Modification Of Functional Groups Research Articles

Insight into the effect of OH modification on the piezo-photocatalytic hydrogen production activity of SrTiO3

Surface modification by hydrophilic functional group have a tremendous influence on the catalytic activity of photocatalyst, however, there are few reports on improving piezoelectric catalytic performance through surface functionalization. Herein, OH-modified SrTiO3 was successfully obtained via a novel low-temperature solid-state precursor method and employed as a catalyst for photocatalytic, piezocatalytic and piezo-photocatalytic hydrogen production. Thanks to the super hydrophilic that is facilitating the contact of catalyst and water molecular and the more oxygen vacancies that can promote electron-hole separation, the photocatalytic, piezocatalytic and piezo-photocatalytic hydrogen generation of OH-modified SrTiO3 (OH-STO) is about two times higher than pristine SrTiO3 (STO). It is worth mentioning that the optimal piezo-photocatalytic hydrogen evolution rate of OH-STO (701.2 µmol h−1 g−1) is 5.3 times higher than the photocatalytic hydrogen evolution process of STO. This study presents a low-energy approach to the rational design of functional group modification nanomaterials that possess excellent piezo-photocatalytic performance.

Design, Synthesis and Biological Investigation of Some Novel Quinazolin-4(3H)-One Tethered 1, 3, 4-Thiadiazole-Thiol Motifs as Direct Enoyl Acyl Carrier Protein Reductase Inhibitors

Aims: In this study was two noteworthy pharmacophores quinazolin-4(3H)-one and 1,3,4-thiadiazole through methylene bridge were utilized to design, synthesize and characterize some novel 2-methyl quinazolin-4(3H)-one and 6-chloro-2-methyl quinazolin-4(3H)-one tethered S-substituted-1,3,4-thiadiazole-thiol structural analogs respectively as direct Mycobacterium Tuberculosis (MTB) enoyl acyl carrier protein reductase (InhA) inhibitors.
 Study Design: Design of structural analogs of quinazolin-4(3H)-one tethered 1,3,4-thiadiazole-thiol through methylene bridge by functional group modifications in core scaffold followed by computational studies to select promising compounds. Synthesis of some novel compounds, structural characterization and screening of biological activity of the same.
 Methodology: The molecular docking of designed compunds was carried out using schrodinger Glide XP into the active site of MTB InhA with protein data bank code (PDB ID: 2H7M). The interactions were evaluated based on the glide G score compared with reference standard isoniazid. Ten new compounds 7(A1-A10) were synthesized, characterized and screened for their in-vitro antitubercular activity by Microplate Almar Blue Assay (MABA) method followed by cytotoxicity evaluation of compounds 7A4 and 7A10 using Vero cell line.
 Results: All the designed compounds of series 7(A1-A10) had drug-like characteristics and were non-toxic to normal cells. In the molecular docking studies, compounds 7A4, 7A5, and 7A10 demonstrated strong binding affinity in the active region of MTB InhA protein and retained necessary amino acid interaction, similar to co-crystal 2H7M. Synthesized compounds 7(A1-A10) were found to have good antitubercular activity. Out of the series the compounds 7A4 and 7A10 were found to possess excellent antitubercular activity equipotent to reference standard streptomycin with minimum inhibitory concentration (MIC) value of 6.25µg/ml. The cytotoxic potential of compounds 7A4 and 7A10 showed remarkable selectivity index against Vero cell line.
 Conclusion: The findings of this study highlights the importance of tethering two pharmacophoric motifs in one compound to develop novel antitubercular agents that can be exploited as promising leads as direct InhA inhibitors.

Valorisation of wheat straw and bioethanol production by a novel xylanase- and cellulase-producing Streptomyces strain isolated from the wood-feeding termite, Microcerotermes species

Lignocellulosic biomass represents an unlimited and ubiquitous energy source, effectively addressing current global energy demand challenges. However, the recalcitrant nature of lignocellulose hinders microbial degradation, necessitating an appropriate hydrolytic enzyme production source for biomass valorisation and bioethanol production. This study might be the first to explore a novel bacterial species Streptomyces sp. strain MS-S2, isolated from the higher wood-feeding termite, Microcerotermes sp.; capable of concurrent degradation and saccharification of wheat straw for the liberation of reducing sugars, which can further be converted to bioethanol. The Streptomyces sp. MS-S2 demonstrated the capacity to efficiently utilise wheat straw as the sole carbon source for the secretion of xylanase and cellulase enzymes. The highest cellulase and xylanase productions were observed for ten days when the bacterium was cultured in the medium amended with 15 g/L of wheat straw and 1.5% yeast extract at pH 8.0, 30 ℃. Under optimum conditions, xylanase and cellulase activities were estimated to be 6.560 ± 0.160 and 0.866 ± 0.067 U/mL, respectively. Through Scanning electron microscopy analysis, the surface accessibility of cellulose fibrils in treated wheat straw was observed, indicating the efficiency of the hydrolysis process. In addition, functional group modifications from Fourier transform infrared spectroscopy analysis demonstrated the successful depolymerisation of wheat straw. Further, excreted enzymes produced under optimal conditions were applied to wheat straw hydrolysis for the liberation of reducing sugars. Then, ethanol production was obtained at a maximum concentration of 10.8 g/L. The findings of this study could open a new path for the search of new lignocellulolytic-producing bacteria inhabiting the gut symbionts of wood-feeding termites to valorise lignocellulosic biomass into biotechnologically value-added products such as biofuels.

Visible-Light-Mediated Modification and Manipulation of Biomacromolecules.

Chemically modified biomacromolecules─i.e., proteins, nucleic acids, glycans, and lipids─have become crucial tools in chemical biology. They are extensively used not only to elucidate cellular processes but also in industrial applications, particularly in the context of biopharmaceuticals. In order to enable maximum scope for optimization, it is pivotal to have a diverse array of biomacromolecule modification methods at one's disposal. Chemistry has driven many significant advances in this area, and especially recently, numerous novel visible-light-induced photochemical approaches have emerged. In these reactions, light serves as an external source of energy, enabling access to highly reactive intermediates under exceedingly mild conditions and with exquisite spatiotemporal control. While UV-induced transformations on biomacromolecules date back decades, visible light has the unmistakable advantage of being considerably more biocompatible, and a spectrum of visible-light-driven methods is now available, chiefly for proteins and nucleic acids. This review will discuss modifications of native functional groups (FGs), including functionalization, labeling, and cross-linking techniques as well as the utility of oxidative degradation mediated by photochemically generated reactive oxygen species. Furthermore, transformations at non-native, bioorthogonal FGs on biomacromolecules will be addressed, including photoclick chemistry and DNA-encoded library synthesis as well as methods that allow manipulation of the activity of a biomacromolecule.

THE ROLE OF N-DOPING TO THE PORE CHARACTERISTICS OF ACTIVATED CARBON FROM VETIVER ROOT DISTILLATION WASTE

This work studied the effect of nitrogen functional group modification on activated carbon synthesized from vetiver root waste on pores development. Synthesis of activated carbon was carried out by hydrothermal carbonization of vetiver root waste at a temperature of 225 ⁰C for 18 hours followed by chemical activation using K2FeO4as activated agent in a furnace at temperature of 800 ⁰C for 2 hours with nitrogen atmosphere flowed at a rate of 100 mL/minute. Urea was used as a nitrogen source. The variation of urea concentration was 1:0 (AC0–800), 1:3 (AC3–800) and 1:5 (AC5–800). The results showed that these activated carbons have mesoporous characteristics with the largest Brunauer Emmett Teller (SBET) surface area of 552.90 m2g-1 and average pore width 3,43 nm. The presence of nitrogen functional group was observed in the Fourier Transform Infrared Spectrometer analysis. Synthesis of activated carbon from vetiver root waste with an addition of urea is the newest method to produce mesoporous activated carbon for electrode and support catalyst purposes.

Removal of Hydrogen Peroxide Residuals and By-Product Bromate from Advanced Oxidation Processes by Granular Activated Carbon

During drinking water treatment, advanced oxidation process (AOP) with O3 and H2O2 may result in by-products, residual H2O2 and BrO3−. The water containing H2O2 and BrO3− often flows into subsequent granular activated carbon (GAC) filters. A concentrated H2O2 solution can be used as GAC modification reagent at 60 °C to improve its adsorption ability. However, whether low concentrations of H2O2 residuals from AOP can modify GAC, and the impact of H2O2 residuals on BrO3− removal by the subsequent GAC filter at ambient temperature, is unknown. This study evaluated the modification of GAC surface functional groups by residual H2O2 and its effect on BrO3− removal by GAC. Results showed that both H2O2 and BrO3− were effectively removed by virgin GAC, while pre-loaded and regenerated GACs removed H2O2 but not BrO3− anymore. At the ambient temperature 150 µmol/L H2O2 residuals consumed large amounts of functional groups, which resulted in the decrease of BrO3− removal by virgin GAC in the presence of H2O2 residuals. Redox reactions between BrO3− and surface functional groups played a dominant role in BrO3− removal by GAC, and only a small amount of BrO3− was removed by GAC adsorption. The higher the pH, the less BrO3− removal and the more H2O2 removal was observed.

Mercury Adsorption on Thiol-Modified Porous Boron Nitride: A Combined Experimental and Theoretical Investigation

Heavy metal pollutants from industrial wastewater pose a great threat to public health and ecosystem safety. In this paper, a thiol-modified porous boron nitride (pBN–SH) adsorbent synthesized by a facile acid-etching method was studied for the highly selective adsorption of Hg(II) in a complex environment. pBN–SH was characterized by X-ray diffraction, thermogravimetric, elemental analysis, Brunauer–Emmett–Teller analysis, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared, and X-ray photoelectron spectroscopy. The effect of adsorption dosage, pH, contact time, and temperature on Hg(II) adsorption was comprehensively investigated. Characterized results show that thiol groups are loaded on the surface of pBN through oxygen-containing groups and π–π bond. Due to the abundant structural defects and surface modification of functional groups, pBN–SH can effectively capture Hg(II) from water. Compared with the pristine pBN, the adsorption capacity of pBN–SH increases significantly by nearly 2.1 times, which suggests broad application prospects of pBN–SH in removing the Hg(II) aspect. Experimental results corresponding to the pseudo-second-order kinetic, the intra-particle diffusion model, and the Langmuir isotherm demonstrate that pBN–SH holds a high potential in environmental remediation. In addition, the recovered pBN–SH loaded with Hg(II) waste can be available for a valid catalyst for the conversion of phenylacetylene to acetophenone, providing a new way for the reuse of Hg(II)-adsorbed materials. Density functional theory calculations revealed that multitudinous defects and thiol functional groups on the pBN–SH surface, electrostatic attraction, and ligand exchange are responsible for the excellent Hg(II)-selective adsorption capability discovered in the experiment.

Novel Antitubercular Derivatives of Mannich and Schiff Bases of p-Aminosalicylic Acid – Rational Design

Aims: The aim of the current study is to utilize computational drug design resources to develop and identify promising structural analogs of p-aminosalicylic acid (PAS), to improvise antitubercular activity followed by their synthesis, characterization, and in-vitro biological activity determination.
 Study Design: Design of the structural analogs of PAS by functional group modification at -COOH and -NH2 groups followed by in-silico prediction of biological activity, toxicity, drug-likeness filters, and molecular docking study to select promising analogs. Synthesis of selected analogs, structural characterization, and screening of biological activity of the same.
 Methodology: Using the Prediction of Activity Spectrum of Substances (PASS Online) database, prediction of biological activity was performed for PAS and 22 designed structural analogs of PAS. All these analogs were screened for their drug-likeness properties using Lipinski’s rule of five. Later all these 22 analogs were predicted for their toxicities using OSIRIS Property Explorer. At this stage, out of 22 analogs, only 6 analogs were selected to go for molecular docking using AutoDock Tools and AutoDock Vina for the determination of their binding energies by comparing with PAS. The selected 6 analogs were synthesized using three-step syntheses. The synthesized analogs were screened for their antitubercular activity using the Microplate Alamar Blue Assay (MABA) method.
 Results: Overall 22 structural analogs were designed and screened for their estimated activity (all analogs showed antitubercular activity as primary activity), drug-likeness (all analogs passed), and toxicities (only 10 analogs passed) using computational tools. Out of 22 analogs, 6 analogs were selected and performed molecular docking using AutoDock Vina. All 6 analogs showed better binding affinity than PAS. These 6 analogs (7a-f) were synthesized, characterized, and screened for their in-vitro antitubercular activity. Results showed that 5 analogs, 7b-7f, showed excellent antitubercular potency greater than PAS and equipotent activity to that of standard drugs. Analog 7a was found to be less potent than PAS.
 Conclusion: Hence, the structural analogs of PAS, 7b-7f, were found to have better antitubercular activity than the lead compound, PAS, and equipotent to that of the standards, streptomycin, ciprofloxacin, and pyrazinamide.

Towards a more efficient Hydrothermal Carbonization: Processing water recirculation under different conditions.

The use of Processing Water (PW) on the Hydrothermal Carbonization (HTC) of tunisian pine cones was investigated under different temperature (200 and 240°C) and residence time conditions (3 and 20h). Recirculating PW improved the HC (hydrochar) solid yield, without being detrimental to the carbon content of the HC. The heating value of the HCs, that with a single reaction already involved a rise of this parameter in the range 22.1-55.8% as compared to the raw material, was further increased up to 24.9-58.6% for cyclic runs. This was attributed to enhanced secondary char formation by reusing liquid, although this effect depended on the severity of previous HTC and was affected by both temperature and time. The HCs showed an increment on C and especially on N for cyclic runs. Also, thermal degradation peaks during HC TGA/DTA analyses showed a broader temperature range decomposition upon pyrolysis when PW was recirculated. The modifications of HC surface morphologies and functional groups was also investigated and associated to related reaction mechanisms.

Natural and synthetic functional materials for broad spectrum applications in antimicrobials, antivirals and cosmetics

AbstractAntimicrobial resistance is the leading cause of burden on healthcare sector. There is scientific challenge of developing new functional material as a platform to prevent and treat viral and microbial infection and cosmetic utility. In material chemistry, there is progress in the development of functional material with advent of nanotechnology with aid of synthetic organic chemistry. The properties and application of material can be changed significantly by modification of the surface functional groups (namely, COOH, HO, NH2OH, SO4,), formation of composite with inorganic material and incorporation of active pharmaceutical agents. In antibacterial application functional material of copper, silver, gold, platinum, tin, iron, cobalt, ruthenium, zinc and pharmaceutical antimicrobial agents found utility in the treatment of bacterial and hospital acquired infection with different resistant strains of microorganisms. In antiviral application many functional materials have been shown to possess remarkable antiviral ability like quantum dots, gold and silver nanoparticles, nanoclusters, carbon dots, graphene oxide and silicon materials. The polymers and dendrimers functionalized with USFDA approved antiviral agent also has potential therapeutic outcomes. Despite their difference in antiviral mechanism and inhibition efficacy, these functional material structures have unique features as potential antiviral candidates. In cosmetic applications functional material based on mica, sericite, fullerene, charcoal, peptides, mineral, lipids, glucocorticoid, nanocellulose hybrid material are extensively used. In this review, we have highlighted early promise and prospects of functional material for cosmetics, antibacterial and antiviral applications, advantages and disadvantages, Patent scenario, current challenges for translation into commercial products.

Ultrasound pretreated rice bran for Rhizopus sp. phytase production as a feed

Phytasae enzymes have a major role in animal feed applications as they help in the bioavailability of phosphorus present in phytic acid, an anti-nutritional compound associated with higher plant proteins. However, achieving higher levels of phytase production and phytic acid degradation is still difficult in solid state fermentation (SSF). This study involved a comparison of ultrasonication treated and untreated rice bran (RB) to improve the phytase production using Rhizopus sp. Ultrasound treatment of rice bran has been optimized with different parameters such as ultrasound time, ultrasound cycle (UC), ultrasound amplitude and liquid to solid ratio (LSR). With optimal conditions of treated RB (40 min ultrasound time, 100% ultrasound cycle (no intervals during ultrasound), 40:10 (mL/g) LSR and 80% ultrasound amplitude), a 9.3-fold increase in phytase production was observed. Different analytical methods were used to study the characteristics of treated and untreated RB such as scanning electron microscope (SEM) for morphological changes, functional group modifications using Fourier transform infrared spectroscopy (FTIR), elemental composition using energy dispersive analysis of X-rays and the crystalline nature using X-ray diffraction (XRD). With optimized conditions, phytase production was carried out and its potential activity with simulated gastric fluids were studied at pH 2.0–5.0. The thermostability of the phytase enzyme was further improved by the addition of polyvinylpyrrolidone (PVP). Thus, the ultrasound treated RB can be a potential substrate for the efficient production of phytase and as a source for a nutritive supplement that might be used in the food and feed industries.

The Effect of Temperature, Sulfonation, and PEG Addition on Physicochemical Characteristics of PVDF Membranes and Its Application on Hemodialysis Membrane

Polyvinylidene fluoride (PVDF) membrane and its derivative have been investigated the permeation ability for creatinine and urea. The membrane was made by an inversion precipitation system in N,N-dimethyl acetamide (DMAc) and water as non-solvents. In this study, the modification of PVDF membrane permeability with PEG additives, CBT variations, and sulfonation was successfully carried out. The membrane solidification process was carried out on three variations of the coagulation bath temperature (CBT): 30, 45, and 60 °C. Eight types of membranes were characterized by using FT-IR and TGA/DSC, followed by the analysis of their porosity, hydrophilicity, water uptake, swelling degree, tensile strength, and permeability of creatinine and urea. The FT-IR spectra indicate that PVDF modification has been successfully carried out. The porosity, hydrophilicity, water uptake, and swelling degree values increase with the modification of functional groups. Furthermore, improvements in creatinine and urea permeability and clearances are achieved by increasing CBT and sulfonation in the PVDF/PEG membrane. The presence of sulfonate groups improves the membrane permeability through the interaction of intermolecular hydrogen with water and dialysate compounds. The existence of PEG as a porogen enhanced membrane porosity. Creatinine and urea clearance values increase from 0.29–0.58 and 6.38–20.63 mg/dL, respectively.

Functionalized Particles Designed for Targeted Delivery.

Pure bioactive compounds alone can only be exceptionally administered in medical treatment. Usually, drugs are produced as various forms of active compounds and auxiliary substances, combinations assuring the desired healing functions. One of the important drug forms is represented by a combination of active substances and particle-shaped polymer in the nano- or micrometer size range. The review describes recent progress in this field balanced with basic information. After a brief introduction, the paper presents a concise overview of polymers used as components of nano- and microparticle drug carriers. Thereafter, progress in direct synthesis of polymer particles with functional groups is discussed. A section is devoted to formation of particles by self-assembly of homo- and copolymer-bearing functional groups. Special attention is focused on modification of the primary functional groups introduced during particle preparation, including introduction of ligands promoting anchorage of particles onto the chosen living cell types by interactions with specific receptors present in cell membranes. Particular attention is focused on progress in methods suitable for preparation of particles loaded with bioactive substances. The review ends with a brief discussion of the still not answered questions and unsolved problems.

Evaluation of 3- and 4-Phenoxybenzamides as Selective Inhibitors of the Mono-ADP-Ribosyltransferase PARP10.

Intracellular ADP‐ribosyltransferases catalyze mono‐ and poly‐ADP‐ribosylation and affect a broad range of biological processes. The mono‐ADP‐ribosyltransferase PARP10 is involved in signaling and DNA repair. Previous studies identified OUL35 as a selective, cell permeable inhibitor of PARP10. We have further explored the chemical space of OUL35 by synthesizing and investigating structurally related analogs. Key synthetic steps were metal‐catalyzed cross‐couplings and functional group modifications. We identified 4‐(4‐cyanophenoxy)benzamide and 3‐(4‐carbamoylphenoxy)benzamide as PARP10 inhibitors with distinct selectivities. Both compounds were cell permeable and interfered with PARP10 toxicity. Moreover, both revealed some inhibition of PARP2 but not PARP1, unlike clinically used PARP inhibitors, which typically inhibit both enzymes. Using crystallography and molecular modeling the binding of the compounds to different ADP‐ribosyltransferases was explored regarding selectivity. Together, these studies define additional compounds that interfere with PARP10 function and thus expand our repertoire of inhibitors to further optimize selectivity and potency.

Total Synthesis of (±)-Jujuyane.

The first total synthesis of (±)-jujuyane, a cyclooctanoid natural product, was accomplished from a (5 + 3) dimerization product of oxidopyrylium ylide that forms the cyclooctanoid core structure along with inherited stereochemical bias. Selective functional group modifications of the highly oxygenated dimeric structure, followed by the tactical functional group manipulation around the eight-membered carbocyclic core, enabled the total synthesis of (±)-jujuyane, which will serve a guide for future applications of oxidopyrylium dimers to the natural product total synthesis.

Optimizing Fe-Based Metal-Organic Frameworks through Ligand Conformation Regulation for Efficient Dye Adsorption and C2 H2 /CO2 Separation.

Regulating the structure of metal-organic frameworks (MOFs) by adjusting the ligands reasonably is expected to enhance the interaction of MOFs on special molecules/ions, which has significant application value for the selective adsorption of guest molecules. Herein, two tricarboxylic ligands H3 L-Cl and H3 L-NH2 were designed and synthesized based on the ligand H3 TTCA by replacing part of the benzene rings with C=C bonds and modifying the chlorine and amino groups on the 4-position of the benzene ring. Two 3D Fe-MOFs (UPC-60-Cl and UPC-60-NH2 ) with the new topology types were constructed. As the C=C bonds of the ligands have flexible torsion angles, UPC-60-Cl features three types of irregular 2D channels, while UPC-60-NH2 has a cage with two types of windows on the surface. The synergistic effect of unique channels and modification of functional groups endows UPC-60-Cl and UPC-60-NH2 with high adsorption capacity for organic dyes. Compound UPC-60-Cl shows high adsorption capacity for CV (147.2 mg g-1 ), RHB (100.3 mg g-1 ), and MO (220.9 mg g-1 ), whereas UPC-60-NH2 exhibits selective adsorption of MO (158.7 mg g-1 ). Meanwhile, based on the diverse pore structure and modification of active sites, UPC-60-Cl and UPC-60-NH2 show the selective separation of equimolar C2 H2 /CO2 . Therefore, reasonable regulation of organic ligands plays a significant role in guiding the structure diversification and performance improvement of MOFs.

Tris(pentafluorophenyl)borane‐Modified P3CT‐K as an Efficient Hole‐Transport Layer for Inverted Planar MAPbI3 Perovskite Solar Cells

AbstractPolythiophene‐acid‐based conjugated polyelectrolytes have shown great potential as hole‐transport materials for the fabrication of inverted planar perovskite devices with decent power conversion efficiencies (PCEs), benefiting from their tunable structure and functional properties. In contrast to the current progress mainly from side functional group modification, here a simple and effective strategy is reported to effectively regulate the aggregation of P3CT‐K through the modification of the thiophene units in the main chain. A small molecule tris(pentafluorophenyl)borane (TPB) is applied as the Lewis acid to interact with the thiophene unit of polythiophene chain and regulate the aggregation of conjugated polyelectrolytes. The control of aggregation of P3CT‐K not only elevates the hole mobility of P3CT‐K, but also suppresses charge recombination in P3CT‐K composite films. Consequently, the high efficiency of inverted MAPbI3 perovskite solar cells is achieved with a peak power conversion efficiency of 20.7% and simultaneously improved short‐circuit current density and fill factor. This work provides an effective method for the aggregation control of the polyelectrolyte hole materials to promote the performance of inverted planar perovskite solar cells.

PH Sensor Through a Self-Assembled Multifunctional Layer With Clitoria Ternatea Based on Long-Period Fiber Gratings

In this study, Clitoria ternatea was used to provide a quantifiable method for pH measurement. The researchers proposed a new pH measurement method that involves the use of a KrF excimer laser to perform laser-assisted etching of the crown structure of long-period fiber gratings. Processing of the front surface of the optical fibers through grating resulted in periodically structured optical fibers with a sensor diameter of 55 μm and a period of 660 μm; these structured optical fibers were encapsulated using glass slides. On the front surface of the optical fibers, functional group modification of the fiber surface was conducted and a nanogold coating was applied using the self-assembly method. Additionally, Clitoria ternatea was bonded to the surface of the optical fibers for the measurement of refractive index. In the pH sensing experiment, the average loss sensitivity detected by the sensors with no nanogold self-assembled coating was 0.0635 dB/pH. By contrast, the average resonant wavelength sensitivity of the sensors with a nanogold self-assembled coating under localized surface plasmon resonance was increased to 0.173 nm/pH. Compared with the sensors with no nanogold self-assembled coating, the sensors with this coating had a wavelength drift sensitivity enhanced by a factor of 37.

Integrated structural and chemical analyses for HCl-supported hydrochar and their adsorption mechanisms for aqueous sulfachloropyridazine removal

In this study, various HCl-supported hydrochar made from root powder of long-root Eichhornia crassipes were applied to adsorb aqueous sulfachloropyridazine (SCP). Adsorption capacity (qe μg g−1) was positively correlated with combined severity-CS. With CS increasing, carbonization degree, hydrophobicity, porosity and isoelectric point of hydrochar increased, but content of polar functional groups decreased. Hydrophobic interaction was important for SCP adsorption. A 24 × 36 peak area table was generated from 24 FT-IR absorbance spectra computed by peak detection algorithm. Afterwards, correlation analysis between qe μg g−1 and FT-IR peak area were conducted, indicating that wavenumbers at 555.4, 1227.47, 1374.51, 1604.5, 2901.4/2919.2 and 3514.63 cm−1 were helpful for SCP adsorption. Further, multivariate linear regression analyses showed that aromatic skeleton and phenolic hydroxyl were the two biggest contributors. Electrostatic attraction did not exist during the SCP adsorption process. Under strong acid condition, protonated amino groups in cationic SCP acting as a hydrogen donator interacted with electron-rich functional groups onto hydrochar by Hydrogen interaction. Under weak acid condition, neutral SCP served as an π electron donor to bond with hydrochar by π-π electron donator-acceptor interaction. This work could guide the functional groups modification strategy of hydrochar to make better use of it in water purification field.

PEMBUATAN DAN MODIFIKASI KARBON AKTIF PELEPAH KELAPA SAWIT (Cocus nucifera L.) SEBAGAI ADSORBEN METILEN BIRU (PREPARATION AND MODIFICATION OF ACTIVATED CARBON FROM PALM OIL (Cocus nucifera L.) AS ADSORBENT OF BLUE METHYLENE)

The methylene blue dye adsorbed by activated carbon from oil palm fronds modified with H2SO4 has been carried out. This study aims to utilize activated carbon from palm oil frond waste (Cocus nucifera L.) as an adsorbent to adsorb toxic methylene blue dye in textile industrial wastewater. The method consisted of several steps, namely: carbonization, carbon activation using 0.3M HCl activator, surface modification, and identification of functional groups using FTIR, characterization of the adsorbent material using SEM, BET, and surface area analysis with methylene blue. The optimal adsorption time of methylene blue by activated carbon is 20 minutes, longer than modified activated carbon which is 15 minutes. Adsorption of methylene blue by activated carbon and modified activated carbon according to the Langmuir isothermal model. The adsorption capacity of activated carbon was lower, namely 9.7847 mg / g compared to the adsorption capacity of modified activated carbon, which was 10.7642 mg / g. This proves that the active carbon modified by H2SO4 is better used as an adsorbent for adsorbing methylene blue dye