the pure PVA film. Similarly, the 5% nanocellulose films had increased the thermal stability and improved barrier properties, reducing water vapor permeability by 38–59% and presenting an oxygen barrier comparable to aluminum layer and plastic films. Our results support the use of the developed films as a green alternative material for food packaging.

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Analytical Characterization of Water-Soluble Constituents in Olive-Derived By-Products

Foods ◽

10.3390/foods10061299 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1299

Author(s):

Pablo Doménech ◽

Aleta Duque ◽

Isabel Higueras ◽

José Luis Fernández ◽

Paloma Manzanares

Keyword(s):

Olive Tree ◽

Mediterranean Area ◽

Water Soluble ◽

Olive Pomace ◽

Olive Leaves ◽

Olive Stone ◽

Olive Trees ◽

Tree Pruning ◽

By Products

Olive trees constitute one of the largest agroindustries in the Mediterranean area, and their cultivation generates a diverse pool of biomass by-products such as olive tree pruning (OTP), olive leaves (OL), olive stone (OS), and extracted olive pomace (EOP). These lignocellulosic materials have varying compositions and potential utilization strategies within a biorefinery context. The aim of this work was to carry out an integral analysis of the aqueous extractives fraction of these biomasses. Several analytical methods were applied in order to fully characterize this fraction to varying extents: a mass closure of >80% was reached for EOP, >76% for OTP, >65% for OS, and >52% for OL. Among the compounds detected, xylooligosaccharides, mannitol, 3,4-dihydroxyphenylglycol, and hydroxytyrosol were noted as potential enhancers of the valorization of said by-products. The extraction of these compounds is expected to be more favorable for OTP, OL, and EOP, given their high extractives content, and is compatible with other utilization strategies such as the bioconversion of the lignocellulosic fraction into biofuels and bioproducts.

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Production of Microfibrillated Cellulose from Fast-Growing Poplar and Olive Tree Pruning by Physical Pretreatment

Applied Sciences ◽

10.3390/app11146445 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6445

Author(s):

David Ibarra ◽

Raquel Martín-Sampedro ◽

Bernd Wicklein ◽

Úrsula Fillat ◽

María E. Eugenio

Keyword(s):

Negative Impact ◽

Raw Materials ◽

Olive Tree ◽

Barrier Properties ◽

Microfibrillated Cellulose ◽

Mechanical Resistance ◽

Fast Growing ◽

Wide Range ◽

Pfi Refining ◽

Tree Pruning

Motivated by the negative impact of fossil fuel consumption on the environment, the need arises to produce materials and energy from renewable sources. Cellulose, the main biopolymer on Earth, plays a key role in this context, serving as a platform for the development of biofuels, chemicals and novel materials. Among the latter, micro- and nanocellulose have been receiving increasing attention in the last few years. Their many attractive properties, i.e., thermal stability, high mechanical resistance, barrier properties, lightweight, optical transparency and ease of chemical modification, allow their use in a wide range of applications, such as paper or polymer reinforcement, packaging, construction, membranes, bioplastics, bioengineering, optics and electronics. In view of the increasing demand for traditional wood pulp (e.g., obtained from eucalypt, birch, pine, spruce) for micro/nanocellulose production, dedicated crops and agricultural residues can be interesting as raw materials for this purpose. This work aims at achieving microfibrillated cellulose production from fast-growing poplar and olive tree pruning using physical pretreatment (PFI refining) before the microfibrillation stage. Both raw materials yielded microfibrillated cellulose with similar properties to that obtained from a commercial industrial eucalypt pulp, producing films with high mechanical properties and low wettability. According to these properties, different applications for cellulose microfibers suspensions and films are discussed.

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Evaluation of lignins from side-streams generated in an olive tree pruning-based biorefinery: Bioethanol production and alkaline pulping

International Journal of Biological Macromolecules ◽

10.1016/j.ijbiomac.2017.07.030 ◽

2017 ◽

Vol 105 ◽

pp. 238-251 ◽

Cited By ~ 22

Author(s):

José I. Santos ◽

Úrsula Fillat ◽

Raquel Martín-Sampedro ◽

María E. Eugenio ◽

María J. Negro ◽

...

Keyword(s):

Olive Tree ◽

Bioethanol Production ◽

Alkaline Pulping ◽

Tree Pruning

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Comparative study of isotherm parameters of lead biosorption by two wastes of olive-oil production

Water Science & Technology ◽

10.2166/wst.2015.153 ◽

2015 ◽

Vol 72 (5) ◽

pp. 711-720 ◽

Cited By ~ 9

Author(s):

G. Blázquez ◽

A. Ronda ◽

M. A. Martín-Lara ◽

A. Pérez ◽

M. Calero

Keyword(s):

Experimental Data ◽

Olive Tree ◽

Langmuir Equation ◽

Equilibrium Isotherm ◽

Chemical Treatments ◽

Olive Stone ◽

Loss Of Mass ◽

Best Fit ◽

Tree Pruning ◽

Effectiveness Coefficient

Batch isotherm studies were carried out on a laboratory scale: (i) to investigate the effectiveness to remove lead of two wastes (olive stone (OS) and olive tree pruning (OTP)), untreated and chemically treated; and (ii) to examine the applicability of various adsorption isotherms to fit the experimental data. Results from tests were analyzed using seven equilibrium isotherm correlations (Langmuir, Freundlich, Dubinin–Radushkevich, Temkin, Redlich–Peterson, Sips, and Toth equations). The sum of the squares of the errors was determined for each isotherm and the Langmuir equation provided the best fit. Chemical treatments increased the biosorption properties of these materials. The maximum biosorption capacities were: 6.33, 49.13, 14.83, and 38.93 mg g−1 for untreated OS, HNO3-OS, H2SO4-OS, and NaOH-OS, respectively, and 26.72, 86.40, 72.78, and 123.80 mg g−1 for untreated OTP, HNO3-OTP, H2SO4-OTP, and NaOH-OTP, respectively. Finally, the loss of mass for each waste (13.9, 14.3, and 36.8% for HNO3-OS, H2SO4-OS, and NaOH-OS and 35.1, 27.5, and 46.7% for HNO3-OTP, H2SO4-OTP, and NaOH-OTP, respectively) was taken into account and an effectiveness coefficient was determined for each adsorbent material.

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