Hazelnut Shell Research Articles

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.

Utilization of Some Plant Based Wastes for a Possible Formulation of Tea Infusion

The main objective of the current study was to investigate the potential of plant based wastes to be used as tea infusions having beneficial health effects. With this purpose, three different formulations of tomato peel, lemon peel, onion peel, tangerine peel, walnut and hazelnut shell, oleaster, olive leaves, cypress cone and hawthorn were developed and these tea blends were evaluated in terms of total phenolics, radical scavenging activity, color and sensory properties. Final beverages contained considerable phenolic contents and showed significant antioxidant activity. The infusion of onion peel, lemon peel, walnut shell and cypress cone blend contained the highest amount of total phenolics (160.2 mg GAE/L). However, tomato peel, hawthorn, olive leaf and cypress cone blend showed good DPPH radical scavenging activity (79.65%) and appreciated with higher scores by sensory analysis.

Challenges of dry hazelnut shell surface for radio frequency pasteurization of inshell hazelnuts

Thermal inactivation kinetics (D and z values) of Salmonella and Enterococcus faecium in fresh hazelnut shell and kernel were determined. Aluminum pouches containing either 1.5 g hazelnut shell powder or 2 g of ground kernel inoculated with either bacterium at their original water activities (aw-shell = 0.91 ± 0.01, aw-kernel = 0.93 ± 0.01) were isothermally treated in a thermal death time (TDT) sandwich at 55, 60, 65, 70 and 75 °C for determining D values. A single layer inshell hazelnuts with one inoculated nut located at the center (cold spot) of a tray was subjected to hot air assisted radio frequency (HARF) heating in a 6-kW 27.12-MHz RF system with hot air temperature at ~75 °C for 10, 15 and 20 min. The log-linear model fits survival data of both Salmonella and E. faecium in hazelnut shell and kernel well. The D-values of both bacteria in hazelnut kernel were higher than those in hazelnut shell. Higher D-values of E. faecium demonstrated that it is a suitable surrogate for Salmonella in both hazelnut shell and kernel. There was a large variation between calculated (based on F-value) and experimental log reductions of Salmonella. Only 1.0 ± 0.1 log reduction of Salmonella was achieved in inshell hazelnut after 20 min of HARF heating. Because the RF pasteurization is a simultaneous drying process, the F-value methodology could not give an accurate and reliable lethality prediction due to the increased thermal resistance of Salmonella caused by moisture loss. Around one log increase in Salmonella inactivation was achieved after spraying 0.1% buffered peptone water (BPW) on inshell hazelnuts for the same RF treatment condition. While the water activity of the ground shell was 0.91 ± 0.01, the water activity of top surface layer of the shell where bacteria were inoculated for the RF treatment was 0.17 ± 0.01 before RF treatment. This very dry shell surface was the major factor for the deviation of calculated F-value from the observed microbial reduction in this RF microbial study. The dry shell surface creates a challenge for thermal inactivation of pathogens on inshell hazelnuts and other nuts with a similar shell structure. An efficient pasteurization protocol for inshell hazelnuts needs to be developed and optimized by combining surface disinfectants/salt solution and RF process conditions to enhance microbial food safety and quality of hazelnuts. This study provides valuable information and direction to the hazelnut industry for improving safety and quality of hazelnuts.

Screening of New bio-based materials for radioactive iodide adsorption from water environment

Several bio-based adsorbents containing cations were screened for radioactive iodide removal from a water environment. The efficiency of the selected adsorbents was assessed in different pH, temperature as well as competitive ions. Based on the adsorption capacity, iron-alginate (Fe-Alg), hazelnut shells, and sacha inchi shells were selected as potential adsorbents. They possessed 139, 18.9, and 45.1 mg/g iodide (I−) adsorption capacities, respectively. The adsorption equilibrium time for Fe-Alg was 30 min, while hazelnut shells and sash inchi shells took 120 min to stabilize. The adsorption results fit the Langmuir isotherm model with predicted adsorption capacities similar to those of the experimental data. The fitting of pseudo-first-order reaction and the negative values of the Arrhenius activation energy inferred that the adsorption had a physical nature. The iodine X-ray absorption edges of 4552.83–4553.40 eV from the near-edge structure analysis confirmed the physisorption, as the I− in bio-based adsorbents did not go through any chemical transformation. Fe3+ was used to synthesize Fe-Alg. With an energy dispersive X-ray analysis, magnesium, potassium, and calcium were detected in the hazelnut shells and sacha inchi shells. Consequently, the binding of I− to the surface of the adsorbents was mainly through electrostatic forces, with the cationic species on the surface of the adsorbents. The selected bio-based adsorbents could be used for industrial effluents in natural water environments as they exhibited I− adsorption at various pH levels, temperatures, and in the presence of competitive anions.

Nutshells as Efficient Biosorbents to Remove Cadmium, Lead, and Mercury from Contaminated Solutions.

The release of potentially toxic elements into the environment, and their effects on aquatic ecosystems still present a real threat. To avoid such contamination, the use of biological sorbents as an alternative to conventional and expensive water remediation techniques has been proposed. The present study evaluated the potential of 0.5 g L−1 of peanut, hazelnut, pistachio, walnut, and almond shells to remove the requisite concentrations of cadmium (Cd), lead (Pb), and mercury (Hg) from contaminated water. Hazelnut shells were identified as the sorbent with the highest potential and were evaluated in mono- and multi-contaminated mineral water. The influence of sorbent-intrinsic and solution-intrinsic characteristics were assessed. Differences among sorbents were attributed to varying percentages of their main components: cellulose, hemicellulose, and lignin. Matrix complexity increase caused a decrease in Cd removal, presumably due to the diminution in electrostatic interaction, and complexation with anions such as Cl−. When simultaneously present in the solution, contaminants competed, with Pb showing higher affinity to the sorbent than Hg. High efficiencies (>90%) obtained for hazelnut shells for all elements in ultrapure water and for Pb and Hg in mineral water) reveals the high potential of this low-cost and abundant waste for use in the remediation of contaminated waters (circular economy).

Tuning the linear and nonlinear optical absorption properties of ZnS/hydrochar nanocomposites by concentration of nanoparticles

Abstract In this article, the effects of nanoparticles aggregates and concentration on linear and nonlinear optical absorption properties of ZnS and ZnS/carbon-based materials in polymethyl methacrylate (PMMA) matrix have been investigated. Carbon-based materials were synthesized via the hydrothermal carbonization method. Hazelnut shell was preferred as a feedstock of carbon material due to its high production capacity in Turkey. Thin films consisting of 10, 20, and 30 wt % nanoparticles were obtained to discover the effect of weight concentration on optical properties. The linear and nonlinear absorption properties were characterized by UV–Vis spectroscopy technique and open aperture Z-scan measurements with 4 ns pulses at 532 nm. A theoretical model containing one photon, two photon and free carrier absorption and their saturations were used for the fitting of the experimental data. The band gap decreased with the increasing of the weight concentration of nanoparticles in PMMA. Z-scan experiment results showed that the highest effective nonlinear absorption coefficient was obtained for the thin films with 30 wt% nanoparticle concentration which had also the smallest bandgap energy. The effect of nanoparticles aggregates on the band gap energy and nonlinear absorption was also observed. The transmission electron microscopy (TEM) results indicated that the addition of carbon caused the aggregation.

Biochemical characterization and stability of Bacillus subtilis polygalacturonase produced using hazelnut shells by submerged fermentation

Biochemical and bio-catalytic properties of an enzyme are essential to evaluate its potential industrial applications in food, pharmaceutical, textile, paper and pulp. More specifically, identifying optimal pH and temperature, and their effects on the residual enzyme activity are of high priority in biochemical characterisation. Therefore, in this study, polygalacturonase (PGase) produced as an extracellular enzyme in an earlier study growing Bacillus subtilis on hazelnut shell hydrolysate was evaluated under varying pH and temperature for its stability. The optimal pH and temperature values of the enzyme were found as 7.0, and 50 °C, respectively. The enzyme Km and Vmax values were identified as 0.52 mg/mL and 3.27 μmol/min. The enzyme retained about 93 and 78% of its initial activity at 50 and 60 °C after 7 h, respectively. SDS-PAGE revealed a single activity band with molecular weight of 50 kDa. The half-life of PGase at 50 and 60 °C were 57.8 and 23 h, respectively. Thus, the results prove the potential of the B. subtilis pectinase produced using hazelnut shells in food processing e.g. extraction and clarification processes or treatment of pectic waste water.

Processing of hazelnut (Corylus avellana L.) shell autohydrolysis liquor for production of low molecular weight xylooligosaccharides by Aureobasidium pullulans NRRL Y–2311–1 xylanase

In this study, a versatile process for the production of xylooligosaccharides (XOS) with a low degree of polymerization (DP 2–6) from hazelnut shells was designed. This process included autohydrolysis integrated with sequential enzymatic hydrolysis by crude xylanase produced with Aureobasidium pullulans NRRL Y–2311–1 from wheat bran. Autohydrolysis of hazelnut shells was carried out at a solid:liquid ratio of 1:6 (w/w) and 190 °C non-isothermally. The effects of several parameters on enzymatic hydrolysis of the autohydrolysis liquor were determined. The maximum XOS (DP 2–6) production was 22.5 g/L which was obtained at pH 5.0 and 40 °C using enzyme concentration of 240 U/g XOS and substrate concentration of 72 g/L. Under these conditions, 31.29 % of the substrate (total XOS) was converted to low-DP-XOS; xylobiose and xylotriose are being the major oligomers. This is the first study on the application of A. pullulans xylanase in production of xylooligomers from hazelnut shells.

Opportunities for the use of hazelnut shell as a lightweight aggregate in the production of concrete

Today, the increase in heating and energy costs has increased the importance of insulation in buildings and new searches are being made for this purpose. As a result of these searches, studies on the production of lightweight concrete have come to the forefront, to improve the insulation properties of concrete. In this study, the usability of hazelnut shells, one of the important agricultural products of Turkey, which are post-harvest waste materials as a lightweight aggregate in concrete, was investigated. To this end, concrete was produced by replacing the aggregate with hazelnut shell by 3%, 6%, 9%, 12% and 15%, and the physical, mechanical and thermal properties of this concrete, were examined. As a result of the study, it was determined that hazelnut shell, which is an agricultural waste, could be used as aggregate in the production of concrete and that lightweight concrete with sufficient strength and durability and improved heat and sound insulation could be produced, provided that the amount of hazelnut shell to be added to the mixture would not be more than 10% of the aggregate.

Investigation of hazelnut shells driven hard carbons as anode for sodium-ion batteries produced by hydrothermal carbonization method.

To be used as Na-ion battery anodes, hard carbon electrodes are synthesized from biomass, explicitly hazelnut shell (HS): via hydrothermal carbonization (HTC) followed by further pyrolysis at different temperatures (500, 750, 1000 °C). Then, the resulting hazelnut shell-based hard carbons are investigated using various methods including Fourier-transform infrared spectroscopy, scanning electron microscope, X-ray diffraction, galvanostatic charge/discharge, and electrochemical impedance spectroscopy. The effects of binders (PVdF, Na-alginate, CMC, and PAA) on electrochemical performance are determined. The obtained composite electrodes with different binders are tested in sodium half-cell configurations. A strong correlation is recognized between carbonization temperature and electrochemical performances and structural characteristics. The better cycling performance is accomplished with the electrode carbonized at 1000 °C with Na-alginate binder. After 100 cycles, specific capacity of 232 mAh × g-1 at 0.1C current density is achieved. This work represents an economical and feasible process to convert hazelnut shells into hard carbon.

Effects of Chemical Composition and Pyrolysis Process Variables on Biochar Yields: Correlation and Principal Component Analysis

Abstract Based on a systematic review, 19 case studies were selected, focusing on the production of biochar through pyrolysis of five lignocellulosic biomasses (olive husk, beech wood, corncob, spruce wood, and hazelnut shell), under constant pressure (0.1 MPa) and temperature from 650.2 to 973.0 K. Interactions between process variables (temperature, residence time of the vapor phase and heating rate), biomass chemical composition variables (lignin, holocellulose, ash, carbon, nitrogen, oxygen and hydrogen content) and biochar yield-CY were evaluated by Pearson’s correlation matrix and Principal Component Analysis-PCA. Strong correlations (|r| ≥0.75, p<0.05) were found for lignin and CY (0.78); carbon and CY (0.76); nitrogen and CY (0.77). Three variables of biomass chemical composition were the most important ones for the first principal component-PC1; process variables (heating rate and the vapour residence time) were the most important ones for the second principal component-PC2. Experiments with hazelnut shell as feedstock were associated with higher CY.

Optimizacija metanolize korišćenog suncokretovog ulja katalizovane pepelom ljuske lešnika

The methanolysis of used sunflower oil catalyzed by hazelnut shell ash was studied to evaluate the statistical significance of the process factors, i.e., the initial methanol-to-oil molar ratio, the catalyst amount, and the reaction time on fatty acid methyl ester (FAME) content and to determine their optimal values ensuring the highest FAME content. The reaction was conducted in a batch reactor at the methanol-to-oil molar ratios of 6:1-18:1, the catalyst amounts of 1-5% (of the oil weight), and the reaction time of 10-50 min. Furthermore, statistical modeling and optimization were performed using a modified second-order polynomial model developed by the response surface methodology in combination with a 33 factorial design with three central points. The analysis of variance showed that all three factors, the two-parameter interaction of the catalyst amount and the reaction time, as well as the quadratic term of the reaction time, had a statistically significant effect on FAME content. The optimum conditions were found to be the methanol-to-oil molar ratio of 10.34:1, the catalyst amount of 5%, and the reaction time of 34 min. The predicted value of FAME content was 99.63%, which agreed well with the experimentally determined FAME content (97.15%).

Highly Efficient Nitrogen-Doped Porous Carbonaceous CO2 Adsorbents Derived from Biomass

In this manuscript, N-doped porous carbonaceous CO2 sorbents were synthesized using biomass waste hazelnut shell as the raw materials, melamine as the nitridation agent, and KOH as the porogen. The...

Biofuel characteristics and combustion emissions of poultry litter and lignocellulosic biomass

AbstractBroiler chicken industry generate different kinds of organic wastes mainly poultry litters (PL), which presenting high energy potential, but significant incineration burdens due to the mineral compositions. In the present study, the combustion potential of PL and locally available biomass co‐combustion candidates were evaluated based on proximate, ultimate, ash constitute, and exhaust gas emission. High heating values measured for PL samples were in the range of 13.5–14.6 MJ/kg and low heating values were 12.9–13.6 MJ/kg, respectively. The ultimate analysis result of PL was as follows; C (46.5 ± 1.3%), O (44.8 ± 0.7%), H (3.6 ± 0.3%), N (3.9 ± 0.3%), and S (0.9 ± 0.1%). Ash deposit challenging minerals were abundant in PL, in contrasting to the lignocellulosic biomass; wood residue (WR), hazelnut shell (HS), corn stalk (CS), and giant reed (GR), which can serve mitigation potential. High nitrogen and sulfur concentrations in PL had significantly increased the NOx and SO2 emissions but confirming related standards. Despite the high exhaust gas and ash emissions, the energy recovery practices of PL co‐combustion with lignocellulosic biomas allow environmentally safe management option for PL.

ANALISA SIFAT FISIK DAN KIMIA BRIKET ARANG DARI CAMPURAN TANDAN KOSONG AREN (Arenga pinnata Merr) DAN CANGKANG KEMIRI (Aleurites trisperma)

The waste of candlenut shells and empty sugar palm bunches has considerable potential and can be used as raw material for charcoal briquettes. This study aims to analyze the properties of charcoal from a mixture of candlenut shells and palm sugar bunches on the physical properties of the charcoal briquettes produced. To determine the effect of the mixture of candlenut charcoal shells and sugar palm empty fruit bunches, treatment of 100% candlenut shells, 100% sugar palm empty bunches, 75% candlenut shells + 25% sugar palm empty bunches, 75% empty sugar palm bunches + 25% candlenut shells, 50% candlenut shell + 50% sugar palm bunches, the adhesive used is tapioca flour. Charcoal briquettes produced by the water content ranged from 7.568% - 11.734%, density 0.520g / cm³ - 0.604g / cm abu, the average ash content ranged from 15% - 22.666%, flying substance content 43.666% - 52%, bound carbon ranged from 17,335% - 44,098%, and calorific value 3676,86kal / g - 4749,606kal / g. The water content that meets ASTM is found in treatment A (100% hazelnut shell) of 7.568%, other treatments do not meet ASTM standards. Density, ash content, fly substance content, bound carbon and calorific value produced from various treatments none meet the standard.Keywords: Aren empty bunches charcoal briquettes; candlenut shell briquettes; influence of physical and chemical properties; ASTM standards

Investigation of the Thermal and Mechanical Properties of Organic Waste Reinforced Polyester Composites

The aim of the research is to investigate the usability of composites produced using the organic waste from hazelnut and corn processing in the Black Sea Region in constructional applications with regard to mechanical and thermal conduction. Polymer composite test samples were produced to which hazelnut shells, corn stalk, nettle stalk (excl. fibres) and nettle fibres had been added in varying (5, 10, 15, 20%) weights to the polyester matrix. Thermal conductivity coefficients were determined in the context of the thermal properties of composite samples. In addition, mechanical properties were determined by compression strength and a three-point bending test. The physical properties of the wastes were determined via XRD, glass transition temperature, one of the thermal features of the composites that is found via DSC and, lastly, the thermal conductivity and specific heat capacity are determined via a heat flow meter. The effect of organic waste amounts and their chemical and physical features on composites’ mechanical and thermal properties are discussed in this study. The results of the study show that nettle stalk-reinforced composites have a low density and more advantageous features than the other composites tested in terms of their thermal conductivities.

NANOFIBER PRODUCTION FROM LIQUEFIED HAZELNUT SHELL WITH THE ADDITION OF REDUCED GRAPHENE OXIDE AND POLYVINYL PYRROLIDONE

In this study, in order to produce nanofibers from waste hazelnut shells, a lignocellulosic biomass, firstly, liquefied hazelnut shell (LHS) was obtained by liquefaction of waste hazelnut shells using phenol and some chemicals. Then, reduced graphene oxide (RGO) was produced by Hummers’ method. RGO and polyvinyl pyrrolidone (PVP) were added to LHS, in certain proportions, to form seven different LHS-RGO-PVP solutions with ethanol/dimethylformamide (EtOH/DMF). From these solutions, nanofiber surfaces were obtained by a semi-industrial electrospinning device. The morphology of the nanofibers and the properties of the electrospinning solution were investigated, and it was observed that the optimum nanofibers were obtained from 7.5% LHS/10% PVP/5.6% RGO solution by the electrospinning method. It has been determined that the conductivity is slightly reduced by the addition of RGO to the solution, the viscosity is greatly reduced, the nanofiber diameters are reduced by approximately half, and thinner nanofibers are obtained

Hierarchically structured two-dimensional magnetic microporous biochar derived from hazelnut shell toward effective removal of p-arsanilic acid

Hierarchically structured two-dimensional magnetic microporous biochar (MMBC) derived from a biomass hazelnut shell was prepared and employed for effective adsorption of a typical organoarsenic compound p-arsanilic acid (p-ASA). By a simultaneous ZnCl2 activation and FeCl3 graphitization method, the as-fabricated MMBC possessed a hierarchical structure composed by two-dimensional graphene oxide-like flakes, a high specific surface area of 1172.7 m2 g−1 and good ferromagnetic behavior. Adsorption batch experiments revealed that the MMBC had a higher adsorption capacity of 218.2 mg g−1 and removal efficiency of 87.3% toward the p-ASA than those of the pristine biochar (BC) and the microporous biochar without FeCl3 graphitization (MBC). The adsorption kinetics dates were fitted well by the pseudo-second-order adsorption model, and the adsorption isotherms conformed well to both Langmuir and Freundlich model. Due to the rich oxygen-containing functional groups (C-O, C = O, Fe-O, Zn-O) and the complex Fe-based components, the adsorption mechanism is proposed to involve synergism between pore adsorption, electrostatic interactions, π-π interactions, hydrogen bonding and coordination interactions. Considering the easy access to biomass and high adsorption capacity to p-ASA, the current MMBC would have good potential applications for controlling the risk of organoarsenic compounds such as p-ASA in aquatic environment.

Effect of sequential pretreatment combinations on the composition and enzymatic hydrolysis of hazelnut shells

Hazelnut shells, a high lignin containing biomass, were subjected to individual and sequential liquid hot water (LHW), alkaline (AP) and dilute acid pretreatments (DAP). Among the single pretreatments, LHW demonstrated the highest cellulose recovery of 98.1%, DAP resulted in the highest hemicellulose solubilization of 56.0%, and AP of the highest lignin removal of 49.6%. Employing two-step pretreatment on hazelnut shells, in general, demonstrated an enhanced action of the second pretreatment; therefore, the sequence of the pretreatment methods had a significant impact on both substrate characteristics and enzymatic hydrolysis efficiency of biomass. In terms of delignification, AP-LHW achieved 60.7% lignin removal, while LHW-DAP showed the highest hemicellulose removal of 93.8% and DAP-LHW resulted in the highest cellulose recovery of 94.0%. Structural properties of raw and pretreated hazelnut shells were observed by FTIR. The maximum glucose recovery of 54.9% was observed in DAP-LHW pretreated samples. For this pretreatment combination, almost 1.8 MJ total energy was required to recover 10.2 g glucose. The findings indicated that complete removal of the physical barrier of lignin and hemicellulose might not be essential; partial relocation of lignin and alteration of cellulose structure may also be efficient in increasing the sugar recovery from the lignocellulosic biomass.

Preparation of Porous Biochars by the Co-Pyrolysis of Municipal Sewage Sludge and Hazelnut Shells and the Mechanism of the Nano-Zinc Oxide Composite and Cu(II) Adsorption Kinetics

Municipal sewage sludge (MSS) and hazelnut shells were selected for co-pyrolysis and chemically activated with K2CO3 in a N2 atmosphere. The biochar was then modified by photocatalysis. Hazelnut shells, as a solid waste, were selected as a carbon source additive because of its high cellulose content and similar structure to natural wood. Using hazelnut shells could increase the specific surface area, enhance the porosity, and improve the adsorption capacity of the biochar. Hazelnut shells could also reduce the content of heavy metals in the raw biochar materials, along with increasing the ecological security of biochar and contributing to its further development and utilization. FTIR was used to study the changes in the functional groups on the biochar surface. The layered porous structure of the biochar was observed by SEM. The Cu(II) adsorption capacity of the biochar was 42.28 mg/g after 24 h. The Langmuir and pseudo-second-order models effectively described Cu(II) adsorption.