Apricot Kernel Shell Research Articles

Development of a Production Process for Biomass-Based Activated Carbon via Hydrothermal Carbonization Method

This study presents a process development including detailed characterization of hydrochars and activated carbons produced by hydrothermal carbonization and chemical activation methods using apricot kernel shells (AKS). Initially, the AKS were processed by grinding, followed by subjecting them to hydrothermal carbonization at 240ºC for 24, 36, and 48 hours, resulting in three distinct hydrochars. Subsequently, these hydrochars were mixed with KOH for 3 hours and subjected to a carbonization process at 700°C for 1 hour to obtain activated carbons. Various characterization methods such as Brunauer-Emmett-Teller (BET) surface area analysis, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS), X-Ray Diffraction (XRD) analysis, and Fourier-Transform Infrared spectroscopy (FTIR) measurements were employed to determine the properties of the activated carbons. The results obtained indicate that the duration of the hydrothermal reaction increases the carbon content and leads to the formation of porous structures. Particularly, the chemical activation process was found to be effective in pore formation, as evident in SEM images. In conclusion, this study provides a detailed description of the characteristic properties of hydrochars, and activated carbons derived from AKS.

Catalytic pyrolysis of apricot kernel shell over metal supported MCM-41 catalysts obtained by synthesizing sonochemical method

In this study, it is targeted to examine the efficiency of metal supported MCM-41 catalysts on the liquid product yield from pyrolysis process of apricot kernel shell selected as a biomass and to characterize the pyrolysis liquids. In the non-catalytic pyrolysis experiments, the maximum liquid yield is obtained as 21.41 % at 500 °C. At the determined optimum condition, catalytic pyrolysis process of the biomass sample is performed with metal supported MCM-41 catalysts synthesized by sonochemical method (metal: aluminium, cobalt, iron) at different ratios to biomass (1 and 2 wt %). The pyrolysis procedures of apricot kernel shell are carried out in a tubular fixed-bed reactor at different pyrolysis temperatures. The use of catalysts improved both the liquid product (tar) yield and tar quality in respect to the calorific value, the distribution of hydrocarbons and the elimination of oxygenated groups. The results revealed that all metal-supported MCM-41 catalysts, especially the Fe-MCM-41 catalyst ratio of 2, showed an excellent catalytic ability for thermal conversion of biomass. In the catalytic pyrolysis experiments carried out at 500 °C, 75.84 % conversion to liquid and gaseous products was obtained using 2 % Fe-MCM-41 catalyst, and the calorific value of the liquid product obtained was determined as 40.96 MJ/kg. The functional group analyses in the structure of the liquid products are characterized using FT-IR spectroscopy, and the distributions of the aliphatic/aromatic fractions of the liquid products are characterized using GC-MS technique. The H/C ratio of the liquid product obtained from catalytic pyrolysis is between light and heavy petroleum products and also has lower oxygen content and higher calorific value, indicating the potential of metal-supported MCM-41 catalyst for renewable hydrocarbon production from apricot kernel shell.

SOFT MODIFICATION AND FUNCTIONALIZATION OF LIGNOCELLULOSIC BIOMASS USED AS A LOW-COST EFFICIENT BIOSORBENT TO REMOVE BASIC FUCHSINE FROM AQUEOUS SOLUTION

This study proposes a new modification of lignocellulosic biomass based on apricot kernel shells with composite activation KI/KOH and functionalized with a tolerant material (MgO) powder. Apricot kernel shells (NAK), modified apricot kernel shells (MAK) and doped apricot kernel shells (DAK) obtained were characterized using various methods, such as infrared spectroscopy (FTIR), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and point of zero charge (pHpzc). The adsorbents were also evaluated in batch adsorption, using basic fuchsine dye (BF) to determine the performance and specific capacity of the adsorption process. The results showed that only 90 min and 0.1 g of DAK or MAK are sufficient to remove 93% and 91%, respectively, of basic fuchsine from aqueous solutions with a concentration of 20 mg/L in a volume of 100 mL. The MAK and DAK adsorbents can be reused for 5 cycles before their yield decreases below 50%, without requiring complex regeneration procedures, only drying for 4 h at 105°C. The evolution of adsorption was analyzed under different parameters, such as contact time, initial dose of adsorbent, initial dye concentration, initial pH, and temperature. The kinetic adsorption models indicate that the pseudo-second-order model was more suitable than the pseudo-first-order and intraparticle diffusion models for describing the adsorption process. The equilibrium adsorption data of BF were better fitted by the Langmuir isotherm, compared to the Freundlich and Temkin isotherms.

The effects of using apricot kernel shell, an environmentally friendly material, in composite brake pads on friction performance

Research shows that there is an increasing interest in alternative friction materials that do not harm human health and the environment, especially after the harmful effects of asbestos were revealed and its use was banned. This study evaluates the potential of apricot kernel shell, an agricultural waste, to be used as a bio-material in brake pad compositions. Composites containing different granule sizes and amounts of apricot kernel shell were experimentally tested for friction performance using a dynamometer. The addition of apricot kernel shell to the brake pad compositions slightly increased the noise level but improved the coefficient of friction. These findings reveal the potential of using apricot kernel shells as an economical and environmentally friendly material in brake pad compositions.

Implementation of Taguchi method, ANOVA and regression analyses to enhance char yield by carbonization in lignite-biomass blended

ABSTRACT Energy is a basic need for modern societies. Renewable energy refers to producing and using energy without harming the environment and without consuming resources. The transition to renewable and sustainable energy can provide many environmental, economic and social benefits. Academic research plays an important role in achieving this transition. Sustainable energy is critical to protecting the environment, promoting economic development and supporting social improvements. The transition to sustainable energy is a necessity for the future of humanity. For this purpose, in this study, lignite and biomass (apricot kernel shell) carbonization experiments were carried out under different conditions. Mixing ratio (Lignite/Biomass (w/w 1:1, 1:2, 1:3)), temperature (400°C, 500°C, 600°C) and heating rate (10°C/min, 30°C/min, 50°C/min) were determined as variable parameters. Taguchi’s experimental design was used to optimize the parameters. The orthogonal array design plan was determined as L9 according to the available variables (33 x 33). Since the study aimed to obtain clean solid fuel, char yields were taken into account from the results. Signal-to-noise (S/N) ratios were calculated based on the larger the better condition. As a result of the carbonization experiments performed under Taguchi optimization conditions, it was determined that the S/N ratio was 31.73 and the char yield was 40.19%. Since the estimated char yield with the Taguchi method was 38.85%, it was concluded that the optimization was achieved with 96.67% accuracy. The test parameters satisfying these conditions were determined as 1:1 lignite/biomass mixing ratio, 400°C temperature and 30°C/min heating rate. As a result of the ANOVA analysis, it was seen that the heating rate did not have a significant effect on these parameters. In contrast, the temperature and mixing ratio were important variables. Also, regression analysis (linear and quadratic) was used in this study to calculate the equations for the prediction of char yield. It was concluded that the linear regression model was more successful in estimating the char yield.

INFLUENCE OF HEATING CONDITIONS ON TEXTURE PARAMETERS AND ADSORPTION PROPERTIES OF APRICOT KERN SHELL CARBONIZATES

Some results of a comparative analysis of the textural parameters and sorption characteristics of carbonizates obtained by microwave and traditional heating of apricot kernel shells are presented. It has been shown that sorbent samples obtained by microwave carbonization of shells, in comparison with sorbents obtained by traditional heating, are characterized by a more uniform distribution of pore sizes, greater adsorption capacity and low fractal dimension of the surface.

Low tar yield and high energy conversion efficiency in a continuous pyrolysis reactor with modified ribbon screw conveyor

The high temperature batch and continuous pyrolysis of rice husk, sewage sludge, composite waste, hazelnut and apricot kernel shell were performed at 850 °C in a rotating batch reactor and a continuous reactor with a modified ribbon screw conveyor. Batch results were used in the continuous reactor design and comparison. At the continuous pyrolysis experiments, mixing and conveying efficiency of screw and thermal cracking performance of reactor, heated gas line and cyclone were investigated. Each material was fed into the reactor continuously with a feed rate of 4.5 kg/h for 3.5 h, and then the pipelines and reactor were monitored and collected tar and char were analyzed. The mixing unit and uninterrupted heated system showed excellent performance on tar reduction and tar yields were lower than 1.7 % for all materials. Separation of char dust from the gas without tar condensation in a heated cyclone prevented blocking in gas lines. With the secondary reactions syngas energy conversion efficiency for rice husk, sewage sludge, composite waste, hazelnut shell, and apricot kernel shell were 67.76 %, 59.22 %, 76.35 %, 56.96 %, 61.98 % respectively. With the new design with a modified ribbon screw, different types of materials were decomposed with minimum char yield in less than 15 min without mechanical problems. The high capacity of the installed reactor as 1–10 kg/h moved the technology readiness level (TRL) to 5 and set an example for demonstration in operational environment.

Preparation of apricot kernel shell powder added polyester/calcium carbonate composite discs and investigation of their abrasive properties

Apricot kernel shell is suitable filler for abrasive materials with its strong, hard structure and dense cellulose content. Therefore, within the scope of this study, polyester composite (PE-CAC) discs containing apricot kernel shell powder were prepared in order to prepare abrasive polyester composite discs. In order to prevent these discs from damaging the surface on which they are applied during use, different amounts of calcium carbonate were added into the structure. The chemical structure of the obtained composite discs was confirmed by Fourier transform infrared spectroscopy. Surface morphology and structure were confirmed by scanning electron microscopy technique. The distribution of additives within the composite structures was examined by EDX spectroscopy. The effect of heat generated during the etching process on the composite disc structure was investigated using thermal analysis techniques. The added composite structures were transformed into cylindrical discs with a diameter of 45 mm and a height of 30 mm and were used to remove paint on metallic surfaces. As the amount of apricot kernel shell powder in the composite structure increases, the abrasion efficiency increases. Additionally, as the PE/CaCO3 composite disc application time increased, a significant decrease in surface roughness was observed. Ideal surface roughness was achieved, especially after 10 seconds of application time. As a result, PE/CaCO3 composite discs with apricot kernel additives present an important alternative to existing methods, especially in the cleaning of dirt, rust and paint on metallic surfaces.

Thermal energy storage performance evaluation of bio-based phase change material/apricot kernel shell derived activated carbon in lightweight mortar

The synergy between phase change materials (PCMs) and activated carbon (AC) obtained from biomass is an energy-efficient method for creating composite materials with enhanced thermal performance. This study presents such a leak-proof composite with enhanced properties through the impregnation of bio-based lauric acid (L)-capric acid (C) eutectic mixture (LCEM) as a PCM in the AC derived from apricot kernel shells (AC-AKS) framework. The manufactured AC-AKS/PCM composite was subsequently incorporated into cement-pumice based mortar (CPM) in various proportions. This was done to produce energy-efficient construction materials aimed at increasing the thermal performance of buildings. Morphological, physical, thermal stability, mechanical strength, thermal energy storage (TES) and solar thermoregulation performances of the obtained leak-proof composite PCM were experimentally determined. The compressive strength of CPM samples with TES ability (TESCPM) was found 6.8 MPa, 4.3 MPa and 2.1 MPa for TESCPM1, TESCPM2 and TESCPM3, respectively. The relatively lower mechanical strength values can be accepted when considering their thermal regulation performances. The apparent porosity was around 26 %, while water adsorption around 24 % for TESCPM3. FTIR results proved the presence of well chemical compatibility between AC-AKS and PCM. The DSC results exposed that the AC-AKS/PCM composite had a melting temperature and a latent heat capacity of 21.58 °C and 126.8 J/g, respectively, while these values were within the range of 18.93–20.51 °C and 10.55–30.32 J/g for the TESCPMs. TGA results exposed that the functioning temperature of the AC-AKS/PCM was greatly lower than the limit temperature value measured for its thermal degradation. The solar thermoregulation performance test indicated that the fabricated TESCPM exhibited noteworthy advantages by providing the cooling effect throughout the daytime as well as the heating effect throughout the nighttime. All of these favorable properties make the proposed AC-AKS/PCM-integrated CPM promising materials for innovative TES applications in construction elements.

The effects of apricot kernel shell nanobiochar on mechanical properties of cement composites

Valorization of agricultural wastes is important both economically and environmentally. This study aimed to investigate the use of biochar as a filler to improve the mechanical properties of mortar and to help sequestrate CO2. The biochar was produced by pyrolysis of apricot kernel shell at 500 °C. Nanobiochar particles with dimensions less than 500 nm were obtained by high-energy ball milling process. Scanning electron microscope was used for determining the morphology of nanobiochar. The nanobiochar at different volume percentages [0.00-0.04-0.06-0.08-0.12-0.15%] was added to mortar. The mortar was casted into 40x40x160 mm molds. After water curing at 20°C for 28 days, compressive strength and flexural strength tests were performed. The mixture containing 0.04% nanobiochar by volume had an increase in flexural and compressive strengths by 5% and 15% respectively, while its fracture energies for flexure and compression increased by 98% and 38% respectively compared to the reference mortar. Furthermore, the mixture having 0.12% volume had an increase in flexural and compressive strengths by 32% and 11%, respectively, while the increase in fracture energies for flexure and compression was 52% and 25%, respectively, compared to the reference mortar. The mechanisms of nanobiochar effect on flow, strength, and fracture energy were enlightened. The nanobiochars bridge the cracks, divert the cracks, act as hydration nucleation sites, enhance the matrix by its porous structure, and developed internal curing that led to increase in strength and fracture energy. This study suggests that the biochar produced from the apricot kernel shell has the potential to be used as a carbon sequestering mixture to improve performance of mortar and thereby utilizing waste as a construction material, contributing to the economy and environment.

Mild isolation and characterization of surface lignin from hydrothermally pretreated lignocellulosic forestry and agro-industrial waste biomass

Within the biorefining concept, the lignocellulosic biomass wastes can serve as feedstock to produce value-added chemicals and fuels. The sustainable valorization of biomass is based on integrated processes that aim to the utilization of “whole biomass”. To this end, the first step of the efficient biomass pretreatment towards selective isolation of cellulose, hemicellulose and lignin, is of paramount importance. Hydrothermal pretreatment of biomass in neat water is a green and well-established process that enhances hemicellulose removal and recovery in the liquid fraction, affording a cellulose and lignin enriched solid which can be enzymatically hydrolyzed to glucose. A simple and efficient method to facilitate the hydrolysis is the prior extraction of the formed “surface” lignin which hinders the action of enzymes. Within this context, in this work, forestry (beechwood sawdust) and agro-industrial (vine prunings, apricot kernel shells) wastes were hydrothermally pretreated in neat water (at 220 °C, 15 min) and the formed surface lignin was extracted via soxhlet or reflux methods under mild conditions, with the use of green solvents (ethanol, acetone). The delignification degree of the pretreated biomass was in the range of 35–67 wt%, depending on the solvent and biomass feedstock. The recovered surface lignins were of high purity and exhibited similar physicochemical and structural characteristics with the organosolv lignin. The fast pyrolysis of surface lignins afforded bio-oils enriched in alkoxy-phenols and oxy-aromatics. The biomass solids recovered after lignin extraction are enriched in cellulose (70%) and exhibit high relative crystallinity and improved textural properties, thus increasing their potential valorization.

Optimization of Polyphenol Extraction from Apricot Kernel Shells: Comparative Study Between Box-Behnken and Central Composite Designs

Background: Phenolic compounds, response surface methodology, optimization, apricot kernel shell, box-behnken design, central composite design. Objective: This study aimed to optimize the extraction of phenolic compounds from apricot kernel shells by different extraction techniques by studying the effects of different parameters on the extraction efficiency, and the comparison between the Box-Behnken Design and the Central Composite Design of the response surface methodology is done in order to have good extraction estimation. Methods: In this study, response surface methodology; Box-Behnken and Central Composite Designs, was used to contrast the efficacy and investigate the principal interactions of three operating parameters (ethanol concentration, microwave power, and extraction time), in the optimization of phenolic compounds extraction from apricot kernel shells by microwave-assisted extraction, ultrasonic-assisted extraction, and maceration techniques. Results: The results indicated that the optimal total phenolic compounds obtained with microwave assisted extraction techniques by Box-Behnken Design was 9.30 ± 0.22 mg/g, where the ethanol concentration, microwave power, and extraction time, were 45.85%, 370.5 W, and 11 min, respectively. However, the optimal total phenolic compounds revealed by Central Composite Design were 8.86 ± 0.05mg/g under ethanol concentration, microwave power, and extraction time of 51.99%, 394.37W, and 9.68min, respectively. Conclusion: This work proposes the best mathematical model to optimize the extraction of polyphenols from this by-product which seems to be a possible source of phenolic compounds that can be used in the food, cosmetic, and pharmaceutical industries.

Extraction of Melanin in Apricot Kernel Shell and the Optimization of Chelating Process of Its Metal Chelates

Extraction of Melanin in Apricot Kernel Shell and the Optimization of Chelating Process of Its Metal Chelates

Removing Pollutants from Sewage Waters with Ground Apricot Kernel Shell Material.

For the first time, a comprehensive review of the literature data on the use of apricot (Prunus armeniaca) biomass components as a sorption material for the treatment of wastewater and environmental water from various pollutants is carried out in the present study. In addition to a comprehensive analysis of contemporary studies, the current work carried out its own microstructural and energy dispersive studies. It shows that apricot kernel shell is a promising raw material for obtaining sorption materials that can be used to extract various pollutants from aqueous media. The parameters of sorption interaction are presented, at which the highest rate of removal of pollutants was achieved. It is shown that the sorption capacity of apricot biomass components can be increased by modifying it with various chemical reagents, as well as other physical and physicochemical methods. We reveal that most publications consider the use of the latter as a raw material for the production of activated carbons. It is established that the surface area and total pore space of activated carbons from apricot kernel shells depend on the modes of carbonization and activation. It is shown that activated carbons are effective adsorbents for removing various pollutants (metal ions, dyes, oil and oil products) from aqueous media. It was found that the adsorption isotherms of pollutants in most cases are best described by the Langmuir and Freundlich models, and the process kinetics is most often described by the pseudo-second-order model. The possibility of improving the sorption characteristics of apricot biomass during chemical or physicochemical treatment is also shown.

Preparation and Characterization of Apricot Kernel Shell Biochar and Its Adsorption Mechanism for Atrazine

In this study, the preparation of apricot kernel shell biochar by a hydrothermal method and its adsorption mechanism for atrazine was studied by scanning electron microscopy (SEM) and infrared spectrum (FTIR) analytical techniques. The results show that the biochar prepared from the apricot kernel shell has an evenly distributed, nonaggregated carbon microsphere structure and contains a large number of oxygen-containing groups. The higher the preparation temperature is, the more functional groups exist and the better the potential adsorption performance is. The adsorption kinetics of atrazine on apricot kernel shell biochar were fitted with a quasi-second-order kinetic equation (R2 ≥ 0.995, p < 0.05). The isothermal adsorption data were in accordance with the Freundlich model (R2 ≥ 0.911, p < 0.05). The adsorption of atrazine on apricot kernel shell biochar includes two processes: surface adsorption and diffusion. The adsorption capacity of apricot kernel shell biochar for atrazine increases with increasing preparation temperature and decreases with increasing pH and Ca2+ concentration. The adsorption mechanism includes hydrogen bonding and hydrophobic interactions. Therefore, biochar prepared from apricot shells, an agricultural waste, exhibits good adsorption performance for atrazine and has a good application prospect in addressing agricultural non-point source pollution, especially in pesticide residue pollution control.

Utilization of waste apricot kernel shell derived-activated carbon as carrier framework for effective shape-stabilization and thermal conductivity enhancement of organic phase change materials used for thermal energy storage

In this study, low-cost and eco-friendly AC obtained from waste apricot kernel shells (ACAS) was utilized to simultaneously solve the inherited drawbacks and enhance thermal conductivity of (Capric-Myristic acid (CA-MA), Lauryl alcohol (LAOH), n-Octadecane (OD) and Polyethylene glycol (PEG)) as different type organic PCMs. The ACAS/PCM composites had high PCM loading rates of up to 75 wt%, hence a high latent heat capacity of up to 193.7 J/g. Their melting and freezing temperatures varied in the range of 20.21–26.61 °C and 18.37–28.78 °C, respectively. All the prepared composites exhibited high thermal degradation resistance as well as high cycling stability even after 1200 melting-freezing cycles. The thermal conductivity of ACAS/CA-MA, ACAS/LAOH, ACAS/OD and ACAS/PEG was measured approximately 2.61, 2.40, 2.27 and 1.75 times higher than that of pure CA-MA, LAOH, OD and PEG, respectively. The advantageous TES characteristics of leak-proof composites make them favourable PCMs for low-temperature thermal management of buildings.

Сравнительный эколого-географический анализ кузниц большого пёстрого дятла Dendrocopos major (Aves: Piciformes) на севере и юге европейской части России

Сравнительный эколого-географический анализ кузниц большого пёстрого дятла Dendrocopos major (Aves: Piciformes) на севере и юге европейской части России

Metal-free catalyst fabrication by incorporating oxygen groups on the surface of the carbonaceous sample and efficient hydrogen production from NaBH4 methanolysis

In the present study, metal-free catalysts for efficient H2 generation from NaBH4 methanolysis was produced for the first time from apricot kernel shells with two-step activation. The first stage of the two-stage activation includes the production of activated carbon with the KOH agent (AKOH), and the second stage includes hydrothermally HNO3 activation with oxygen doping (O doped AKOH + N). The hydrogen production rate (HGR) and the activation energy (Ea) of the reaction with the obtained metal-free catalyst (10 mg) were determined as 14,444 ml min−1 g−1 and 7.86 kJ mol−1, respectively. The structural and physical-chemical properties of these catalysts were characterized by XRD (X-ray diffraction), SEM (scanning electron microscopy), elemental CHNS analysis, FT-IR (Fourier transform infrared spectroscopy), and nitrogen adsorption analysis. Also, the reusability results of this metal-free catalyst for H2 production are promising.

Utilization of activated carbons produced from some natural materials in the purification of used frying oil

The activated carbons (ACs) from shells of horse chestnut, chestnut, acorn, pistachio, apricot kernel, and wood shavings were evaluated to recover used oil (UO). The effects of the amount of AC, adsorption time, and temperature on the purification of the UO were investigated using the apricot kernel shells due to the high apricot production of Turkey. The kinetic evaluation was also done. The percentage improvements (PIs) in total polar materials (TPM), free fatty acids (FFA), p-anisidine value (p-AV), conjugated diene content (CD), and color of UO were found as 100, 56, 92, 51, and 90% for the apricot kernel AC in the column treatment. The most effective other ACs in decreasing FFA, p-AV, CD, and color were the horse chestnut (59%), chestnut (74%), chestnut (43%), and pistachio (72%), respectively. Consequently, these ACs can be used for the purification of UO. Practical applications Industrial wastes cause environmental pollution if they are ejected into river, sea, and soil. Therefore, they should be purified or treated for different purposes. In this study, the industrial wastes from the food and forest industries were used for the production of activated carbon to purify the used oil. The results showed that these activated carbons could be utilized for the regeneration of used oils. The most economical treatment is to blend the activated carbon with used frying oil for a certain time and remove it through centrifugation and filtration. The purified oil has the potential to be used in the biodiesel production.

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.