Hazelnut Shell Research Articles

Phosphorylated hazelnut shell waste for sustainable lithium recovery application as biosorbent

Phosphorylated hazelnut shell waste for sustainable lithium recovery application as biosorbent

Prediction of chemical exergy of syngas from downdraft gasifier by means of machine learning

The rapid consumption of fossil fuels because of the increasing energy demand caused the increase in greenhouse gas emissions. However, biomass gasification is attracting much attention as an environmentally friendly and highly efficient thermochemical conversion due to its high carbon conversion and low greenhouse gas emissions. Further, downdraft gasifiers are known as the most suitable technology for biomass gasification processes because they offer an easy-to-control working environment and low investment cost. In recent years, artificial neural network models (ANN) have been used in the literature as a machine learning approach to predict gasification parameters. In this work, the parametric study was carried out for the variation of gasifier temperature (873.15 K–1173.15 K) and steam/biomass ratio (0.1–1.5) for 22 lignocellulosic biomass samples. Thus, 32,025 different experimental conditions generated by Aspen Plus® were used with Bayesian regularized ANN as a machine learning approach to predict the chemical exergy of the syngas from the downdraft gasifier. The operating parameters of gasifier temperature and steam/biomass ratio were found to be highly influential on the syngas quality and chemical exergy value of the syngas. Therefore, the operating conditions and biomass properties (carbon, hydrogen and oxygen content) were selected as input parameters for the ANN model. The regression coefficients (R2) were found to be convincingly 0.9992, 0.9991 and 0.9942 for training, test and hazelnut shell gasification data, respectively. Moreover, the results for root mean squared error (RMSE) were within satisfactory limits for the developed ANN model.

Thermokinetic analysis and product characterization of waste tire-hazelnut shell co-pyrolysis: TG-FTIR and fixed bed reactor study

The synergetic effects during co-pyrolysis of waste tires and hazelnut shell biomass were investigated concerning the product distribution and reaction kinetics. The components were blended at different ratios and investigated using a thermogravimetric analyzer coupled with a Fourier Transform Infrared spectrometer. Kinetic parameters were calculated for the blends by Distributed Activation Energy Model, Straink, and Ozawa-Flynn-Wall; activation energies varied between 100 and 300 kJ mol−1. Theoretical mass loss and activation energy results showed a synergetic interaction between components, especially for the 80% waste tire and 20% hazelnut shell biomass blends. Pyrolytic oil obtained from fixed bed experiments was analyzed by GC/MS, 1H NMR, and FTIR. Although the contents were similar, significant variations in intensities were observed. Elemental analysis showed the deoxygenation effect of co-pyrolysis with lower oxygen content and higher heating value for pyrolytic oil. The results showed that co-pyrolysis of these types of waste has the potential to be co-processed for liquid fuel production with improved properties.

Bioethanol Production via Herbaceous and Agricultural Biomass Gasification Integrated with Syngas Fermentation

In this paper, a simulation model based on the non-stoichiometric equilibrium method via ASPEN Plus was established to analyze the gasification performance of 20 herbaceous and agricultural biomasses (H&ABs) linked with syngas fermentation and product purification units for ethanol production. The established simulation model does not consider the gasification system as a black box; it focuses the important processes in gasification such as drying, pyrolysis, gasification, and connection with bioethanol production plants. The results for the 20 H&AB options suggest that the specific mass flow rate of bioethanol from 1 kg of biomass input to the unit is in the range of 99–250 g/kg, and between them, the system fed by hazelnut shell biomass remarkably outranked other alternatives by 241 g/kg production due to the high beneficial results gained from the performance analysis. Additionally, a sensitivity analysis was performed by changing operating conditions such as gasification temperature and air-to-fuel ratio. The modeling results are given and discussed. The established model could be a useful approach to evaluate the impacts of a huge numbers of biomasses and operating parameters on bioethanol output.

Co-gasification of woody biomass with organic and waste matrices in a down-draft gasifier: An experimental and modeling approach

In this paper an extensive experimental campaign about the co-gasification of virgin wood biomass with organic and waste matrices in a full-scale downdraft air gasifier is presented. In particular, wastes from cherry processing, plastic wastes, sewage sludges and hazelnut shells were co-gasified with biomass adopting different mixtures. The syngas composition was continuously measured in order to assess the gasifier behaviour and performances using these mixtures. Results obtained mixing biomass with other feedstocks up to 60% (by mass) showed that the downdraft gasifier adopted, characterized by a patented internal air distribution system, was able to maintain a good gasification performance in terms of syngas lower heating value (LHV) (>5.18 MJ/Nm3), syngas flow rate (>400 Nm3/h) and cold gas efficiency (>71.9 %).A pseudo-kinetic model of the gasifier using Aspen Plus® code was developed as well. The model, calibrated with the experimental data, proved to fit the syngas composition and physical properties with satisfying accuracy. The numerical model confirmed its usefulness in predicting the performance of the gasifier as the operating parameters vary and clearly highlighted that secondary air flow and preheating of the gasifying air are effective ways for the enhancement of the cold gasification efficiency, which can reach values around 80%.

Influence of pyrolysis temperature on bio-oil produced from hazelnut shells: Physico-chemical properties and antioxidant activity of wood vinegar and tar fraction

This study focuses on the physico-chemical properties and antioxidant activity of wood vinegar and tar fraction in bio-oil produced from hazelnut shell pyrolysis at 400–1000 °C. In all cases, temperature plays a key role in the two fraction characteristics in bio-oil; phenols are absolutely dominant compounds, accounting for over 41 wt. % in wood vinegar and above 50 wt. % in tar. The hydroxyl radical scavenging experiment revealed that the higher phenol content resulted in the stronger antioxidant activity, and tar contained more phenolic compounds, which should have shown more antioxidant activity compared with wood vinegar, but under the influence of tar complex composition and properties, the hydroxyl radical binding reactions were severely blocked, which led to less antioxidant activity, and wood vinegar showed better potential as a natural antioxidant.

PROSPECTS FOR OBTAINING A COMBUSTIBLE MIXTURE OF GASES FROM VEGETABLE AGRICULTURAL WASTE USING SOLAR ENERGY

This paper discusses the possibility of obtaining a combustible gas mixture (GHA) from a number of agricultural waste, such as stalks of cotton, grapes and tobacco, walnut and hazelnut shells, etc., by pyrolysis and gasification, using solar energy, in in particular, a solar high-temperature installation (SVTU), in which a parabolic concentrator (PC) is used to convert the sun's radiant energy into thermal energy. Provides data on solar energy resources, as well as plant waste available in various regions of Azerbaijan.

Nanocomposites of zero-valent iron@biochar derived from agricultural wastes for adsorptive removal of tetracyclines

Tetracycline antibiotics as the emerging pollutants had been drawn abroad increasing concerns. An agricultural waste, the lignocellulosic hazelnut shell, was used as the carbon source to prepare the nanocomposites of zero-valent iron@biochar by pyrolytic reduction method at 1123 K for 2 h in N2 atmosphere. The adsorptive removal of tetracycline, oxytetracycline and chlortetracycline by the zero-valent iron@biochar from aqueous solution was investigated by batch method. The optimal experimental conditions were found to be at pH 6–7 with a contact time of 40 min. The adsorbed amounts of oxytetracycline, chlortetracycline and tetracycline at 298 K were 52.7, 42.5 and 39.1 mg g−1, respectively. Adsorption process of three antibiotics by the nanocomposite pursued Langmuir and pseudo-second-order equations. Thermodynamic parameters illustrated that the adsorption was spontaneous and endothermic intrinsically. The high removal efficiencies up to 95% of the zero-valent iron@biochar for oxytetracycline and chlortetracycline from the culture wastewaters had opened the potential applications for the removal of the antibiotics.

Friction‐wear performance in environmentally friendly brake composites: A comparison of two different test methods

AbstractIn this study, an eco‐friendly brake composite sample (EFP) was produced with 3.5% hazelnut shell dust as a natural additive material. Friction tests were performed on the manufactured pad sample and on a commercial pad (CP) using both a Chase‐type test machine and a specially designed device. A different approach is presented with the evaluation of the two different test device results. The experimental results were compared using the Taguchi method and it was concluded that the braking performance of the sample with hazelnut shell dust was in accordance with international standards. As a result of the study; the nominal friction coefficient value was found to be 0.505 μ. The shearing force of the EFP and CP samples was measured at 607.3 and 850.5 N, respectively. The friction coefficient values obtained from the EFP and CP samples were in accordance with the SAE J‐661 standard and are in the “F” letter class.

Saccharification of Hazelnut and Rhododendron Biomasses Using β-xylanase from Thermotoga naphthophila

Enzymes can be used in various biotechnological applications due to the easy and cheap production. Since xylanase enzymes are preferred in various industries, researchon this enzyme is extensively being carried out. In this study, the β-xylanase gene was cloned from Thermotoga naphthophila, a thermophilic organism. The expression vector pET21a(+) was expressed in Escherichia coli BL21 (DE3). As a result of the studies, the pH, temperature and IPTG concentration of the enzyme were optimized to obtain highest expression. Dinitrosalicylic acid (DNS) was used to determine sugar content of the enzyme. The molecular mass of the purified β-xylanase enzyme was determined using sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis. The molecular mass of the enzyme was calculated to be 38 kDa. Enzymatic hydrolysis of hazelnut shell, rhododendron branch and rhododendron leaves was performed. Released reducing sugar contents from the enzymatic hydrolysis were calculated as 0.8461 mg mL-1, 0.6976 mg mL-1 and 0.3605 mg mL-1 for hazelnut shell, rhododendron branch, and rhododendron leaf respectively. In conclusion, β-xylanase enzyme can be an effective source for enzymatic hydrolysis to produce fermentable sugars from such biomasses.

Effects of natural hard shell particles on physical, chemical, mechanical and thermal properties of composites

Shelled herbal foods are widely consumed. The evaluation of the shells of these foods is important due to their features such as low cost, ease of recycling and environmental friendliness. In this study, hazelnut shell (HS), pistachio shell (PS), and apricot kernel shell (AKS) were brought to powder particles by grinding to dimensions of 300–425 µm. Some of the powder particles were converted into ash at 900°C. The amounts of cellulose, ash, humidity, and metal in these particles via chemical analyses were determined, while their structural properties via X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) analyses. Composite materials were produced by adding 15 wt.% to the polyester matrix material from these powder particles and ashes. Compression strength, hardness, specific weight, and thermal conductivity of these composites were analyzed. The lowest and highest humidity, ash, cellulose, hemicellulose, and lignin ratios in powders showed differences depending on the type of powders. The amount of Sn and K in the HS, PS, and AKS powders were close to each other, while the amount of Ca, Na, Mg, Fe, Mn, Cu, Zn and Si was higher in AKS powder. The reinforcement adding to the polyester increased the compression strength, hardness, specific weight and thermal conductivity properties.

Potential Valorization of Hazelnut Shells through Extraction, Purification and Structural Characterization of Prebiotic Compounds: A Critical Review.

Hazelnuts are one of the most widely consumed nuts, but their production creates large quantities of by-products, especially shells, that could be upcycled into much more valuable products. Recent studies have shown that hazelnut shell hemicellulose is particularly rich in compounds that are potential precursors of xylooligosaccharides and arabino-xylooligosaccharides ((A)XOS), previously defined as emerging prebiotics very beneficial for human health. The production of these compounds on an industrial scale-up could have big consequences on the functional foods market. However, to produce (A)XOS from a lignocellulosic biomass, such as hazelnut shell, is not easy. Many methods for the extraction and the purification of these prebiotics have been developed, but they all have different efficiencies and consequences, including on the chemical structure of the obtained (A)XOS. The latter, in turn, is strongly correlated to the nutritional effects they have on health, which is why the optimization of the structural characterization process is also necessary. Therefore, this review aims to summarize the progress made by research in this field, so as to contribute to the exploitation of hazelnut waste streams through a circular economy approach, increasing the value of this biomass through the production of new functional ingredients.

Combustion of hazelnut shell-lignite blends in poly-particulate beds

In this study, combustion behaviours of blends prepared from 2.18 mm mean size lignite and hazelnut shell particles in specific proportions were investigated using a vertical pre-heated furnace system through which air was flowing upwards by natural convection. The results revealed that the ignition time of the blends approached those of hazelnut shell with temperature and showed certain interactions of the two materials during the volatiles combustion period. Combustion time generally complied with volatiles and carbon combustion rates of the two materials and their blends. Carbon combustion time decreased with temperature and hazelnut ratio, and implied some interactions of the materials. Although any effect of initial furnace temperature and hazelnut ratio of the blends on the NOx emissions was not clearly seen, SO2 emission levels depended on these factors.

Effects of Oxygen and Steam Equivalence Ratios on Updraft Gasification of Biomass

Several experimental datasets available on the gasification of different lignocellulosic feedstocks were used to correlate the flow of gasifying agents with the performance of updraft gasification in an autothermic 200 kWth pilot plant. The feedstocks used included eucalyptus wood chips, torrefied eucalyptus and spruce chips, lignin rich residues from biorefined straw and reed, shells of almond and hazelnut, which were gasified in flows of air, air and steam, oxygen, oxygen and steam. Thermal profiles inside the gasifier and gas quality in terms of incondensable gas and tar content were recorded and used to calculate the energy efficiency of converting solid feedstock into gaseous and liquid carriers. Common behaviors and parametric functionalities were identified to better understand the process and the most efficient tools to achieve the desired products. In analyzing data, the ratio steam to biomass was reported in terms of the equivalence ratio, ER(H2O) i.e., the fraction of the stoichiometric quantity required to convert the feedstock into H2 and CO2. The use of steam was useful to stabilize the process and to tune the H2/CO ratio in the syngas which reached the value of 2.08 in the case of oxy-steam gasification of lignin rich residues at ER(H2O) of 0.25. Larger use of steam depressed the process by lowering the average temperature of the bed, which instead increased steadily with ER(O2). The production of tar depends on the biomass type and a substantial reduction can be achieved with the torrefaction pretreatment. The same effect was observed increasing the residence time of the syngas in the reactor, typically achieved using oxygen instead of air as main gasification flow or reducing the ER(H2O). Oxy-steam gasification of torrefied wood led to the best results in terms of cold gas efficiency and low heating value when carried out in the ranger 0.23–0.27 of both the ERs.

Oxygen and nitrogen-functionalized porous carbon particles derived from hazelnut shells for the efficient catalytic hydrogen production reaction

Due to their low cost and high availability, interest in biomass materials in catalytic studies is increasing. It is possible to increase the catalytic activities by the development of metal-free catalysts obtained by adding different atoms to carbon materials. Here, oxygen (O) and nitrogen (N) doped metal-free carbon catalysts (N-AC-N) were synthesized using activated carbon (AC) obtained from hazelnut shells by KOH activation. These metal-free catalysts were used successfully for the first time in the NaBH4 methanolysis reaction (NaBH4-MR). The structural and physical-chemical properties of the metal-free catalysts obtained were analysed by XRD (X-ray diffraction), elemental analysis (CHNS), FT-IR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), and nitrogen adsorption surface analyses. N and O doped metal-free catalyst showed very good catalytic performance against NaBH4-MR. The hydrogen production rate (HGR) with 10 mg metal-free catalyst at 30 °C and the activation energy(Ea) of the reaction were calculated as 16250 mL min−1 g−1 and 11.45 kJ mol−1, respectively. At the same time, with favourable reusability results, this metal-free catalyst is a promising candidate for the hydrogen(H2) generation system.

Adsorption of U(VI) from aqueous solution by using KMnO4-modified hazelnut shell activated carbon: characterisation and artificial neural network modelling.

This study is based on U(VI) removal from wastewater by KMnO4-modified hazelnut shell activated carbon (KM-HSAC) using adsorption technology. A characterisation study of KM-HSAC was conducted through scanning electron microscope and energy-dispersive X-ray spectroscopy (EDS) analysis. The rough surface of KM-HSAC contains many irregular microspores. The EDS pattern confirmed the U(VI) adsorption on the KM-HSAC. A batch study experiment gave optimum results for U(VI) at pH6, contact time of 160min, initial U(VI) concentration of 155.56mg/L and KM-HSAC dosage of 4g/L, with a maximum adsorption capacity of 22.27mg/g. The prediction performance of artificial neural network models was validated through the low values of statistical error (2.708 and 8.241 for RMSE of training and testing data, respectively) and the high determination coefficient value (0.987 and 0.906 for training and testing data, respectively). Experimental results suggest that KM-HSAC has a high potential for the removal of U(VI) from wastewater.

Effects of thermal aging on physical and wear properties of high density polyethylene (HDPE)/hazelnut shell (HS) polymer composites

Bu çalışmada, fındık kabuğu tozları yüksek yoğunluklu polietilen içerisine katılarak bir polimer kompoziti elde edilmiştir. Daha sonra elde edilen bu polimer kompozitine değişik ısıl yaşlandırma sürelerinde (15 ve 30 gün) yaşlandırma işlemi yapılmış ve fiziksel & mekaniksel özellikleri incelenmiştir. Fındık kabuğu tozları yüksek yoğunluklu polietilen matrisi içerisine dört farklı oranda (% 5-10-15 ve 20) katılmıştır. Yapılan testlerin sonuçlarına göre, matris içerisinde fındık kabuğu toz oranlarının artmasıyla; limit oksijen indeksi (LOI), erime akış indeksi (MFI), ısıl çarpılma sıcaklığı (HDT) ve Vicat yumuşama sıcaklığı değerlerinin düştüğü buna karşılık nem miktarı ve aşınma oranı değerlerinin yükseldiği tespit edilmiştir. Diğer yandan ısıl işlem süresinin artmasıyla da Vicat yumuşama sıcaklığı, ısıl çarpılma sıcaklığı, erime akış indeksi ve aşınma oranlarının arttığı belirlenmiştir. Buna karşılık ısıl yaşlandırma süresinin artması ile HDPE/FK kompozitinin nem emme ve limit oksijen endeksi değerleri düşmüştür.

KELAYAKAN USAHATANI TEMBAKAU VIRGINIA: STUDI KOMPARASI PADA PROSES PENGOVENAN DI KABUPATEN LOMBOK TIMUR

There are two methods of flue curing process used in virginia tobacco farmers in East Lombok, which are curing with fossil fuel and curing with local (alternative) fuels (candlenut shell, palm kernel shells, wood, and corn cobs). Now days, due to increasing fossil fuels price, farmer tend to use local fuels. The research objective was to compare the costs, income, and feasibility level of virginia tobacco farming on the use of various alternative fuels in the oven process in East Lombok Regency. The method used is descriptive survey method to 40 farmers. The cost of farming virginia tobacco using candlenut shell as fuel is Rp. 44,788,057/ha/planting season with an R/C ratio of 1.6 palm kernel shells of 45,081,109/ha/planting season with an R/C ratio of 1.5 wood of Rp. 49,498,452/ha/planting season with an R/C ratio of 1.4 and corn cobs of Rp. 39,184,196/ha/planting season with an R/C ratio of 1.8. The highest income is obtained from farmers who use corn cobs as fuel of Rp. 30,037,854/ha/planting season, the income of the farmers who use hazelnut shell and palm shell as fuel each is Rp. 25,938,788/ha/planting season and Rp. 23,757,891/ha/planting season. The lowest income using wood fuel is Rp. 16,883,748/ha/planting season. Because the R/C value is more than 1, it means that virginia tobacco farming using various alternative materials in the oven process in East Lombok Regency is feasible.

Effect of pyrolysis temperature on volatile products from hazelnut shells: products characteristics and antioxidant activity assessment of liquid products

Abstract It is being considered to pyrolyze lignin-rich biomass samples (hazelnut shells, HSs) into bio-fuels and chemicals to solve energy shortages and environmental concerns, volatile products (including liquid products and gas products) were produced and characterized from HSs pyrolysis at 400–1000 °C. With the temperature increases, the maximum output of liquid products was up to 35.79% produced at 700 °C, gas products yields increased from 21.82 to 55.46%. Gas chromatography and mass spectrometry (GC–MS) study indicated that liquid products from HSs riched in phenolic compounds, exceed 42% of liquid products and increased as the temperature rises. The application experiment showed that HSs liquid products had a significant role in antioxidant activity, and revealed that not limited to phenols, all compounds containing phenolic hydroxyl structure act as antioxidant. Composition analysis of gas products showed that more combustible gases were produced at the higher temperature, resulted in the significant increase in gas products higher heating value (HHV) from 6.21 to 24.36 MJ/kg.

Production of chitosan coated, citric acid modified almond, and hazelnut shell adsorbents for Cr(VI) removal and investigation of equilibrium, kinetics, and thermodynamics of adsorption

Removal of potentially toxic elements such as Cr(VI) from water bodies is crucial for health of aquatic organisms and human health. In order to produce an adsorbent with high Cr(VI) adsorption capacity, two different composite adsorbents were synthesized by coating citric acid modified almond and hazelnut shells with chitosan. Then, chitosan in the structure was cross-linked with glutaraldehyde. Cr(VI) adsorption performances of chitosan-citric acid modified almond shell composite (C-CA-AS) and chitosan-citric acid modified hazelnut shell composite (C-CA-HS) were investigated. The physical and chemical structures of the adsorbents before and after adsorption and chitosan coating were determined by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and energy dispersive X-ray (EDX) analyses. Optimum adsorbent dosage, Cr(VI) concentration, pH, contact time, and temperature parameters were determined by batch adsorption experiments. Accordingly, the optimum adsorbent dosages for the adsorption of Cr(VI) from the 55 mg/L Cr(VI) solution using C-CA-AS and C-CA-HS adsorbents were 1.8 g/L and 1.0 g/L, respectively. For both adsorbents, the optimum contact time is 120 min; the optimum pH is 2.0. The increase in temperature enhanced the adsorption. Langmuir, Freundlich, Scatchard, Dubinin-Radushkevich, and Temkin isotherm graphs were drawn by using equilibrium adsorption data and the adsorption parameters were calculated from these isotherms. The adsorption equilibrium was found more compatible with Langmuir isotherm. The maximum adsorption capacities calculated by Langmuir isotherm were 100.3 mg/g for C-CA-AS and 89.5 mg/g for C-CA-HS. In addition, as a result of kinetic calculations, adsorption was found to be compatible with pseudo-second-order kinetic model, and as a result of calculation of thermodynamic parameters, it was determined that adsorption was spontaneous and endothermic. The data obtained in this study showed that the recommended adsorbents have higher adsorption capacities than many adsorbents described in the literature and commercial resins. In addition, since agricultural wastes are used in the adsorbents obtained, the adsorbents are low cost.