Peach Stones Research Articles

Detoxification of fermentable broth with activated biocarbon resulting from pyrolysis of agroforestry residues.

Carbon-like materials from pyrolysis (<500°C) of agricultural leftovers (rice husks, eucalyptus sawdust and peach stones) were submitted to steam activation and the expected adsorbent properties evaluated by means of a chemical method (methylene blue) and physically characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and surface area (BET). Batch experiments were carried out to check the pH effect on the adsorption of methylene blue, by evaluating the respective equilibrium isotherms (Langmuir, Freundlich and Temkin). The steam-activated biocarbons showed significant adsorbent capacity, which increased along with pH. The best performance was achieved by the activated biocarbon from peach stones, which showed adsorptive properties similar to activated carbon market. The suitable detoxification efficiency of untreated broths with activated biocarbon, and an increase in the required fermentability, supports the potential use of these adsorptive bioproducts from agricultural leftovers. The profitable use of agricultural waste materials is actually a welcome strategy for consolidating the biorefinery concept as well as ensuring planetary sustainability. PRACTITIONER POINTS: Use of biomass residues for detoxification of fermentable broth. The activated biocarbons showed significant adsorbent capacity similar to activated carbon market. The results revealed the potential of the biomass residues as a promising source within bio-refineries.

Biomass waste-derived nitrogen and iron co-doped nanoporous carbons as electrocatalysts for the oxygen reduction reaction

Biomass from agricultural by-products is gaining increasing interest as cheap and abundant precursor in the development of active materials for efficient and environmentally friendly devices like fuel cells. Herein, we investigated iron and nitrogen co-doped nanoporous carbons derived from aronia, peach stones and coal tar pitch/furfural as electrocatalysts for the electrochemical oxygen reduction reaction (ORR) in alkaline media. Urea was used as nitrogen precursor and two annealing steps with intermediate acid leaching served to activate the catalysts. Within the series, the peach stone-derived catalyst exhibited a catalytic activity for the ORR close to the benchmark Pt/C, with a 60 mV dec−1 Tafel slope upon the incorporation of 0.57 wt% Fe and proper combination of N-Fe species (20%) with pyridinic/pyridonic moieties (49%). We concluded that the microporosity and a certain content of meso/macro-pores of the activated carbon, together with the creation of graphitic domains result in a high relative amount of Fe-N4 and nitrogen functionalities, which determine the electrocatalytic performance.

Comparative Study of Kinetic Hydrodynamic Theoretical Model Results in Fluidized Bed Reactor Using Different Fuels.(Dept.M)

This work presents a comparative study on different biomass feedstock gasification in a fluidized bed using air. This work aims to study the effect of different biomass fuel types on the gasification performance in a fluidized bed, using kinetic hydrodynamic model results and similar experimental results. The feedstocks used in this study are sawdust pellets, Napier Grass, Portuguese Peach Stone, Chinese Coal /rice straw, solid waste wood, rice straw and olive kernels. The theoretical results were obtained from the kinetic-hydrodynamic simulation of the fluidized bed. The theoretical results were compared with published experimental results. The results showed that the syngas contents are strongly affected by the gasification temperature, equivalence ratio, and fuel characteristics. Increasing ER increases the char burning rate to produce more H2 even medium equivalence ratio (usually less than 0.36) and decreases again. CH4, CO, and H2 increased as temperature increased. From the fuel proximate analysis, the moisture contents affect the combustion reactions to generate more hydrogen. The lower H/C ratio gives greater heating value, as well as gives more concentrations of CO and CO2. In the case of using waste woody and rice straw, the significant increase of carbon monoxide (from 9% to 19%) and carbon dioxide (from 25% to 33.1%) is due to a higher C/O ratio in these biomasses analyses. The proximate analysis of feedstock and its contents from fixed carbons and volatiles matters affect strongly the producer gas concentrations, as a result, it’s LHV. The maximum relative error between model results and experimental results within range ±10.2%.

Use of Different Types of Biosorbents to Remove Cr (VI) from Aqueous Solution.

This article summarizes the results of a research study that was focused on the possibility of removing Cr (VI) from aqueous solution, using low-cost waste biomaterial in a batch mode. A set of seven biosorbents was used: Fomitopsis pinicola, a mixture of cones, peach stones, apricot stones, Juglans regia shells, orange peels, and Merino sheep wool. Three grain fractions (fr. 1/2, fr. 0.5/1.0, and fr. 0/0.5 mm) of biosorbents were studied. The aim was to find the most suitable biosorbent that can be tested with real samples. The influence of other factors on the course of biosorption was studied as well (chemical activation of the biosorbent, pH value, rotation speed during mixing, temperature, and the influence of biosorbent concentration). The use of chemical activation and adjustment of the pH to 1.1 to 2.0 make it possible to increase their sorption capacity and, for some biosorbents, to shorten the exposure times. Two kinetic models were used for the analysis of the experimental data, to explain the mechanism of adsorption and its possible speed control steps: pseudo-first and pseudo-second-order. The pseudo-second-order kinetic model seems to be the most suitable for the description of the experimental data. The thermodynamic parameters suggest that the biosorption was endothermic and spontaneous. In the biosorption equilibrium study, the adsorption data were described by using Langmuir and Freundlich adsorption isotherms. The Langmuir model was applicable to describe the adsorption data of all biosorbents. Both models are suitable for chemically treated sheep fleece and peach stones.

Removal of diesel pollution by biochar - support in water remediation

Water contaminated with diesel oil represents one of the greatest challenges in waste water management. Water soluble fraction (WSF) is of particular interest because of its toxicity to aquatic organisms and discharge regulations set by environmental authorities. Biochar sorbents have attracted great attention, due to their low cost origin and advantageous properties as well as high sorption capacities in sorption processes. In this study, we have reported the synthesis and characteristics of novel biochar sorbent made from waste lignocellulosic biomass (peach stones (PS)) and evaluated its possible application in removal of diesel WSF from synthetic water. Physiochemical characteristics of the biochar sample were analysed by scanning electron microscopy (SEM), Brunauer?Emmett?Teller (BET) method, and Fourier-transform infrared spectroscopy (FTIR), along with the elemental analysis. Characterisation of PS biochar (PS-B) indicated high multi porous surface area (159.1 m2 g-1) with the average pore diameter 2.7 nm. FTIR results indicated higher presence of aromatic compounds in PS-B as compared to PS. The sorption experiments performed in a batch system using PS-B resulted in more than 95 % removal of diesel WSF, reaching equilibrium after 5 h. Equilibrium data were well fitted by Freundlich isotherm, while the pseudo-second order equation fitted well the kinetic data, indicating chemisorption involving valency forces through the sharing/exchange of electrons between the sorbent and PS-B. Applications of ecotoxicology tests based on a microbial biosensor (Aliivibrio fischeri) have shown a significant toxicity reduction of water sample after the treatment with biochar.

Enrichment of the surface functional groups of activated carbon by modification method

The wastes formed from various industries' activities draw attention to their ability to be used as a natural adsorbent or as a source for activated carbon production. In this study, we aimed to produce activated carbon rich in surface functional groups from biomass. Surface functional groups of activated carbons (AC) were enriched by HNO3 oxidation. The activated carbons were synthesized with H3PO4 using peach stones (PSs), fruit juice industrial wastes, and can be found in abundance in the World and Turkey. The activated carbons' surface properties, such as BET surface area, micro-mesopore volume, and average pore diameter, were determined. The activated carbon with the highest surface area was produced with the impregnation ratio of 3/1 at 400 °C (3AC400) as 1399 m2/g. The microporous structures of the 3AC400 synthesized were determined to be more than the mesopore structures. The effects of acid modification on the surface of 3AC400, whose surface characterization was completed, were investigated using HNO3 at different concentrations (15, 30, 45, and 69% (v/v) HNO3). When the nitric acid concentration used in the modification was increased from 15% to 69%, the BET surface area of pure activated carbon (3AC400) decreased from 1399 m2/g to 15.44 m2/g. Besides, the micropores were wholly clogged, and the mesopore volume decreased from 0.127 cm3/g to 0.042 cm3/g. Vmic/Vtop of 3AC400 was reduced from 0.813 to 0.008. Modification using in this study was found to have a significant effect on the surface area of 3AC400. Nitric acid led micropores to collapse. So the structure of the surface of modified activated carbons has become more mesopores. The surface properties and surface functional group diversity of the synthesized modified activated carbons by various methods were investigated. With 69% nitric acid modification, the amount of carboxyl, lactone, and phenyl groups on the activated carbon surface was increased by 5.3, 9.75, and 9.00, respectively. The nitric acid modification affected the diversity of surface functional groups such as lactone> phenol> carboxyl. As the nitric acid concentration increased, the modified samples' total surface acidity increased, and IEP values shifted from 3.6 to the left. The total acidity value for the 69NAC/90/2 sample has increased approximately seven times that of the total acidity value of 3AC400.

Influence of calcium species on SO2 adsorption capacity of a novel carbonaceous materials and their ANN modeling

Due to the sulfur dioxide (SO2) negative effects to the environment and human health, its removal is currently of great importance to policy markers and researchers. In this context, the present work had the aim to study the SO2 dynamic adsorption behavior on two activated carbons rich on calcium species. One material prepared directly from peach stone shell (PC) and the other prepared from raw material treated with CaCl2 (PCCa) with the purpose to increase the interaction of sulfur with calcium compounds on the surface and to augment its surface area. The obtained activated carbons were characterized using N2 adsorption at 77 K, IR, XRD and SEM/EDX analysis. PCCa carbon presented the higher adsorption capacity compared with PC material, indicating that the surface area and the increase of calcium groups (Ca(OH)2, CaCO3, CaO) are playing an important role during the adsorption of SO2. Additionally, the results demonstrated that as temperature increases the adsorption capacity decreases. On the other hand, the dynamic studies revealed that the residence time reached at 150 mL min−1 flow-rate was the most efficient for the mass transfer processes. Also, the results demonstrated that the presence of moisture decreases the adsorption capacity due to the presence of water molecules on the adsorbent surface. The dynamic adsorption results were modeled using: the Advection-dispersion model, FANN and the conventional models Thomas and Yan. The results shown that the FANN model was the best to correlate the adsorption breakthrough curves of SO2.

Nano-ZrO2/TiO2 Impregnated Orange Wood Sawdust and Peach Stone Shell Adsorbents for Cr (VI) Removal

Background: In this work, Cr (VI) adsorption on nano-ZrO2๏TiO2 impregnated orange wood sawdust (Zr๏Ti/OWS) and nano-ZrO2๏TiO2 impregnated peach stone shell (Zr๏Ti/PSS) was investigated by applying different adsorption parameters such as Cr (VI) concentrations, contact time, adsorbent dose, and pH for all adsorbents. Methods: The adsorbents were characterized by SEM and FT-IR. The equilibrium status was achieved after 120 min of contact time and optimum pH value around 2 were determined for Cr (VI) adsorption. Adsorption data in the equilibrium is well-assembled by the Langmuir model during the adsorption process. Results: Langmuir isotherm model showed a maximum adsorption value of OWS: 21.65 mg/g and Zr๏Ti/OWS: 27.25 mg/g. The same isotherm displayed a maximum adsorption value of PSS: 17.64 mg/g, and Zr๏Ti/PSS: 31.15 mg/g. Pseudo-second-order kinetic models (R2=0.99) were found to be the best models for describing the Cr (VI) adsorption reactions. Conclusıon: Thermodynamic parameters such as changes in ΔG°, ΔH°, and ΔS° have been estimated, and the process was found to be spontaneous.

Comparison of Adsorption Properties of Activated Carbons with Different Crops Residues as Precursors for Gold Cyanide Recovery: An Iranian Gold Industry Guide

Adsorption of gold cyanide on three types of Activated Carbons (ACs) has been investigated in batch and column adsorption conditions. Applied ACs have been derived from different crops precursors i.e., coconut shell (CAC), peach stone (PAC), and walnut shell (WAC). As peach stone and walnut shells are abundant agricultural residues in Iran, the activated carbons produced from these precursors are economically preferable for the gold recovery process. The ACs were characterized using FTIR, SEM, BET, and Wet-Bed Compaction Hardness analyses. Batch equilibrium adsorption data were analyzed using the Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherm models. Freundlich isotherm was in better agreement with the equilibrium data and the maximum adsorption capacity (40.8 mg/g) was tabulated for CAC. Adsorption kinetics was also modeled using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. The PAC recorded the highest removal rate in the light of better agreement of the pseudo-second-order model. Fixed-bed column experiments were carried out at different initial gold concentrations (30, 50 mg/L) to determine the characteristics of the breakthrough curves. The maximum bed capacity (37.55 mg/g) was obtained for CAC. Three dynamic adsorption models including, Thomas, Yoon–Nelson, and Adam–Bohart,were applied to describe the breakthrough curves. Both Thomas and Yoon–Nelson models were in appropriate agreement with the experimental column adsorption data. This research introduces peach stone as a promising precursor considering availability, technical features, and economical aspects for the production of AC for gold recovery from cyanide leach solutions. Results are also conducive for gold mining industries to select the appropriate activated carbon.

Ni0.5M0.5Fe2O4 (M = Cu, Zn) Ferrites Hosted in Nanoporous Carbon from Waste Materials as Catalysts for Hydrogen Production

This work is focused on the preparation of Ni0.5M0.5Fe2O4 mixed ferrites (M = Zn or Cu), supported on nanoporous carbons materials. The carbon supports are obtained from various waste residues, such as peach stones from the canning industry and by-products from the low rank coals pyrolysis. X-ray diffraction (XRD), nitrogen physisorption, high-resolution transmission electron microscopy (HRTEM), Moessbauer spectroscopy and temperature programmed reduction (TPR) analyses as well as mesoporous silica with tridimensional structure type KIT-6 silica based reference samples are used for detail characterization of the obtained materials. It was established that the loaded on the carbon supports phase is a complex mixture of finely dispersed ferrite, substituted magnetite, metal (Cu, Fe, FeNi alloy) and ZnO particles. Their dispersion and composition depend on the texture characteristics of the carbon support, which could be easily controlled by the waste precursor used. The existence of mesoporosity in the carbon host matrix provokes the formation of more finely dispersed and easily reducible spinel particles, which ensures higher initial catalytic activity, but fast deactivation of the catalysts. The formation of activated carbon mesoporosity is facilitated by the presence of cellulose and hemicellulose in the biomass or the addition of furfural to the coal tar pitch precursor. The Ni0.5Zn0.5Fe2O4 modifications demonstrate higher potential as catalysts for hydrogen production via methanol decomposition.

Atrazine removal in aqueous solutions using activated carbon from peach stone

Activated carbon is commonly used as a material for contaminant-adsorption processes in aqueous systems. However, its use is more restricted to charcoal than to coal, for the most part, in view of the fact of the higher cost (~ 40%) if the mineral is a fossil fuel which needs to be extracted from the earth by mining. For this reason, the peach stone that comes from alimentary industrial tailings can be a good choice for the separation of pollutants from aqueous suspensions and other soluble substances. The purpose of this research was the development of a low-cost filter, using stones to remove atrazine from water. Appraisal and characterization studies were performed along with batch experiments to investigate dosing effects of the activated carbon, atrazine concentration, contact time, and adsorption pH on removal procedures. From the results of the experiment, an excellent removal of the analyte in question was observed under conditions that can be considered as close as possible to the environment, such as pH = 6.5, room temperature and 10 minutes of agitation time, always choosing the best alternative with the lowest cost of energy and time. Batch system application has been recommended as versatile for utilization in seasonal problems such as pesticide contamination.

Integration of Peach (Prunus persica L.) Residues, Beneficial Microbes and Phosphorous Enhance Phenology, Growth and Yield of Soybean

Two years consecutive field experiments were conducted at Agriculture Research Institute Mingora Swat, Pakistan in summer seasons of 2016 (year 1) and 2017 (year two) on soybean (cv. Malakand-96) crop. The design was used randomized complete block design (RCBD) with three replications. Experimental treatments were used, peach residues (leaves and fruits having no stones (partially decomposed), its well decomposed compost comprised of leaves and fruits having no stones and its biochar (peach tree stem, with peach stones, leaves and twigs), three phosphorus (P) levels and two beneficial microbes PSB and Trichoderma. Results revealed that peach organic sources and soil application of Trichoderma and phosphorous enhanced soybean phenology and yield. Days to emergence and emergence m–2 was non-significantly affected by P levels, organic sources and beneficial microbes, although number of branches and number of leaves plant–1 responded positively to organic sources, P levels and beneficial microbes application. Soybean seed yield was increased with organic sources, phosphorous levels and beneficial microbe’s inoculation. Highest seed yield was produced with compost amendments having at par valued with biochar, while P at the rate of 75 and 100 kg ha–1 produced at par value seed yield. Among beneficial microbes, soil applied Trichoderma was far better than seed inoculation with PSB. Regression analysis was carried for all the treatments and concluded that soybean seed yield increased with rest plots as compared to control.

Syngas production strategies from biomass gasification: Numerical studies for operational conditions and quality indexes

Gasification is an enhanced thermal technique, as it affords a versatile synthetic gas (syngas) from which it is possible to obtain various commodity assets such as electricity, fuels and chemicals while conveniently disposing of biomass or waste residues.To the best of the authors’ knowledge, there are no publications thoroughly relating syngas quality features with its possible applications. The report of quality indexes for syngas is quite scarce once they depend on quality indicators which are difficult to reconcile and simultaneously adjust to meet the expected syngas characteristics. Therefore, in an attempt to fill this gap, this work reports the gasification modelling for miscanthus (M), peach stone (PS) and a mixture of polyethylene terephthalate and vine pruning (PET-VP) in order to determine syngas quality indicators and potential applications. The operational conditions were optimized through a parametric study for the achievement of high-quality syngas, varying temperature (T), equivalence ratio (ER) and steam to biomass ratio (SBR) and assessing the lower heating value (LHV), cold gas efficiency (CGE) and tar content.The main trends for the assessed parameters show improved calorific content for higher temperatures (800 °C – 850 °C), lower ER (0.2–0.25) and moderate SBR values (around 2.0). PET-VP displayed the higher LHV (around 9 MJ/Nm3) except when SBR was varied. In this case, M afforded enhanced calorific content (6.5 MJ/Nm3) which rapidly decreased for higher ratios. Conversion efficiencies of 70–80% were seen for the studied feedstocks and tar content was seen to decrease for higher temperatures, higher ER and higher SBR. PET-VP enabled the manufacture of chemicals and fuel gas, while M and PS originated syngas capable of producing synthetic fuels.

Removal of imidacloprid pesticide using nanoporous activated carbons produced via pyrolysis of peach stone agricultural wastes

This study describes the preparation of nanoporous activated carbons from the agricultural waste of peach stones. These materials were utilized as adsorbents for removing imidacloprid pesticide from aqueous media. Two types of activated carbons (PSAC 300 and PSAC 500) were synthesized via chemical activation with orthophosphoric acid followed by pyrolysis at 300 and 500 °C, respectively. Brunauer, Emmet, and Teller (BET) analysis revealed a mesoporous structure for PSAC 500 with lower surface area and pore volume than that of the microporous PSAC 300. Both PSAC 300 and PSAC 500 successfully removed imidacloprid with removal efficiencies of about 80% and 99%, respectively, at 10 mg/L of imidacloprid and pH 5.2, while PSAC 500 exhibited a maximum adsorption capacity of 39.37 mg/g. Fourier transform infrared (FTIR) spectroscopy measurements along with thermodynamic calculations inferred that physisorption occurred via hydrogen bonding and pi–pi stacking. The two activated carbons were successfully regenerated and reused for three consecutive cycles. This work has implications for waste valorization and production of value-added products from waste.

Etodolac adsorption onto activated carbon prepared by chemical activation and pyrolysis of biomasses mixture

In this study, a novel microporous activated carbon (AC) from low-cost biomasses (apricot and peach stones, and almond shell) mixture by FeSO4 activation and following pyrolysis was synthesized, characterized, and tested for etodolac (ETD) adsorption. The characteristics of AC were determined by BET surface area, total pore volume, average pore size, surface functional group analysis by Boehm’s titration and FTIR, and SEM-EDX. A high-quality activated carbon with 958.57 m2/g surface area, 0.4796 cm3/g total pore volume, and 1.9963-nm average pore size could be successfully synthesized from the mixture activated by FeSO4 at impregnation ratio of (FeSO4/precursor (w/w)) 0.5. ETD adsorption ability of the prepared AC was investigated depending on the effects of AC dosage, contact time, pH, initial ETD concentration, and temperature. Also, the linear and nonlinear forms of Langmuir and Freundlich isotherms and pseudo-first-order and pseudo-second-order kinetic models were compared to get the best isotherm and kinetic model. The results showed that more than 95% ETD adsorption could be achieved at the presence of 5 g/L of AC, contact time of 150 min, and at a wide pH range. The adsorption data was found to be best fitted to the nonlinear pseudo-second-order kinetic model and nonlinear Freundlich isotherm. The adsorption of ETD onto the AC was found to be exothermic and spontaneous.

Competitive adsorption of methylene blue and Pb (II) ions on the nano-magnetic activated carbon and alumina

The adsorption of methylene blue (MB) in single and binary solutions were investigated on new promising functionalized magnetic wood based activated carbon (MFMWAC), peach stone activated carbon (MFMPAC) and alumina (MFMA) derived by a facile preparation method. Characterization of the magnetic nano-adsorbents was achieved by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), Vibrating sample magnetometer (VSM) and zeta potential tests. Findings revealed that the core-shell magnetite nanocomposites were formed with size of less than 50 nm. The kinetic and isotherm models were also analyzed for the adsorption of MB. Equilibrium adsorption was evaluated employing Langmuir and Freundlich equations, in which Freundlich model was in good agreement with the experimental results. Maximum adsorption capacities of MFMWAC, MFMPAC and MFMA were measured as 434.13, 437.78 and 196.08 mg/g for MB, respectively. The pseudo second order kinetic with higher correlation coefficient indicated a better fit with MB adsorption. Competitive adsorption of MB disclosed that the adsorption capacities of the carbonaceous adsorbents for MB reduced considerably by adding the Pb (II) ions to the aqueous solutions. However, the remarkable capacity of MB was calculated to be 175.39 and 182.45 mg/g by using the extended Langmuir for MFMWAC and MFMPAC, respectively in the binary solution. Reusability of the magnetic adsorbent was also investigated in the competitive adsorption for six cycles which showed that the prepared adsorbent can be used for the real applications.

Nanoporous Activated Carbons Derived from Peach Stones

In this work, nanoporous activated carbons from Peach Stone powder was achieved using phosphoric acid as an activating agent and carbonization has been conducted at temperatures ranging from 400oC to 700oC using Nitrogen as inert gas in a tubular furnace, to understand the effect of the adsorption capacity with variation in temperature. Evaluation of microporosity of each of these specimens was performed by Iodine Number technique, of which the results showed a maximum amount of micropores in the carbon at the carbonization temperature of 500oC. The morphology of the carbon samples at two extreme temperatures of 400oC and 700oC was studied using FE-SEM images, which demonstrated large amount of nanoporous in the carbon surfaces at the higher temperature. Raman Spectroscopy outcomes delineate the similar amorphous nature of the carbonaceous specimen at these temperatures with both G band and D band. These results indicate a potential to develop a good adsorbent material applicable for water purification.

Peach Brown Rot

Brown rot, caused by Monilinia spp., is one of the most economically harmful fungal diseases for peach and other stone fruit growers worldwide. Under the right conditions, the entire tree’s crop can be completely rotted. Fruit susceptibility fluctuates with the various stages of development; mature fruits are highly susceptible to disease, and fruit infection has the greatest impact on production. This new 7-page publication of the UF/IFAS Horticultural Sciences Department describes the disease cycle, symptoms, and management options available for brown rot in Florida peaches. Written by Ali Sarkhosh, Shirin Shahkoomahally, Logan Marie Richmond-Cosie, and Philip Harmon. https://edis.ifas.ufl.edu/hs1357

Investigation of Characteristics and Thermal Behaviour of Lignocellulosic Waste Biomass Using Thermogravimetric Analysis

This paper focuses on lignocellulosic waste biomass originating from food industry, which should find its further application in order to fulfill demands of circular economy. Therefore, here are presented some of the chemical and physical properties that affect combustion process, as well as thermochemical reaction kinetics for lignocellulosic biomass wastes. The biomass investigated was peach stone particles originating from food industry. The results have showed that peach stones can be characterized as good energy alternative renewable material, with properties that allow its safe thermochemical conversion. Kinetic analysis of this biomass was performed using Thermogravimetric Analysis (TGA) with a simple reaction model applied, namely n-th order reaction model. The obtained results have confirmed the complex nature of this material and the need for further modelling.

Cold oxygen plasma induces changes on the surface of carbon materials enhancing methanogenesis and N2O reduction in anaerobic sludge incubations

AbstractBACKGROUNDConductive materials, such as activated carbon (AC), graphene and biochar, have recently been applied for enhancing methane (CH4) production in anaerobic digesters. However, few efforts have been made to develop engineered conductive materials for these purposes. The aim of this work was to synthesize carbon materials from pecan nut shells and peach stones to apply them in anaerobic sludge incubations for enhancing the methanogenic activity, as well as the reduction of nitrous oxide (N2O).RESULTAddition of conductive materials increased up to six‐fold the maximum CH4 production rate. Moreover, oxidation of these carbon materials with cold oxygen plasma enriched their surface with redox functional groups (e.g. quinones), so that their application further increased the methanogenic production rate up to 11‐fold as compared to controls lacking conductive materials. Furthermore, the reduction rate of N2O was increased several orders of magnitude in the presence of synthesized carbon materials, which constitutes the first demonstration that conductive materials can significantly increase the reduction rate of this greenhouse gas.CONCLUSIONResults indicate that there is great potential to develop engineered conductive materials to enhance both the production of CH4 and the reduction of N2O from wastewater treatment plants (WWTP), which may contribute to achieve more efficient processes. © 2019 Society of Chemical Industry