Carbon Black Samples Research Articles

Tuning the soft bandgap in the density of the states: The measurement of a "magnetogap" effect in carbon-black samples

We investigated the magnetic field dependence on the variable range hopping electron conduction in carbon-black samples with different volumetric densities. By applying the concepts and equations of hopping regimes when the magnetic field is applied, we were able to establish a connection between the variation of the hopping temperatures, TES and TM, with the localization radius of electron conduction in carbon-black, as well as with the density of states of this material. The volumetric density dependence of all these physical quantities is also discussed. Finally, based on the magnetic field effects on the hopping parameters, we introduced the idea of a "Magnetogap" effect, indicating how the Coulomb gap changes with the magnetic field.

Stretchable Conductive Inks with Carbon‐Based Fillers for Conformable Printed Electronics

With the constant increase of electronic waste globally, society is demanding and governments are boosting the development of electronics with less pollutant materials and reduced environmental impact. One way to achieve this is to implement materials that are functional and structural at the same time, reducing material use and assembling parts. Further, printing techniques, such as screen printing, reduce considerably costs and time compared with conventional electronics; combined with methods to conform printed electronics to a 3D shape, such as thermoforming, allow to obtain nonplanar surface electronics simply and efficiently. Herein, screen‐printable inks made of styrene–ethylene/butylene–styrene and different aspect‐ratio carbon‐based materials for conformable electronics are reported. The inks are prepared with carbon black, carbon nanotubes, and reduced graphene oxide as conductive fillers, printed on a flexible substrate and thermoformed. Carbon black and carbon nanotube samples are functional after the process, with conductivities of 96 and 141 S m−1 for the best performing sample of each filler, respectively. Rheological, morphological, thermal, and electrical properties of the materials are also characterized. This study shows the influence of the filler's type and aspect ratio on the morphology and electrical conductivity of the printed materials before and after thermoforming.

A HAZOP of dust explosion testing and explosibility modelling using artificial neural networks

AbstractThis work presents artificial neural network (ANN) models to determine explosion severity parameters (e.g., maximum explosion pressure and maximum rate of pressure rise) of given dust samples. ANN‐based models for explosibility parameters are presented for carbon black, zinc, urea, and oat grain flour dust samples based on data generated in a 20‐L explosion chamber. The optimal hyper‐parameters of the models have been explored using the Broyden–Fletcher–Goldfarb–Shanno, stochastic gradient descent, and Adam solvers. A hazard and operability study has also been conducted for each of the following to diagnose issues at different stages in developing the ANN‐based dust explosibility models: dust testing, model selection, parameter learning, and evaluation. Using different guidewords, the deviation of numerous factors from their design intent, causes, consequences, and specific safeguards have been provided for enabling optimal performance. This can be helpful in understanding, evaluating, and analyzing dust explosions for safer operation of industrial activities handling combustible dusts.

Factors Determining Black Carbon Exposures among Pregnant Women Enrolled in the HAPIN Trial.

Residential biomass burning is an important source of black carbon (BC) exposure among rural communities in low- and middle-income countries. We collected 7165 personal BC samples and individual/household level information from 3103 pregnant women enrolled in the Household Air Pollution Intervention Network trial. Women in the intervention arm received free liquefied petroleum gas stoves and fuel throughout pregnancy; women in the control arm continued the use of biomass stoves. Median (IQR) postintervention BC exposures were 9.6 μg/m3 (5.2-14.0) for controls and 2.8 μg/m3 (1.6-4.8) for the intervention group. Using mixed models, we characterized predictors of BC exposure and assessed how exposure contrasts differed between arms by select predictors. Primary stove type was the strongest predictor (R2 = 0.42); the models including kerosene use, kitchen location, education, occupation, or stove use hours also provided additional explanatory power from the base model adjusted only for the study site. Our full, trial-wide, model explained 48% of the variation in BC exposures. We found evidence that the BC exposure contrast between arms differed by study site, adherence to the assigned study stove, and whether the participant cooked. Our findings highlight factors that may be addressed before and during studies to implement more impactful cookstove intervention trials.

Study on the Evolution of Physicochemical Properties of Carbon Black at Different Regeneration Stages of Diesel Particulate Filters Regenerated by Non-Thermal Plasma

As a new type of aftertreatment technology, non-thermal plasma (NTP) can effectively decompose the particulate matter (PM) deposited in diesel particulate filters (DPFs). In this paper, a regeneration test of a DPF loaded with carbon black was carried out using an NTP injection system, and the changes of oxidative activity, elemental content, and occurrence state, microstructure and graphitization degree of carbon black were analyzed to reveal the evolution of the physicochemical properties of carbon black at different regeneration stages of the DPF regenerated by NTP. As the regeneration stage of the DPF advanced, Ti, Tmax, and Te of the carbon black at the bottom of the DPF decreased, which were higher than those at the regeneration interface. After the NTP reaction, the proportion of C element decreased to less than 80%, while the proportion of O element increased to more than 20%; C-O was converted to C=O and the relative content of C=O increased. The average microcrystalline length and average spacing decreased, while the average microcrystalline curvature increased. The ID1/IG (relative peak intensities) of carbon black samples decreased from 3.31 to 3.10, and the R3 (relative peak intensities, R3 = ID3/(IG + ID2 + ID3)) increased from 0.41 to 0.58. The content of carbon clusters had a great influence on the disorder of the microcrystalline structure, so the graphitization degree of carbon black decreased and the oxidation activity increased.

Effect of graphene oxide and carbon black on the thermoelectric performance of niobium doped strontium titanate

Strontium titanate-based ceramics are promising n-type thermoelectrics due to their low cost and high thermal and chemical stability. Here, SrTi0.85Nb0.15O3 was prepared with carbon additions of electrochemically produced graphene oxide (eGO) and commercially available carbon black (CB). Ceramic samples were sintered at 1700 K under a reducing atmosphere. XRD, HR-TEM and Raman spectra confirmed the matrix phase was cubic perovskite; there were no carbon residues. By incorporating graphene oxide, the electrical conductivity increased nine-fold to 2818 S cm−1 at 300 K as a result of enhanced carrier mobility. In contrast, the carbon black samples exhibited low density and a small average grain size of ∼1 μm. High-resolution X-ray photoelectron spectroscopy revealed the presence of a large number of ionised impurities in the carbon black samples, which significantly enhanced scattering effects; low thermal conductivities of 1.7 W m−1 K−1 were achieved at 873 K. The work reveals that eGO promotes charge transport in SrTiO3, while CB significantly suppresses phonon transport. Both effects are relevant to the development of other thermoelectrics.

The effect of carbon black percentage on mechanical properties and microstructure of polybutylene terephthalate/polyamide 6/carbon black blends

This study focuses on analyzing the influence of carbon black (CB) on Polybutylene terephthalate (PBT)/Polyamide 6 (PA6) blends. This study aims to solve the source of waste from toothbrush filament during production. This PBT/PA6 mixture does not meet the mechanical properties due to the incompatibility of these two plastics, which means this waste must be discarded and cannot be reused. When combined with CB, it creates a new type of plastic with more stable mechanical properties that can be applied in many areas of life and, at the same time, helps manufacturing businesses save on waste treatment costs. To create these PBT/PA6/CB blends, the research team used injection molding with a PBT/PA6 ratio of 75/25 combined with 0, 4, 8, and 12 % carbon black. The tensile and impact strength were tested according to the ASTM D638 and ASTM D256 standards. The results found that when adding 4 % CB to the PBT/PA6 plastic mixture, the tensile strength decreased from 34.9 to 34.8 MPa. Meanwhile, the tensile strength is improved when adding 8 % CB (35.3 MPa). At 12 % CB, a difference in tensile strength results, decreasing to 29.7 MPa. This result shows that the ratio 75/25 can give the best tensile strength value of the PBT/PA6 mixture with 8 wt. % CB. The impact strength was 3.5, 2.9, and 2.7 kJ/m2 according to 4, 8, and 12 % CB samples. Mechanical quality tests have shown that the tensile strength is improved when combining CB into the PBT/PA6 mixture, but the impact strength is reduced. SEM results show that most CB interacts with PBT/PA6 mainly because the PA6 particles are spherical and tend to separate easily from the mixture. The research found that increasing CB density worsens the bonding ability between PBT and PA6. These results help us provide experience for the most appropriate application for each purpose

Novel olive stone biochar particle network for piezoresistive strain sensing in natural fiber‐reinforced composites

AbstractNatural fiber‐reinforced composites (NFRCs) suffer from water absorption and low temperature stability, resulting in fiber degradation and subsequent material failure. Built‐in piezoresistive sensors are investigated to monitor the deformation/strain of the component. As a low‐cost material from renewable resources biochar particles derived from olive stones were applied on flax plies and yarn bundles that served as model systems. Carbon black samples as petrochemical variants were used as a reference material. Biochar and carbon black‐covered fiber systems were laminated in epoxy resin followed by tensile tests. The electrical resistance was recorded simultaneously during testing. Biochar with a broad size distribution from nano to high micrometer range (D < 200 μm) was superior in sensor performance compared to carbon black and biochar with a smaller particle size range D < 20 μm. Gauge factors (GF) of NFRC samples with integrated biochar particles reached 30–80 while carbon black could not exceed a GF of 8. To obtain maximum GFs, yarn count of flax yarn/ply substrate should be as thin as possible, but still enable percolation of the adhering particle network. Comparatively large particle size was identified as a contributing factor enabling the high GF for coarse biochar compared to carbon black.Highlights A nonfossil biochar built‐in piezoresistive sensor in natural fiber‐reinforced composites was fabricated Deposing biochar directly on flax fibers facilitates processing The biochar piezoresistive sensor exhibits superior sensitivity compared to carbon black

Activation of biomass precursors and chemical preparation of hierarchical porous carbons for supercapacitor applications

Growing population in the world demands more accumulation of energy. Among the storage devices, capacitors have triggered enormous interest due to its excellent electrochemical characteristics. Activated carbon electrodes from Africana Duranta, Tectona Grandis, and Terminalia Catappa carbon waste, have attracted high interest because of high specific surface area and an abundant pore volume with rational micro/meso pores. The carbon black samples were prepared by a simple green synthesis with KOH treatment followed by pyrolysis method. XRD confirmed the amorphous carbon black allotrope of the carbon black respectively. The carbon obtained from the leaf, Africana Duranta showed high surface area in the range of 9.08 m²/g - 28.592 m²/g with pore radius in the range of 16.768 Å – 877.4509 Å, which was found from BJH and BET analysis respectively. Then the specific capacitance values were calculated from the CV curves using electrochemical analyzer. The highest specific capacitance value of 83.58 Fg-1 was found for Africana Duranta, which was mainly due to high surface area compared to other two leaves.

Analyzing the Effect of Nano-Sized Conductive Additive Content on Cathode Electrode Performance in Sulfide All-Solid-State Lithium-Ion Batteries

All-solid-state lithium-ion batteries (ASSLBs) have recently received significant attention due to their exceptional energy/power densities, inherent safety, and long-term electrochemical stability. However, to achieve energy- and power-dense ASSLBs, the cathode composite electrodes require optimum ionic and electrical pathways and hence the development of electrode designs that facilitate such requirements is necessary. Among the various available conductive materials, carbon black (CB) is typically considered as a suitable carbon additive for enhancing electrode conductivity due to its affordable price and electrical-network-enhancing properties. In this study, we examined the effect of different weight percentages (wt%) of nano-sized CB as a conductive additive within a cathode composite made up of Ni-rich cathode material (LiNi0.8Co0.1Mn0.1O2) and solid electrolyte (Li6PS5Cl). Composites including 3 wt%, 5 wt%, and 7 wt% CB were produced, achieving capacity retentions of 66.1%, 65.4%, and 44.6% over 50 cycles at 0.5 C. Despite an increase in electrical conductivity of the 7 wt% CB sample, a significantly lower capacity retention was observed. This was attributed to the increased resistance at the solid electrolyte/cathode material interface, resulting from the presence of excessive CB. This study confirms that an excessive amount of nano-sized conductive material can affect the interfacial resistance between the solid electrolyte and the cathode active material, which is ultimately more important to the electrochemical performance than the electrical pathways.

Investigation of a 2D Metallic Selenide for Supercapacitative Applications

The study investigates the suitability of a 2D metallic selenide material for use in supercapacitors, which are rapidly gaining recognition as a viable energy storage solution. While supercapacitors are highly efficient at charging and discharging, their lower energy density is a limiting factor. This research focuses on identifying new materials that can enhance the energy density of supercapacitors while maintaining their rapid charging capabilities. The study examines CrSe2, a promising chalcogenide material that has recently been suggested for use in hybrid composite systems. The research shows that CrSe2 can be made in bulk quantities and exhibits high stability in certain electrolytes. The electrochemical properties of CrSe2 are measured for the first time and found to be consistent with an electric double-layer capacitance. Additionally, the material demonstrates a high specific capacitance, indicating potential for use in supercapacitive applications. The study concludes that the metallic-type conductivity of CrSe2 could be responsible for its superior performance over high surface area carbon black samples.

A comprehensive study on effect of carbon nanomaterials as conductive additives in EDLCs

This study performs a comprehensive investigation to objectively analyze the effects of various carbon nanomaterials using as conductive additives (5 wt%) in activated carbon (AC) based electrodes for electrical double-layer capacitors (EDLCs). A variety of carbon nanomaterials including carbon black (CB), single-walled carbon nanotubes (SWCNT), graphene nanoplatelets (GNP), fullerenes (C60), and activated carbon nanofibers (ACNF) are considered in this work as they provide a diverse combination of intrinsic properties such as specific surface area, conductivity, micro-mesoporous structures, and geometry of nanomaterials. These additives are incorporated into freestanding carbon electrodes, and their EDLC performance in a neutral aqueous electrolyte is investigated by means of electrochemical measurements. The findings from this work provide useful insight into how the properties of various carbon nanomaterials influence EDLC performance in different aspects such as capacitive behavior, resistivity, performance at different current densities, charge propagation properties, and stability over long-term cycling. The results show that each carbon additive has its own strengths and limitations for different performance parameters considered. The unfavorable material properties of C60 cause a significant decrease in capacitance at high current density, leading to the lowest device performance incorporated with C60 as additives. While GNP and SWCNT show high crystallinity, low ID/IG ratios, the EDLCs still exhibit decreased specific capacitance and moderate energy densities due to their relatively limited specific surface area and high resistivity of the resultant composite electrodes compared to the pristine AC. The CB additives-based samples demonstrate the highest conductivity of dry electrodes and low equivalent series resistance (ESR) in EDLCs. On the other hand, a reduction in capacitance at high current densities and material degradation during long-term cycling are observed for CB samples, which could be attributed to the high dispersibility of CB causing limited interparticle voids and thus increasing diffusion resistance. In contrast, the use of ACNFs significantly reduces the diffusion resistance and improves the cyclic stability compared with CB based samples due to the advantages of larger specific surface area and superior micro-mesoporous structures of ACNFs. In particular, EDLCs with ACNFs demonstrate an increase in specific capacitance and energy density by 99 % and 76 %, respectively compared to CB based EDLCs at a current density of 20 A/g. This work elucidates the complex interplay between carbon nanomaterials using as additives and corresponding EDLC performance. These results provide important information to the community for future development of new energy conversion and storage devices.

Thermal and Surface Area Properties of Micro and Nano Sized Pumice

Raw pumice samples were modified with nano carbon black, borax, and nano carbon-borax using the sol-gel method by applying surface modification processes, and the changes in the thermal behavior of the surface modification of the raw pumice were studied by characterizing them with FE-SEM, EDX, FT-IR, XRD, BET and TGA-DTA. In the analyses made with FE-SEM, it was observed that the surface and pore structure of the raw pumice changed after the modified process, and in the EDX analysis, it was determined that nano carbon black and borax adhered to the surface of the raw pumice. In the XRD results, no change in the crystal structure of the raw pumice was observed after the modified treatment. TGA-DTA analysis showed that the mass loss of raw pumice (P) was greater than pumice-nano carbon black (PC), pumice-borax (PB), and pumice-borax-nano carbon black (PBC). Accordingly, raw pumice showed a mass loss of approximately 25%, pumice-borax (PB) and pumice-nano carbon black (PC) 0.45%, and pumice-borax-nano carbon black (PBC) nearly 3%. According to the BET analysis results, it was determined that the raw pumice has a surface area of 28.126 m2/g. After the surface modification process, the surface area of the raw pumice was determined as 52.127 m2/g in the pumice-nano carbon black sample, 49.125 m2/g in the pumice-borax sample, and 32.523 m2/g in the pumice-borax-carbon black sample. Considering the data obtained, the best surface properties were showed in pumice-nano carbon black (PC). Research results showed that; the modification process with nano carbon black and borax changed the thermal behavior of raw pumice.

Evolution of the Viscoelastic Properties of Filler Reinforced Rubber under Physical Aging at Room Temperature.

Filler reinforced rubber is widely used for engineering applications; therefore, a sound characterization of the effects of physical aging is crucial for accurately predicting its viscoelastic properties within its operational temperature range. Here, the torsion pendulum is used to monitor the evolution of the storage and loss modulus of carbon black filled samples for four days after a temperature drop to 30 °C. The storage modulus presents a continuous increase, while the loss modulus generally displays a steady decrease throughout the four days that each test was conducted. The relationship of the recovery rates with the carbon black properties is also studied, analysing its dependency on the particle size and aggregate structure. The evolution of the recovery rate seems to depend linearly on the surface area while the carbon black structure appears to have a much weaker influence on the physical aging behavior for the set of compounds tested. The obtained results corroborate the presence of physical aging at room temperature for filler rubber materials and the ability of the torsion pendulum to monitor the storage and loss modulus change, providing pivotal data on the influence of physical aging on the viscoelastic properties of the material.

Quantitative Analysis of the Cu Element Enhanced by AgNPs in a Single Microsized Suspended Particle Based on Optical Trapping-LIBS and Machine Learning.

Extremely severe and persistent particulate pollution caused by industrialization and urbanization impacts air quality, regional and global climates, and human health. The unstable and complex spectral signal of laser-induced breakdown spectroscopy (LIBS) with minimal feature information and interference signals considerably influences the accuracy of qualitative and quantitative analysis. In response to overcome this phenomenon, in this work, quantitative analysis of Cu element enhanced by silver nanoparticles (AgNPs) in a single microsized suspended particle was proposed herein using optical trapping-LIBS and machine learning method was proposed. Initially, the optimal AgNPs enhancement conditions were optimized. The LIBS spectra of 15 polluted black carbon samples were collected and various spectral pretreatment methods were compared to optimize the LIBS spectra. Variable selection methods include variable importance measurement (VIM), variable importance projection (VIP), VIM-successive projections algorithm (VIM-SPA), VIM-genetic algorithm (VIM-GA), and VIM-mutual information (VIM-MI). Finally, several hybrid variable selection methods were implemented in random forest (RF) calibration models. In particular, a wavelet transform (WT)-VIM-SPA-RF calibration model has constructed under the WT spectral pretreatment method and the selected and optimized input variables (VIM-SPA). Results elucidate that the WT-VIM-SPA-RF calibration model (R2P = 0.9858, MREP = 0.0396) have the best prediction performance than the WT-RF and Raw-RF models in predicting the Cu level in a single microsized black carbon particle. Compared to the WT-RF and Raw-RF models, MREP values decreased by 37% and 62%, respectively. The values of RSD, RPD, and RER of this calibration model are 2.8%, 8.39%, and 17.79%, respectively. The aforementioned results demonstrate that the WT-VIM-SPA-RF calibration model with accuracy, stability, and robustness is a promising approach for improving the quantitative accuracy of the Cu level in carbon black particles.

Carbon Black Doped Graphite Composite Bipolar Plate Compounds for Improving Conductivity

Bipolar plates are a key part of fuel cells. The optimal hot press temperature, pressure, and time were determined in this study. The press condition can directly affect the relative density, thereby improving the conductivity and mechanical property. Several carbon black doped samples were also successfully prepared on the basis of the optimized preparation method. Results show that carbon black optimized the conductivity due to the “conduction bridge”. The maximum conductivity and bending strength reached 345 S/cm and 32.5 MPa, respectively. Key words: fuel cells; bipolar plate; graphite; composite materials.

Investigation of Amorphous Carbon in Nanostructured Carbon Materials (A Comparative Study by TEM, XPS, Raman Spectroscopy and XRD).

Amorphous carbon (AC) is present in the bulk and on the surface of nanostructured carbon materials (NCMs) and exerts a significant effect on the physical, chemical and mechanical properties of NCMs. Thus, the determination of AC in NCMs is extremely important for controlling the properties of a wide range of materials. In this work, a comparative study of the effect of heat treatment on the structure and content of amorphous carbon in deposited AC film, nanodiamonds, carbon black and multiwalled carbon nanotube samples was carried out by TEM, XPS, XRD and Raman spectroscopy. It has been established that the use of the 7-peak model for fitting the Raman spectra makes it possible not only to isolate the contribution of the modes of amorphous carbon but also to improve the accuracy of fitting the fundamental G and D2 (D) modes and obtain a satisfactory convergence between XPS and Raman spectroscopy. The use of this model for fitting the Raman spectra of deposited AC film, ND, CB and MWCNT films demonstrated its validity and effectiveness for investigating the amorphous carbon in various carbon systems and its applicability in comparative studies of other NCMs.

Effect of Alumina Modified by Silane on the Mechanical, Swelling and Dielectric Properties of Al2O3/EPDM/SBR Blend Composites

Rubber blending has been widely used to improve various properties in finished rubber products. The purpose of this paper is to investigate the effect of filler size, type, concentration, and surface treatment on the mechanical, swelling, dielectric, and morphology properties of ethylene propylene diene rubber (EPDM)/styrene-butadiene rubber (SBR) rubber blend nanocomposites filled with alumina (Al2O3) nanoparticles. Bis-(3-(triethoxysilyl)-propyl)-tetrasulfide (TESPT) was used as a silane coupling agent. Rubber blend nanocomposites containing Al2O3 nanoparticles were compared to carbon black (CB). The results indicate that the nanocomposites prepared, in particular with the TESPT, had better properties than the composites without the TESPT. Mechanical properties of the CB-filled EPDM/SBR rubber blend were noticeably improved, indicating CB's inherent reinforcing potential. We found that rubber nanocomposites' crosslink density and filler–rubber interaction increase, and the swelling coefficient decreases with increasing filler content. The dielectric properties of the nanocomposites showed a significant enhancement with fillers. SEM images showed that the CB sample had a higher distribution than Al2O3 due to good interaction and dispersion. This study's experimental data will help design and manufacture outdoor insulators.

Multi-element Quantitative Analysis of Single Micro-sized Suspended Particles in Air with High Accuracy Based on Random Forest and Variable Selection Strategies.

The chemical compositions of atmospheric particles have been studied for several decades, and the traditional techniques for particle analysis usually require time-consuming sample preparation. Within this study, simultaneous quantitative detection of multiple metallic species (Zn, Cu, and Ni) in single micro-sized suspended particles was investigated by combining random forest (RF) and variable selection strategies. Laser-induced breakdown spectra of 15 polluted black carbon samples were applied for establishing the RF model, and the movmean smoothing spectral pretreatment method and variable selection methods [variable importance measurement (VIM), genetic algorithm (GA), and variable importance projection (VIP)] were proposed. Finally, the optimized RF calibration model with the evaluation indicators of mean relative error (MRE), root-mean-square error (RMSE), and coefficient of determination (R2) was constructed based on the optimal input variables and model parameters. Compared with the univariate regression method, the VIP-RF (Zn) and VIM-RF (Cu and Ni) models showed a better correlation relationship (Rp2 = 0.9662 for Zn, Rp2 = 0.9596 for Cu, and Rp2 = 0.9548 for Ni). For Zn, Cu, and Ni, the values of RMSEP (RMSE of prediction) decreased by 116.44, 68.94, and 102.10 ppm, while the values of MREP (MRE of prediction) decreased by 67, 55, and 48%, respectively. The values of ratio of prediction to deviation (RPD) of VIP-RF (Zn), VIM-RF (Cu), and VIM-RF (Ni) models were 5.4, 5.0, and 4.7, respectively. The performance of this combined approach displays a notable accuracy improvement in the quantitative analysis of single particles, suggesting that it is a promising tool for real-time air particulate matter pollution monitoring and control in the future.

Adsorption of 2,4-D and MCPA Herbicides on Carbon Black Modified with Hydrogen Peroxide and Aminopropyltriethoxysilane.

The carbon black N-220 surface was subjected to modification through H2O2 oxidation and deposition of aminopropyltriethoxysilane. The pristine (CB-NM) and modified materials (CB-Ox and CB-APTES) were characterized by N2 adsorption−desorption isotherms, scanning electron microscopy, energy-dispersive X-ray spectroscopy (SEM-EDS), thermogravimetry, and FTIR spectroscopy. Carbon black samples were applied as adsorbents for the removal of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chlorophenoxyacetic acid (MCPA) herbicides from aqueous solutions. The influence of their surface properties on adsorption efficiency was analyzed and discussed. The results showed that the adsorption of the herbicides was pH-dependent, and the most favorable adsorption was observed in an acidic environment. The experimental data best fit pseudo-second-order and Langmuir models for kinetic and equilibrium data, respectively. The adsorption rate of both the herbicides increased in the order of CB-APTES < CB-Ox < CB-NM and was closely correlated with the mesopore volume of the carbon blacks. The monolayer adsorption capacities were found to be 0.138, 0.340, and 0.124 mmol/g for the adsorption of 2,4-D and 0.181, 0.348, and 0.139 mmol/g for the adsorption of MCPA on CB-NM, CB-APTES, and CB-Ox, respectively. The results showed that the surface chemistry of the adsorbent plays a more important role than its porous structure. Both herbicides were preferably adsorbed on APTES-modified carbon black and were adsorbed the worst on oxidized carbon black (CB-APTES > CB-NM > CB-Ox).