Influence of pyrolysis temperature on the characteristics and lead(II) adsorption capacity of phosphorus-engineered poplar sawdust biochar

AbstractMarabu (Dichrostachys cinerea) from Cuba and aspen (Populus tremula) from Britain are two rosid angiosperms that grow easily, as a weed and as a phytoremediator, respectively. As part of scientific efforts to valorise these species, their barks and woods were pyrolysed at 350, 450, 550 and 650 °C, and the resulting biochars were characterised to determine the potential of the products for particular applications. Percentage carbon composition of the biochars generally increased with pyrolysis temperature, giving biochars with highest carbon contents at 650 °C. Biochars produced from the core marabu and aspen wood sections had higher carbon contents (up to 85%) and BET surface areas (up to 381 m2 g−1) than those produced from the barks. The biochar porous structures were predominantly mesoporous, while micropores were developed in marabu biochars produced at 650 °C and aspen biochars produced above 550 °C. Chemical and thermal activation of marabu carbon greatly enhanced its adsorption capacity for metaldehyde, a molluscicide that has been detected frequently in UK natural waters above the recommended EU limit.

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Potential of Novel Biochars Produced from Invasive Aquatic Species Outside Food Chain in Removing Ammonium Nitrogen: Comparison with Conventional Biochars and Clinoptilolite

Sustainability ◽

10.3390/su11247136 ◽

2019 ◽

Vol 11 (24) ◽

pp. 7136 ◽

Cited By ~ 4

Author(s):

Haihong Song ◽

Jianming Wang ◽

Ankit Garg ◽

Xuankai Lin ◽

Qian Zheng ◽

...

Keyword(s):

Adsorption Capacity ◽

Adsorption Kinetics ◽

Water Hyacinth ◽

Pyrolysis Temperature ◽

Ammonium Nitrogen ◽

Pig Manure ◽

Agricultural Residue ◽

Batch Tests ◽

Lower Temperature ◽

Feedstock Availability

Previous studies for removal of ammonium from wastewater were mainly conducted using biochars produced from agricultural residue. Feedstock type (agricultural residue, wood, animal waste, and aquatic waste), as well as pyrolysis temperature, can significantly influence biochar properties and hence its adsorption capacity. Such studies are useful in decision making for selecting biochar depending on feedstock availability and pyrolysis temperature. This study aims to explore the effects of different types of biochar (laboratory prepared novel water hyacinth and algae biochar, conventional cedar wood, rice straw, and pig manure biochar) on the adsorption kinetics for ammonium removal from wastewater. The adsorption kinetics of biochars were compared to that of commercially available clinoptilolite and interpreted with their respective physicochemical properties (SEM, FTIR, XRD). Batch tests were performed to evaluate the effects of biochars on adsorption of ammonium nitrogen at different concentrations (10 mg/L and 100 mg/L). The tests reveal that clinoptilolite has the highest adsorption capacity. Among biochars, pig manure (animal based) biochar has a higher adsorption capacity in comparison to conventional agricultural residues based biochars. The capacity of pig manure biochar under highly concentrated ammonium solution (100 mg/L) is merely 20% lower than that of clinoptilolite. Both water hyacinth and algae biochar produced at higher temperature (600 °C) show higher sorption rate and capacity (depending on the initial concentration of ammonium) for ammonium in comparison to that produced at a lower temperature (300 °C). This is likely due to an increase in porosity at higher temperatures of pyrolysis.

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Preparation of lignin-based mesoporous biochar nano- and microparticles, and their adsorption properties for hexavalent chromium

BioResources ◽

10.15376/biores.16.3.6363-6377 ◽

2021 ◽

Vol 16 (3) ◽

pp. 6363-6377

Author(s):

Yu Hu ◽

Meng Ling ◽

Xianfa Li

Keyword(s):

Adsorption Capacity ◽

Functional Groups ◽

Pyrolysis Temperature ◽

Waste Water Treatment ◽

Bet Surface Area ◽

Isotherm Models ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Contaminated Waste ◽

Mesoporous Biochar

The removal performance and mechanism of Cr(VI) from aqueous solution was studied for a novel micro-nano particle kraft lignin biochar (BC) pyrolyzed at 400 to 700 °C. The physicochemical properties of BC were determined by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and N2 adsorption-desorption isotherms. The results illustrated that the BC had irregular micro- and nanoparticles with abundant pore structure and high BET surface area (111.1 m2/g). The FT-IR results showed that the lower pyrolysis temperature resulted in more oxygen-containing functional groups. The Cr(VI) adsorption capacity decreased with the pyrolysis temperature increasing from 400 to 700 °C, and the maximum percentage removal of Cr(VI) for BC obtained at 400 °C was 100% at pH 2, which suggested that the removal efficiency was mainly dependent on functional groups. Kinetic analysis demonstrated that Cr(VI) adsorption on BC fit well to the pseudo-second-order kinetic model. The adsorption data was well fitted with the Langmuir isotherm models, and the maximum adsorption capacity was 37.2 mg/g at 298K. The BC could be reused twice with Cr(VI) removal of 63.91% and was suitable for Cr(VI) contaminated waste-water treatment.

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Biochar properties and lead(II) adsorption capacity depend on feedstock type, pyrolysis temperature, and steam activation

Chemosphere ◽

10.1016/j.chemosphere.2019.05.128 ◽

2019 ◽

Vol 231 ◽

pp. 393-404 ◽

Cited By ~ 39

Author(s):

Jin-Hyeob Kwak ◽

Md Shahinoor Islam ◽

Siyuan Wang ◽

Selamawit Ashagre Messele ◽

M. Anne Naeth ◽

...

Keyword(s):

Adsorption Capacity ◽

Pyrolysis Temperature ◽

Steam Activation

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Phosphorus and Nitrogen Adsorption Capacities of Biochars Derived from Feedstocks at Different Pyrolysis Temperatures

Water ◽

10.3390/w11081559 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1559 ◽

Cited By ~ 4

Author(s):

Lei Zhou ◽

Defu Xu ◽

Yingxue Li ◽

Qianchen Pan ◽

Jiajun Wang ◽

...

Keyword(s):

Adsorption Capacity ◽

Adsorption Process ◽

Pyrolysis Temperature ◽

Nitrogen Adsorption ◽

P Adsorption ◽

Adsorption Capacities ◽

Plant Waste ◽

Endothermic Reactions ◽

Egg Shell ◽

Feedstock Material

This study investigates the P and NO3− adsorption capacities of different biochars made from plant waste including rice straw (RSB), Phragmites communis (PCB), sawdust (SDB), and egg shell (ESB) exposed to a range of pyrolysis temperatures (300, 500 and 700 °C). Results indicate that the effect of pyrolysis temperature on the physiochemical properties of biochar varied with feedstock material. Biochars derived from plant waste had limited adsorption or even released P and NO3−, but adsorption of P capacity could be improved by adjusting pyrolysis temperature. The maximum adsorption of P on RSB700, PCB300, and SDB300, produced at pyrolysis temperature of 700, 300 and 300 °C, was 5.41, 7.75 and 3.86 mg g−1, respectively. ESB can absorb both P and NO3−, and its adsorption capacity increased with an increase in pyrolysis temperature. The maximum NO3− and P adsorption for ESB700 was 1.43 and 6.08 mg g−1, respectively. The less negative charge and higher surface area of ESB enabled higher NO3− and P adsorption capacity. The P adsorption process on RSB, PCB, SDB and ESB, and the NO3− adsorption process on ESB were endothermic reactions. However, the NO3− adsorption process on RSB, PCB and SDB was exothermic. The study demonstrates that the use of egg shell biochar may be an effective way to remove, through adsorption, P and NO3− from wastewater.

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Effect of temperature and duration of pyrolysis on spent tea leaves biochar: physiochemical properties and Cd(II) adsorption capacity

Water Science & Technology ◽

10.2166/wst.2020.309 ◽

2020 ◽

Vol 81 (12) ◽

pp. 2533-2544

Author(s):

Zhanbiao Yang ◽

Xincong Liu ◽

Mengdi Zhang ◽

Lixia Liu ◽

Xiaoxun Xu ◽

...

Keyword(s):

Adsorption Capacity ◽

Pyrolysis Temperature ◽

Low Cost ◽

Total Yield ◽

Effect Of Temperature ◽

Surface Porosity ◽

Tea Leaves ◽

Physiochemical Properties ◽

Pseudo Second Order ◽

Spent Tea Leaves

Abstract We analyzed the effects of pyrolysis temperature and duration on the physiochemical properties and Cd(II) adsorption capacity of spent tea leaves (STL) biochar. The STL biochar was produced by pyrolysis at 300, 400, 500 and 600 °C for 1 and 2 h. The pyrolysis temperature was positively correlated to the ash content, pH, electrical conductivity, specific surface area (SBET), pore volume (PV) and C content, and negatively with the total yield, O, H and N content, and the O/C and H/C atomic ratios. Furthermore, the surface porosity of STL biochar increased, the density of oxygen-containing functional groups decreased, and the formation of aromatic structures was enhanced at higher pyrolysis temperatures. The adsorption of Cd(II) onto STL biochar fitted with the pseudo-second-order kinetics and Langmuir isotherms model. The STL biochar produced at 600 °C for 2 h showed the maximum Cd(II) adsorption capacity of 97.415 mg/g. In addition, Cd(II) adsorption was mainly physical and occurred in monolayers. Thus, STL biochar is a suitable low-cost adsorbent for wastewater treatment.

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Greenhouse Crop Residue and Its Derived Biochar: Potential as Adsorbent of Cobalt from Aqueous Solutions

Water ◽

10.3390/w12051282 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1282 ◽

Cited By ~ 3

Author(s):

Irene Iáñez-Rodríguez ◽

Mónica Calero ◽

Gabriel Blázquez ◽

María Ángeles Martín-Lara

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Crop Residue ◽

Pyrolysis Temperature ◽

Low Cost ◽

Treatment Temperature ◽

Cobalt Removal ◽

Equilibrium Data ◽

Different Temperatures ◽

And Behavior

This work is focused on the removal of cobalt from aqueous solutions using the greenhouse crop residue and biochars resulting from its pyrolysis at different temperatures, which have not been previously used for this purpose. This study aims to provide insights into the effect of pyrolysis temperature as a key parameter on the cobalt adsorption capacity of these materials. Firstly, the main physicochemical properties of greenhouse crop residue and its biochars prepared under different pyrolysis temperatures were characterized by elemental analysis and FT-IR, among others. Then, the cobalt adsorption capacity of materials was evaluated in batch systems. The best results were obtained for the biochar prepared by pyrolysis at 450 °C (adsorption capacity of 28 mg/g). Generally, the adsorption capacity of the materials increased with pyrolysis temperature. However, when the treatment temperature was increased up to 550 °C, a biochar with worse properties and behavior than cobalt adsorbent was produced. Rather than surface area and other physical properties, functional groups were found to influence cobalt adsorption onto the prepared materials. The adsorption kinetics showed that the adsorption followed pseudo-second-order kinetics model. The obtained equilibrium data were fitted better by the Langmuir model rather than the Freundlich model. Finally, decomposition of loaded-materials was analyzed to assess their possible recycling as fuel materials. The study suggested that greenhouse crop residue can be used as a low-cost alternative adsorbent for cobalt removal from aqueous solutions.

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Modeling and Optimization of Biochar Based Adsorbent Derived from Kenaf Using Response Surface Methodology on Adsorption of Cd2+

Water ◽

10.3390/w13070999 ◽

2021 ◽

Vol 13 (7) ◽

pp. 999

Author(s):

Anwar Ameen Hezam Saeed ◽

Noorfidza Yub Harun ◽

Suriati Sufian ◽

Muhammad Roil Bilad ◽

Baiq Asma Nufida ◽

...

Keyword(s):

Experimental Data ◽

Adsorption Capacity ◽

Pyrolysis Temperature ◽

Removal Rate ◽

Specific Area ◽

Heating Time ◽

Impregnation Ratio ◽

Activated Biochar ◽

Correlation Models ◽

Positive Effect

Cadmium is one of the most hazardous metals in the environment, even when present at very low concentrations. This study reports the systematic development of Kenaf fiber biochar as an adsorbent for the removal of cadmium (Cd) (II) ions from water. The adsorbent development was aided by an optimization tool. Activated biochar was prepared using the physicochemical activation method, consisting of pre-impregnation with NaOH and nitrogen (N2) pyrolysis. The influence of the preparation parameters—namely, chemical impregnation (NaOH: KF), pyrolysis temperature, and pyrolysis time on biochar yield, removal rate, and the adsorption capacity of Cd (II) ions—was investigated. From the experimental data, some quadratic correlation models were developed according to the central composite design. All models demonstrated a good fit with the experimental data. The experimental results revealed that the pyrolysis temperature and heating time were the main factors that affected the yield of biochar and had a positive effect on the Cd (II) ions’ removal rate and adsorption capacity. The impregnation ratio also showed a positive effect on the specific surface area of the biochar, removal rate, and adsorption capacity of cadmium, with a negligible effect on the biochar yield. The optimal biochar-based adsorbent was obtained under the following conditions: 550 °C of pyrolysis temperature, 180 min of heating time, and a 1:1 NaOH impregnation ratio. The optimum adsorbent showed 28.60% biochar yield, 69.82% Cd (II) ions removal, 23.48 mg/g of adsorption capacity, and 160.44 m2/g of biochar-specific area.

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Research on Cadmium Adsorption-Desorption Dynamics of Biochars

10.20944/preprints202106.0720.v1 ◽

2021 ◽

Author(s):

Zhenyu Zhang ◽

Shu Dang ◽

Guiping Zheng ◽

Haibo Li

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Pyrolysis Temperature ◽

Particle Diffusion ◽

Aqueous Environment ◽

Order Model ◽

Film Diffusion ◽

Diffusion Stage ◽

Intra Particle Diffusion ◽

Adsorption Desorption

Biochar has high potential usage in retaining various contaminants, wastewater treatment, and water purification. In this study, three rice husk derived biochars with pyrolysis temperature 300, 400 and 500 ºC, respectively, and pristine rice rusk were used to remove cadmium from aqueous solution. The results showed that about 70% or more of Cd2+ adsorption occurred in the first 960 mins of adsorption kinetics. The Cd2+ adsorption capacity under equilibrium increased with increasing pyrolysis temperature, probably attributed to the increased specific surface area (SSA) under higher pyrolysis temperature noting that significant linear correlation occurred between Cd2+ adsorption capacity and SSA. The Cd2+ adsorption could be best fitted by pseudo-second order model relative to Elovich model and pseudo-first order model. The Cd2+ adsorption rates were higher in ﬁlm diffusion stage, indicating that ﬁlm diffusion stage was signiﬁcant and fast in the early stage of Cd2+ adsorption. In contrast, Cd2+ adsorption by intra-particle diffusion accounted for 47.0%, 47.9% and 43.9% on average of the total Cd2+ adsorption, respectively, indicating that intra-particle diffusion of Cd2+ played a more predominant role in limiting Cd2+ adsorption rate. When reaching Cd2+ desorption equilibrium, removal ratio (RR) values were averaged 0.96, 0.91, and 0.90 under three initial concentrations. More than 90 percentage on average of Cd2+ was removed from aqueous solution by biochars and rice rusk as well, thus biochars can be used to efficiently remove contaminants from aqueous environment. Cation exchange, electrostatic attraction, and the complexation with surface functional groups could be the main dominant mechanisms for Cd2+ adsorption-desorption on biochars.

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Characterization and Use of Char Produced from Pyrolysis of Post-Consumer Mixed Plastic Waste

Water ◽

10.3390/w13091188 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1188

Author(s):

M. A. Martín-Lara ◽

A. Piñar ◽

A. Ligero ◽

G. Blázquez ◽

M. Calero

Keyword(s):

Adsorption Capacity ◽

Pyrolysis Temperature ◽

Aqueous Media ◽

Great Influence ◽

Product Yield ◽

Plastic Waste ◽

Volatile Content ◽

Solid Product ◽

Initial Concentration ◽

Equilibrium Study

In this work, the pyrolysis of post-consumer mixed plastic waste (polypropylene (PP), polystyrene (PS) and polyethylene film (PE)) is carried out. The solid product of the pyrolysis is characterized and tested for its use as adsorbent of lead present in aqueous media. The pyrolysis temperature has a great influence on the solid product yield, decreasing when the temperature increases. The highest yield to solid product obtained is from the pyrolysis of film at lower temperature (450 °C), reaching almost 14%. The results of product solid characterization reveal that the carbon, hydrogen and nitrogen content decreases with increasing pyrolysis temperature. Furthermore, both the ash and the volatile content are related to the pyrolysis temperature. The ash content is higher when the pyrolysis temperature is higher, while when the temperature increases, a solid product with lower volatile content is obtained. In respect to specific surface area, a higher pyrolysis temperature improves the properties of the solid product as an adsorbent. The adsorption capacity increases as the pyrolysis temperature increases, with the highest value of 7.91 mg/g for the solid obtained in the pyrolysis at 550 °C. In addition, adsorption capacity increases as the initial concentration of lead rises, reaching a maximum value close to 26 mg/g for an initial concentration of 40 mg/L. The Sips model is the one that best reproduces the experimental results of the adsorption process equilibrium study.

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