Argan Shells Research Articles

Design of nanoemulgel using Argania spinosa microfibrillated cellulose and natural emulsifiers foreseeing melanogenesis enhancement

Nanotechnology is a route of choice that improves administration and efficacy of bioactive compounds. In this study, nanoemulgels were prepared using microfibrillated cellulose from Argania spinosa shell (AS-MFC) and Argan shell (ASE) or Argan press cake extracts (APC) as natural emulsifiers. Oil-in-water (O/W) nanoemulsions were prepared using different natural emulsifiers or synthetic emulsifiers and presented a nano size (d3,2 < 140 nm). Following that, the nanoemulsions were incorporated within AS-MFC matrix and rheological properties confirmed a shear thinning behavior. Confocal micrographs of nanoemulgels confirmed the dispersion of nanoemulsions in the AS-MFC network without affecting the nanoemulsions stability. Finally, in vitro bioassay on B16F10 using ASE or APC nanoemulsions was conducted. This study confirmed cell permeation in B16F10 cells of formulated nanoemulsions and the upregulation of melanin content up to 30% more that the untreated cells. This study designed novel MFC nanoemulgel with high potential application in healthcare and cosmetic field.

Antioxidant Additives Produced from Argan Shell Lignin Depolymerization

The present work summarizes the results of an experimental study focused on producing antioxidant additives for biofuels from argan shell lignin. The generation of this waste has noticeably increased in specific regions of Morocco as a result of the upward trend in the production of argan oil. Lignin extracted from argan shells via a semi-chemical pulping process was depolymerized under hydrothermal conditions in a stirred autoclave reactor at a temperature range of 250–350 °C. Lignin conversion to phenolic compounds was conducted in subcritical water together with different reaction medium (H2, CO2, and HCOOH). The organic fraction in the aqueous liquid product was extracted and blended with biodiesel at a dosage of 1 wt % to evaluate its antioxidant potential. According to the obtained results, the biodiesel oxidation stability time was drastically improved up to 400%. The depolymerization temperature was observed as a critical factor in the antioxidant potential of the additives, showing a maximum value at 300 °C, regardless of the reaction medium. An extensive characterization of the produced additives was performed. The phenolic monomers present in the produced additives were identified using gas chromatography–mass spectrometry, finding a notable presence of catechol, especially in the additives obtained at 300 °C, which led to the best results of biodiesel oxidation stability. Gel permeation chromatography analyses of the additives also showed a well dissolution of relatively big molecules (up to 7000 Da) in biodiesel. More efforts are required to verify the actual antioxidant potential of these types of molecules.

Upgrading Argan Shell Wastes in Wood Plastic Composites with Biobased Polyethylene Matrix and Different Compatibilizers.

The present study reports on the development of wood plastic composites (WPC) based on micronized argan shell (MAS) as a filler and high-density polyethylene obtained from sugarcane (Bio-HDPE), following the principles proposed by the circular economy in which the aim is to achieve zero waste by the introduction of residues of argan as a filler. The blends were prepared by extrusion and injection molding processes. In order to improve compatibility between the argan particles and the green polyolefin, different compatibilizers and additional filler were used, namely polyethylene grafted maleic anhydride (PE-g-MA 3 wt.-%), maleinized linseed oil (MLO 7.5 phr), halloysite nanotubes (HNTs 7.5 phr), and a combination of MLO and HNTs (3.75 phr each). The mechanical, morphological, thermal, thermomechanical, colorimetric, and wettability properties of each blend were analyzed. The results show that MAS acts as a reinforcing filler, increasing the stiffness of the Bio-HDPE, and that HNTs further increases this reinforcing effect. MLO and PE-g-MA, altogether with HNTs, improve the compatibility between MAS and Bio-HDPE, particularly due to bonds formed between oxygen-based groups present in each compound. Thermal stability was also improved provided by the addition of MAS and HNTs. All in all, reddish-like brown wood plastic composites with improved stiffness, good thermal stability, enhanced compatibility, and good wettability properties were obtained.

Thermal conductivity of clay based material incorporating Argan Shell: Experimental characterization

This research investigated the impact of agricultural biomass additives (Argan shell) on the thermal and physical properties of fired clay bricks for building application. The objective of the study is to characterize the selected materials from molecule up to the final materials used in buildings. The materials used in this study, are soil and Argan shells, locally available materials for brick making. The Argan shells were grinded and then added to the clay mixture. The Clay brick shows a formation of pores during the firing process up to 1050°C. As results, the bulk density of the clay bricks decreased due to the pores formation. On the other hand, the thermal conductivity of the clay bricks was reduced by 53% using 20wt% of the biomass additives.

Microfibrillated cellulose from Argania spinosa shells as sustainable solid particles for O/W Pickering emulsions

Microfibrillated cellulose (MFC) from Argan (Argania spinosa) shells was prepared by chemical purification of cellulose, then mechanical disintegration via high pressure homogenization was performed to isolate fibrils of cellulose. Chemical characterization of raw argan shell (AS-R), purified cellulose (AS-C), and argan shell MFC (AS-MFC) included FT-IR, XRD and NMR. Morphological characterization of AS-MFC was assessed using TEM. Next, the use of AS-MFC as oil-in-water (O/W) emulsions stabilizer was investigated. The particle concentration was observed to affect the long-term stability of the emulsions; high concentrations (0.5–1 % w/w) of AS-MFC resulted in emulsions that were thermodynamically stable during 15 days of storage, which was demonstrated by the droplet’s size evolution. The suitable oil concentration for a maximum volume of emulsion using 1 % w/w AS-MFC was demonstrated. The results show that AS-MFC is able to stabilize 70 % w/w MCT oil without visual phase separation. Finally, CLSM shows the adsorption of AS-MFC at the oil-water interface and the formation of a 3D network surrounding oil droplets, confirming Pickering emulsion formation and stabilization.

Mechanical properties of poly–propylene reinforced with Argan nut shell aggregates: Computational strategy based microstructures

This paper aims at developing 3D numerical simulations of the mechanical properties of polymer composites based on the aggregates of argan shell. The microstructure is made up of two phases, corresponding to the Poly–Propylene PP matrix and the natural aggregates. Due to the grinding operation of agran shell during the manufacturing process, the aggregates shapes, crushed aggregates, greatly vary with their surfaces. The majority of published works used the spherical or ellipsoidal forms in order to study numerically the mechanical behavior of such composites, because of the inherent simplification in algorithm formulations. However, real microstructures of these composites based simple microscopic, show that the shape of aggregates does not takes a spherical form, but a polyhedral form. In this study, the microstructure is described and modeled as a combination of Poisson polyhedral and PP matrix. In the numerical model, the obtained aggregate morphology is similar to that of many argan shell powders often used as reinforcement of the PP matrix. This technique allows generating models with different reinforcement volume fractions up to 28%. The numerical homogenization technique is used to estimate the mechanical properties of these composites. The set obtained numerical results with 3D polyhedral model are compared with the pertinent experimental data and analytical models reported in the literature. The performance of the most used micromechanical schemes used in predicting the effective elastic properties of biocomposites was discussed.

Formation and stability of emulsions using crude extracts as natural emulsifiers from Argan shells

This study evaluated the emulsifying performance of five aqueous-ethanolic argan shell (Argania spinosa L.) crude extracts. We aim to compare crude extracts originating from the same raw material to produce stable oil-in-water (O/W) emulsions. First, surface-active compounds (i.e. saponins, proteins, and polyphenols) were quantified and interfacial tension against soybean oil of the extracts was assessed. We report here that despite the variation in the composition, the crude extracts were capable of similarly reducing the interfacial tension at the soybean oil/water interface to an average of 11 mN/m. Nevertheless, when comparing oil droplets formation, the volume mean droplet size varied within extracts 200 nm ≤ d4,3≤ 440 nm. The emulsions were stable for 30 days at two temperatures 5 ℃ and 25 ℃ with high negative charge −46.3 mV ≤ζ -potential ≤ −51.5 mV. The stabilization mechanism is attributed to the synergic effect of surface-active compounds found in the bulk phase. The whole composition of crude extracts contributes to the overall emulsifying performance. Besides, protein and proteins-saponins complexes, adsorbing to the interface, provide electrostatic and steric repulsions that enhance the stability of emulsions.

A high energy storage supercapacitor based on nanoporous activated carbon electrode made from Argan shells with excellent ion transport in aqueous and non-aqueous electrolytes

Abstract A high-performance supercapacitor electrode was obtained from waste biomass, Argan shells. This electrode was fabricated using a simple activation technique; demonstrating an industry-friendly process, which is capable of having precise control over pore size distribution of the activated carbon derived from a natural resource. The obtained samples exhibited different pore size distributions, based on different activating agents and different activation routes used in the process. Two distinctly different pore size distributions were obtained from a single source and same synthesis routes, only by exploiting the size differences of the activating agents, which are potassium (KOH) and sodium (NaOH) ions respectively. This process enabled a significant enhancement of specific energy, with no or very negligible change in specific power. Thanks to the fact that there was almost no loss in ion diffusion properties within the porous network of the electrodes even after a change in the electrolytes, to the more viscous ionic liquid (Ethyl-Methyl Imidazolium Tetrafluoroborate), from comparatively less viscous aqueous and organic-based electrolytes. This size-controlled activation enabled us obtaining appropriate pore size distribution, which is a combination of a large number of micropores and a sufficient number of mesopores. This provided a very high specific surface area of 2251 m2/g with a total pore volume of 1.04 cm3/g. Very high specific capacitance of ∼179 F/g in aqueous electrolyte (0.5 M K2SO4) was obtained. The excellent porosity resulted in very high specific energy of ∼65 Wh/kg and high specific power of ∼2 kW/kg in ionic liquid electrolyte for 3.5 V operating voltage.

Non-isothermal kinetic analysis of the combustion of argan shell biomass

Abstract Argan shell is one of the main by-products during argan oil production. It is considered as an attractive, cheap and renewable biomass source for sustainable energy utilization. The present paper reports on combustion characteristics of argan shell in order to evaluate their potential for thermochemical conversion. Combustion studies using thermogravimetry (TG) are performed at four different heating rates of 5, 10, 15 and 20 °C·min−1. Kinetic parameters under non-isothermal condition are calculated using FWO (Flynn-Wall-Ozawa method) and KAS (Kissinger-Akahira-Sunose) model free methods. From the results obtained, it was revealed that when the conversion level (α) fluctuates between 0.1 and 0.55, the average activation energy were 154 and 145 KJ/mol for FWO and KAS methods, respectively. Then, it decreases drastically with α ≥ 0.6, reflecting the kinetic complexity of the combustion process characterized by a faster reaction caused by the intense devolatilization stage. Overall, the results highlight the potential use of argan shell as a biomass product for thermal conversion through combustion.

Thermo-physical analysis of low-cost ecological composites for building construction

The building sector is one of the highest energy consumers in the world, driving the scientific community to find different alternatives for solving the problem. The choice of suitable materials represents a considerable challenge for enhancing thermal comfort in buildings. In the present study, new composite samples based on locally available materials are manufactured and experimentally evaluated in order to obtain low-cost ecological materials with better thermo-physical properties. The composites are intended to be used in building walls. They are mainly cement-stabilized red clays (CSRC) with incorporation of different kind of natural and industrial insulators. Red clay is presented as material with high thermal performance. Natural wastes are of great importance owing to their low-cost and environment-friendly nature. Thermal conductivity and thermal diffusivity measurements are carried out using Hot Disk thermal analyzer. Combined with the density data, thermal capacity is calculated. The results of the investigation show that the thermal performance of a building material can be improved by using red clay as basic material instead of sand, and incorporating thermal insulators. The thermal conductivity of cement-stabilized sand (0.934 W/m K) is greater than cement-stabilized clay (0.591 W/m K), which becomes lower when incorporating polystyrene (0.591 W/m K). The CSRC incorporating sawdust, petiole, straw, Argan shell, and palm fibers offer interesting thermal performance in comparison to ordinary concretes, with an average thermal capacity and conductivity of respectively 1120 kJ/m3 K and 0.43 W/m K. Additionally, it is revealed that the thermal conductivity is mostly affected by cement content, humidity and temperature. By varying the cement content of stabilized clay (from 5% to 20%), the thermal conductivity increases by about 39%. For an average water content ranging between 1.2% and 12.9%, it increases by 74%. An increase of about 10% in conductivity is recorded between room temperature and 50 °C. Finally, comparing the results, the CSRC incorporating Argan shell is considered as the best building material in this study.

Removal of Cationic Dye from Aqueous Solution Using Agricultural Wastes: Argan and Almond Shells

In this work, Crystal Violet (CV), cationic dye, is removed from aqueous solution, using wood of Argan shell(ARS) and Almond shell (ALS), as low-cost and eco-friendly biosorbants. The parameters influencing the adsorption of CVon each of our adsorbents, contact time (5–180 min), adsorbent dose (0.2–2 g), pH of the solution (3–11), temperature (20–50°C) and the initial dye concentration (50–500 mg.L-1), were studied.The modeling of experimental results obtained, shows that the CV adsorption on both biomaterials follows a pseudo-second-order kinetic and in perfect agreement with Langmuir isotherm. Also CV is better adsorbed on ALS that ARS, with maximum biosorption amounts 51.99 mg.g-1 and 37.32mg.g-1, respectively, at 40 ° C. Thermodynamic calculations have shown that the sorption is spontaneous, endothermic and random at the solid / solution interface. Adsorption capacities of dyes by ARS and ALS are better or comparable to those of several other biomaterials already studied.ALS and ARS biomaterials studied can be considered as alternative biosorbants low-cost and eco-friendly..

Characterization of pyrolysis products derived from three biological wastes and their effect on plant growth and soil water retention

Over two-thirds of Morocco can be classified as semiarid, arid and desert with low and variable rainfalls. While the country is subject to frequent drought, groundwater resources are predominantly consume by irrigated agriculture leading to the depletion of water resources and degradation of soil quality. Application of bio-resources wastes to soils after pyrolysis process is well documented to help retain water and nutrients in soils. In this study, three bio-resources wastes derived from argan shells, wood chip, a blend of paper sludge and wheat husks are characterized for physical and chemical properties. To determine the potential impact of salt stress and toxic substances the second part of this study focused on the effect these bio-resources wastes have on germination of salad and barley respectively. The three bio-resources obtained from different biomass showed some unique properties compared to the soil, such as high electrical conductivity (EC), high content of K, Na and Mg, low content of heavy metals. Moreover, the water holding capacities increased with increasing application of bio-resources wastes. Concerning the phytotoxic tests, no negative effect was observed neither for salad (Lactuca sativa L.) nor for barley (Hordeum vulgare) indicating that the three bio-resources could be safely used for agriculture. Collectively, the use of these bio-resources wastes as a soil amendment is anticipated to increase both water and nutrient and could provide the potential for a better plant growth mainly in semiarid, arid and desert climatic conditions like the case of Morocco in which the agricultural practices reserve a majority of the water resources to be used for irrigation.

Phytotoxic effects of argan shell biochar on salad and barley germination

Biochar produced from argan shells can be contaminated by toxic substances accumulated during the pyrolysis process. To determine the potential impact of toxic substances and salt stress, this study focused on the effect argan shell biochar had on the germination of salad (0%, 0.5%, 1%, 2%, 4% or 8% biochar dry weight in a sand-biochar mixture) and barley seeds (0%, 1%, 2.5%, 5% or 10% biochar dry weight in a peat-biochar mixture). No negative salt stress effect of argan biochar on the germination of salad was observed nor on the germination rate and fresh weight of seedlings. Additionally, biochar application increased the germination rate and the fresh biomass weight in all of the treatments. No significant difference was observed from the control with the barley germination rate, fresh and dry weights of barley seedlings, water content and water use efficiency of different mixtures (peat-biochar). Thus, for both the salad and barley germination tests, no negative effects of biochar produced from argan shells were identified, providing a preliminary indication that it could be safely used for agriculture.

Synthesis of hard carbon from argan shells for Na-ion batteries

Higher reversible capacity of 333 mA h g−1 in Na cell is demonstrated for hard carbon derived from HCl-treated argan.

Biochar from argan shells: production and characterization

The agricultural practices in south western Morocco reserve a majority of the water resources to be used for irrigation. The extent of irrigated agriculture combined with high evaporative rates, lead to the depletion of water resources and degradation of soil quality. To remedy to this problem, biochar, a pyrolysed biomass, is highly considered to improve retaining water and nutrients in soils. For this biochar research, argan shells obtained after extraction of argan oil were used as the biomass source to produce biochar. According to the best of our knowledge, no research to date has been carried out on the production and characterization of biochar produced from argan shells wastes. To produce biochar, we have used a pyrolytic stove fabricated in Morocco from locally available materials. The biochar sample collected was then crushed, sieved (<2 mm) and its physical, and chemical characteristics were analysed and compared with those of other media (soil and peat). The physical and chemical properties of the argan shells biochar revealed a highly alkaline pH, high electrical conductivity, high content of K, Na, Mg and NaNO3, low content of Ca, KH2PO4 and low content of heavy metals compared to sandy soil and peat. In addition, by increasing biochar application, the water holding capacities of biochar-sand mixtures also increased. The use of argan shells biochar to enrich the soil will be expected to improve both nutrient and water retention especially that South Western Morocco is subject to frequent drought.

Application of fractional factorial and Doehlert designs for optimizing the preparation of activated carbons from Argan shells

A high quality activated carbon has been obtained, by physical activation with steam, from a Moroccan agricultural by-product (Argan shells) and their characteristics were investigated. In order to optimize experimental conditions of the preparation, a combination of a fractional factorial design and a Doehlert design was applied. In the first step of this work, a two-level fractional factorial design 2(5–1) was used to study effects and first order interactions of various factors such as atmosphere in carbonization step, carbonization time at 400°C, activation temperature, activation time and steam flow. The results reveal that the most influential factors on the yield and the methylene blue adsorption are activation temperature, activation time, steam flow and the presence of a significant interaction between activation temperature and activation time in both cases. In the second step, activation temperature and activation time were optimized using Response Surface Methodology with a Doehlert design, and Desirability function. The optimal conditions for the preparation of activated carbon have been identified to be an activation temperature of 880°C, an activation time of 96min and steam flow fixed at this positive level of 0.2cm3min−1. The characteristics of prepared activated carbon obtained at the optimal conditions were determined using adsorption capacity of methylene blue, iodine and phenol, BET surface area, pHpzc, and surface functions based on Boehm method. Those characteristics (MB adsorption: 608.9mgg−1, iodine adsorption: 1026.4mgg−1, phenol adsorption: 633.3mgg−1, BET surface area: 1292m2g−1) were shown greater than those of a commercial activated carbon used in water treatment and those reported by other researchers studying activated carbon preparation from various solid wastes by steam activation method.On the other hand, this work showed that Argan shells are a good precursor for the production of activated carbon, by steam physical activation, with high performance to be used in water treatment applications.