Exploitation of olive tree pruning biomass through hydrothermal pretreatments

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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