Date palm fiber as a potential low-cost adsorbent for real olive oil mill wastewater treatment: kinetic, modeling, and thermodynamic study

The efficiency of the two white-rot fungi Pycnoporus coccineus and Coriolopsis polyzona in the Olive Oil Mill Wastewater (OOMW) treatment was investigated. Both fungi were active in the decolourisation and COD removal of OOMW at 50 g/L COD, but only the first fungus remains effective on the crude effluent (COD=100 g/L). Moreover P. coccineus was less affected by oxygen supplementation and exhibited a high tolerance to agitation in comparison to C. polyzona. However, it required a nitrogen supplementation to obtain faster and higher COD removal. To overcome the negative effect of agitation on fungi growth and efficiency, immobilisation of C. polyzona and P. coccineus in polyurethane foam was applied. The immobilized system showed better COD decreases during three consecutive batches without remarkable loss of performances. The results obtained in this study suggested that immobilized C. polyzona and especially immobilized P. coccineus might be applicable to a large scale for the removal colour and COD of OOMW.

Real olive oil mill wastewater treatment by photo-Fenton system using artificial ultraviolet light lamps

In recent decades, researchers have begun to investigate innovative sustainable construction materials for the development of greener and more environmentally friendly infrastructures. The main purpose of this article is to investigate the possibility of employing date palm tree waste as a natural fiber alternative for conventional steel and polypropylene fibers (PPFs) in concrete. Date palm fibers are a common agricultural waste in Middle Eastern nations, particularly Saudi Arabia. As a result, this research examined the engineering properties of high-strength concrete using date palm fibers, as well as the performance of traditional steel and PPF concrete. The concrete samples were made using 0.0%, 0.20%, 0.60%, and 1.0% by volume of date palm, steel, and polypropylene fibers. Ten concrete mixtures were made in total. Compressive strength, flexural strength, splitting tensile strength, density, ultrasonic pulse velocity (UPV), water absorption capability, and water permeability tests were performed on the fibrous-reinforced high-strength concrete. With a 1% proportion of date palm, steel, and polypropylene fibers, the splitting tensile strength improved by 17%, 43%, and 16%, respectively. By adding 1% fiber, flexural strength was increased by 60% to 85%, 67% to 165%, and 61% to 79%. In addition, date palm fibers outperformed steel and PPFs in terms of density, UPV, and water permeability. As a result, date palm fibers might potentially be employed in the present construction sector to improve the serviceability of structural elements.

The present work focuses on investigating the effect of non-fluoro short-chain alkylsilane treatment on the surface characteristic of date palm (Phoenix dactylifera) fiber. Raw date palm fiber (DPF) was treated with octylsilane and the surface properties of treated fiber was investigated using thermogravimetric analysis (TGA), fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), contact angle analysis and X-ray diffraction (XRD) on configuring the thermal stability, chemical structures and surface properties (morphology, hydrophobicity and crystallinity). The decomposition temperature of 75% mass loss raw and treated DPF, the onset of temperatures were increased from 464 to 560 °C with the introduction of alkylsilane. Hydrophobicity and crystallinity index of the DPF fibers were increased from 66.8° to 116° and 31 to 41, introducing octylsilane to raw DPF. The SEM and XRD experimental results showed that the octylsilane treatment could effectively increase the pore size and crystallinity index as an indication of the removal of non-crystalline cellulosic materials from DPFs. Thermal stability, hydrophobicity and crystallinity of the fibers increased on DFP after alkylsilane treatment. The results indicated that alkylsilane-treated DPFs were a suitable reinforcing substitute for hydrophobic polymer composite.

Environmental Context. The combination of the Fenton’s reagent with electrochemistry (the electro-Fenton process) represents an efficient method for wastewater treatment. This study describes the use of this process to clean olive oil mill wastewater, which is a real environmental problem in Mediterranean countries. Contrary to the conventional methods which reduce the pollution by removing the pollutants from the wastewater, the electro-Fenton process is shown to fully destroy (mineralize) olive oil mill wastes in water without previous extraction and without addition of chemical reagents. Abstract. Treatment of olive oil mill wastewater is one of the most important environmental problems for Mediterranean countries. This wastewater contains many organic compounds like polyphenols, which are very difficult to treat by classical techniques. An advanced electrochemical oxidation process, the electro-Fenton process, has been used as a way of removing chemical oxygen demand and colour intensity from olive oil mill wastewater. Vanillic acid, which has been selected as a model compound, and olive oil mill wastewater have been completely mineralized by the electro-Fenton process with a carbon felt cathode, using Fe2+ ions as the catalyst.

Characteristics of starch-based biodegradable composites reinforced with date palm and flax fibers

Date palm (Phoenix dactylifera) is the most significant agricultural crop, found abundantly in the Arabian Gulf in Saudi Arabia, Northern Africa, Pakistan, India, and the United States (California). Huge deposition of more than 15000 tons of date palm leaves and trunk are generated as wastes alone in Saudi Arabia. The date palm fibers from trunk and leaf possess considerable mechanical strength and modulus to many of the natural fibers and higher with respect to E-glass fibers and many aluminium alloys. Wide varieties of both thermosets and thermoplastics polymers have been modified by the reinforcement of date palm fibers derived from leaf and trunk. Date palm fibers represent a promising alternative substitute to synthetic fibers in polymer composite industries for both advanced structural and semi-structural applications. Present review article designed to be a comprehensive source of recent literature and study on date palm fibers origin, cultivation and its surface modifications. This article also intended to covers the recent findings in date palm fibers reinforced polymer composites with some interest on physical structure and chemical compositions, including their different commercial applications.

This article presents the results of a comparative experimental study on the influence of date palm fibers to replace polypropylene fibers used as reinforcement in self-compacting concrete (SCC). Indeed, the use of polypropylene fibers makes it possible to reduce the plastic shrinkage of concrete. Date palm fibers have mechanical characteristics (tensile strength and elasticity modulus) largely sufficient to replace polypropylene fibers. The use of natural fibers has several advantages, they are natural, renewable, have no affect the environment and require little energy for their transformation, unlike synthetic fibers. In this comparative study, polypropylene fiber is used as control material and date palm fiber as study material. The results obtained show that the two types of fibers decrease the fluidity and the compressive strength but increase the flexural strength and decrease the shrinkage. Date palm fibers delay the appearance of cracks more than polypropylene fibers. Date palm fibers guarantee the best results of SCCs in fresh and hardened state

A variety of natural fibers have been on research over the past years to develop alternative echo friendly materials that have comparable performance as their synthetic counter parts for use in composite materials. In this study, two different forms of date palm tree fibers were used as reinforcement materials to develop composite materials with polypropylene (PP) matrix. These two different date palm fibers are namely Date palm fiber (DPF) & Date Palm twigs (DPT). These fibers were surface modified using alkali treatment. Two different Percentages of PP (50%, 75%) were mixed with the each type of fibers to form composite pellets using double screw extruder. The mechanical properties of the different fibers reinforced composite, in treated and untreated condition were investigated. The effect of different weight fraction of Polypropylene matrix reinforced DPF or Twigs fiber composite was investigated. The results indicate that untreated DPF-PP composites possess better mechanical properties compared to all untreated & treated DPT-PP composites. Mechanical interlocking between untreated fibers and the matrix showed some increase in the mechanical properties of the untreated DPF-PP compared to the treated one. In both cases, composites having 75% PP has better mechanical properties than the 50%PP composites. This is due to the lack of compatibility between the fibers and the matrix.

Date palm (Phoenix dactylifera) fibers are considered as one of the most available natural fiber types worldwide. Large quantities of date palm biomass wastes are annually accumulated without proper utilization. These quantities are of potential interest to support the industrial sustainability by producing alternative cheap eco-friendly materials. The competitiveness of the date palm fibers in several applications particularly in automotive industrial sectors was illustrated. Date palm fiber can be considered the best regarding several evaluation criteria like specific strength to cost ratio if compared to other fiber types. The effects of using date palm fibers in natural fiber composites with different polymer matrices were demonstrated. Criteria that can affect the proper selection and evaluation of the natural fibers as well as the composites for particular applications were discussed. The benefit of natural fibers’ modifications on physical, mechanical, and other properties were also explored. Selecting the proper date palm fiber reinforcement condition can dramatically enhance its future expectations and widen its usage in different applications.

The valorization of some agri-food industry by-products, particularly plant waste, in a number of countries may be significantly interesting in the field of civil engineering because they can be used to prepare low-cost biomaterials that consume low amounts of energy and are environmentally friendly. Recently, it has been revealed that the valorization of date palm fibers (DPFs) waste and incorporating them into concrete may be one of the promising solutions that can be adopted in order to reduce or eliminate the huge amounts of this type of waste from our environment and to improve the properties of concrete. The present work aims primarily to investigate the effect of incorporating date palm waste fibers into sand concrete on the properties of this concrete in the fresh and hardened states. For this, two DPF contents were considered. First, 0.1% of DPFs with lengths 2cm and 6cm, and second 0.2%of DPFs with lengths 2cm and 6cm. Furthermore, a factorial design was used for the purpose of analyzing the influence of varying these two parameters, i.e. fiber content and fiber length, on the physico-mechanical properties of the sand concrete produced. In addition, it should be noted that the response to be considered in this design is the compressive and flexural strengths. Moreover, the JMP statistical software was utilized for analyzing the interactions observed and examining the responses that is predicted by the model generated using the factorial design. The findings showed that the expected responses obtained from the adopted model are in good agreement with the experimental data. Further, it was found that the fiber length factor has a positive effect on the response (strength). However, increasing the DPF content in the formulation of sand concrete has a negative effect on his compressive strength.

Empirical modeling of olive oil mill wastewater treatment using loofa-immobilized Phanerochaete chrysosporium

Solar driven photocatalysis using iron and chromium doped TiO2 coupled to moving bed biofilm process for olive mill wastewater treatment

In the current work, three adsorbent materials were developed: biochar derived from date palm fiber (C), date palm fiber biochar/chitosan nanoparticles (CCS), and biochar/chitosan nanoparticle composite supplemented with glutamine (CCSG). These compounds were used as solid adsorbents to remove As5+ from polluted water. Several characterization approaches were used to investigate all the synthesized solid adsorbents, including thermogravimetric analysis, N2 adsorption/desorption isotherm, scanning electron microscopy, transmission electron microscopy (TEM), attenuated total reflectance with Fourier transform infrared, and zeta potential. Date palm fiber biochar/chitosan/glutamine nanocomposite (CCSG) demonstrated good thermal stability, with a maximum specific surface area of 518.69 m2/g, a mesoporous size of 2.06nm, total pore volume of 0.25 cm3/g, TEM average particle size of 38nm, and pHPZC of 6.9. Contact time (5-60 min), pH (1-9), starting As5+ concentration (50-500mg/L), adsorbent dose (0.1-2.0 g/L), temperature (27-45 °C), and ionic strength (0.05-0.40 mol/L) were among the sorption parameters that were investigated in order to improve the adsorption conditions. It is observed that the modified samples were effectively able to remove As5+ (CCS; 256.0 and CCSG; 376.0 mg/g) than unmodified ones (C; 150.5 mg/g). The As5+ removal procedure corresponded well with Langmuir isotherm model. Thermodynamic and kinetic experiments show that the Elovich, pseudo-first order, and Van't Hoff plot with endothermic, spontaneous, and physisorption nature are the best fitted models. EDTA has the highest desorption efficiency percentage (98.8%). CCSG demonstrated enhanced reusability after six application cycles of As5+ adsorption/desorption, with only a 4% decrease in the efficiency of adsorption. This work shows that adding glutamine to the DPF biochar/chitosan composite reinforces it, resulting in the fabrication of a solid adsorbent that shows promise for use in water remediation.

The present work intends to study the treatment of olive oil mill wastewater (OMW) by natural flotation followed by anaerobic‐aerobic biodegradation, without dilution. After natural flotation, turbidity, chemical oxygen demand (COD) and polyphenol decreased by 37.7%, 3.7% and 3.3%, respectively. Whereas, anaerobic treatment removed 23.9% of nitrate, 29.1% of turbidity and 16.2% of polyphenol. However, intermittent aeration treatment showed the reduction of nitrate, turbidity and ammonium by 90%, 26.5% and 65.1%, respectively. In general, the combined natural flotation and anaerobic‐aerobic treatment of OMW, without dilution, have led to reduced turbidity, COD, polyphenol, nitrate, ammonium and phosphorus by 67.5%, 29.1%, 25.2%, 93.9%, 77.1% and 81.8%, respectively. The germination index of the treated OMW was 69% after 30% of dilution. Finally, the proposed treatment process could be used in small and medium‐sized industries as a simple, economical and effective method. Also, the produced water could be reused for irrigation.