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Biodegradable cellulose based on sugarcane bagasse is produced using alkaline treatment followed by bleaching method for dye removal. FTIR, Raman, SEM, EDS, XRD, and N2 adsorption–desorption isotherm analysis were utilized to characterize the surface morphology and functional groups of the sugarcane bagasse (SCB) and treated sugarcane bagasse (TSCB). The TSCB was investigated to remove of Crystal violet (CV) and Methylene blue (MB). Different factors influence the adsorption processes such as contact time, adsorbent dose, dye concentration, temperature, pH, and NaCl dose were studied. The Langmuir model was investigated to study the adsorption equilibrium behavior of CV and MB dyes by TSCB. A maximum adsorption capacities (qmax) of 107.5 and 112.9 mgg−1 was calculated for CV and MB-dyes, respectively. Also, the adsorption processes are physiosorption with average energy values of E = 1.151 and 1.101 KJmol-1 for CV and MB-dyes, respectively. The kinetic data of the investigated processes were controlled by the pseudo-second order (PSO) model with qe,cal (mgg−1) values of 59.3 and 58.9 mgg−1 for CV and MB-dyes, respectively. Suggesting that chemical mechanisms may influence the removal of CV and MB dyes. Overall, TSCB was found to be an effective, environmentally friendly, and low-cost material to remove of cationic dyes in this research.

In this study, coprecipitation method followed by sonochemical treatment was used to prepare layered-double hydroxides (LDH) and graphene oxide-layered-double hydroxides (GO-LDH). GO-LDH and LDH adsorption performance were evaluated using aqueous solution of Methyl Orange dye (MO). The LDH and GO-LDH were characterized using various advanced techniques. The analysis of data collected from the XRD pattern and size distribution showed that the presence of GO will increase the inter-space between the LDH layers and the polydispersity index than pure LDH. This will make the ion exchange be easier and improve the adsorption process. The adsorption kinetic studies presented that the adsorption of MO dye on LDH and GO-LDH follows a pseudo-second-order reaction. Moreover, according to intraparticle diffusion, GO-LDH has a faster diffusion constant for MO molecules than LDH. Furthermore, as predicted by Langmuir, the maximum adsorption ability of MO using GO-LDH (505.1 mgg−1) which was higher than LDH (400 mgg−1). Finally, LDH and GO-LDH were successfully regenerated using 1.0 M NaOH and Methanol, respectively. Moreover, the GO-LDH showed excellent reusability behavior compared to LDH. This suggests that GO-LDH could be a costless adsorbent compared to LDH.

In this work, we study the modification of graphene oxide with polyacrylic acid and acrylamide (GO/PAA/PAM) through free radical single polymerization step to adsorb methylene blue (MB) and crystal violet (CV)-dyes in single and binary-systems from aqueous media. (GO/PAA/PAM) was characterized before and after adsorption processes. Thermogravimetric analysis provides useful data about the functionalization process, where the polymers will be bounded with the GO at the surface OH groups and the composite mainly composed of the polymers chains. The adsorption kinetic obeys the pseudo-second-order for the two dyes in the single and binary systems. Moreover, according to Langmuir isotherm in the single systems, the sorption of CV (357.14 mg g−1) is more than MB (344.8 mg g−1). On contrary, in the binary system, the MB (323.56 mg g−1) is preferably adsorbed by the (GO/PAA/PAM) composite than CV (172.41 mg g−1). Furthermore, the (GO/PAA/PAM) composite exhibited acceptable recycling over five runs. Finally, a real dye sample was applied to appreciate the efficiency of the prepared material in the industrial field. This novel composite can be used on a large scale for purification, remediation, and numerous industrial processes due to its promising properties.

A novel series of bis- (Abdelhamid et al., 2017; Banerjee et al., 2018; Bharanidharan et al., 2022)thiadiazoles was synthesized from the reaction of precursor dimethyl 2,2′-(1,2-diphenylethane-1,2-diylidene)-bis(hydrazine-1-carbodithioate) and hydrazonyl chlorides in ethanol under ultrasonic irradiation. Spectral tools (IR. NMR, MS, elemental analyses, molecular dynamic simulation, DFT and LUMO and HOMO) were used to elucidate the structure of the isolated products. Molecular docking for the precursor, 3 and ligands 6a-i to two COVID-19 important proteins Mpro and RdRp was compared with two approved drugs, Remdesivir and Ivermectin. The binding affinity varied between the ligands and the drugs. The highest recorded binding affinity of 6c with Mpro was (−9.2 kcal/mol), followed by 6b and 6a, (−8.9 and −8.5 kcal/mol), respectively. The lowest recorded binding affinity was (−7.0 kcal/mol) for 6 g. In comparison, the approved drugs showed binding affinity (−7.4 and −7.7 kcal/mol), for Remdesivir and Ivermectin, respectively, which are within the range of the binding affinity of our ligands. The binding affinity of the approved drug Ivermectin against RdRp recoded the highest (−8.6 kcal/mol), followed by 6a, 6 h, and 6i are the same have (−8.2 kcal/mol). The lowest reading was found for compound 3 ligand (−6.3 kcal/mol). On the other side, the amino acids also differed between the compounds studied in this project for both the viral proteins. The ligand 6a forms three H-bonds with Thr 319(A), Sr 255(A) and Arg 457(A), whereas Ivermectin forms three H-bonds with His 41(A), Gly143(A) and Gln 18(A) for viral Mpro. The RdRp amino acids residues could be divided into four groups based on the amino acids that interact with hydrogen or hydrophobic interactions. The first group contained 6d, 6b, 6 g, and Remdesivir with 1–4 hydrogen bonds and hydrophobic interactions 1 to 10. Group 2 is 6a and 6f exhibited 1 and 3 hydrogen bonds and 15 and 14 hydrophobic interactions. Group 3 has 6e and Ivermectin shows 4 and 3 hydrogen bonds, respectively and 11 hydrophobic interactions for both compounds. The last group contains ligands 3, 6c, 6 h, and 6i gave 1–3 hydrogen bonds and 6c and 3 recorded the highest number of hydrophobic interactions, 14 for both 6c and 6 h. Pro Tox-II estimated compounds’ activities as Hepatoxic, Carcinogenic and Mutagenic, revealing that 6f-h were inactive in all five similar to that found with Remdesivir and Ivermectin. The drug-likeness prediction was carried out by studying physicochemical properties, lipophilicity, size, polarity, insolubility, unsaturation, and flexibility. Generally, some properties of the ligands were comparable to that of the standards used in this study, Remdesivir and Ivermectin.

Pyrazolo[3,4-d]pyrimidine had been attracted awesome interest due to its pharmacological potential especially as an anticancer. Several mechanisms of action were accounted for the anticancer potential of this privileged scaffold. Previous researches explained its role in binding with many receptors as cyclin-dependent kinases, epidermal growth factor receptor, Src kinase, m-TOR, and JAK kinase. Nevertheless, there is an incredible demand for the discovery of target-oriented compounds. In this review, we shed the light on the antitumor potential of this important fused heterocyclic system, different mechanisms of actions of this ring, and SAR studies towards many targets in a trial to pave the way for medicinal chemists to optimize this ring system in order to discover new anticancer agents with better selectivity and increased anticancer potential.

In this study, the separation of lanthanides from phosphate ore using oxalic acid (C2H2O4), tartaric acid (C4H6O6), lactic acid (C3H6O3), sulfuric acid (H2SO4) and hydrochloric acid (HCl) was investigated. The ore was characterized before and after leaching processes by X-ray fluorescence (XRF), Scanning electron microscope (SEM), X-ray powder diffraction (XRD), and Fourier transform infrared (FTIR). The different parameters affect the leaching rate such as leaching time, acid concentration, liquid/solid ratios, temperature, and leaching kinetics were studied. The optimal leaching conditions were determined as 0.4 M C2H2O4, 2.5 M C4H6O6, 1.8 M C3H6O3, 2.0 M H2SO4, and 3.0 M HCl, with a liquid/solid (L/S) mass ratio of 6/1 C2H2O4, 8/1 for both C4H6O6 and C3H6O3, 5/1 for both H2SO4 and HCl at 30 °C, agitation rate ≈ 350 rpm and particle size ≈ 144.8 μm. Under these optimum conditions, the recovery percentage (%R) was 42.8% (for C2H2O4), 93.2% (for C4H6O6), 89.1% (for C3H6O3), 89.3% (for H2SO4), and 74.6% (for HCl). SEM and FTIR characterizations for the residue were investigated. Experimental data reveal that the leaching processes are fitted by chemical reaction models for C2H2O4 and C3H6O3, and by diffusion-reaction model for C4H6O6, H2SO4, and HCl. The activation energies for these models were estimated to be 43.3, 30.33, 45.8, 31.3, and 38.6 kJ/mol for C2H2O4, C4H6O6, C3H6O3, H2SO4, and HCl, respectively. All data were confirmed and explained by XRD, FTIR, and SEM studies.

Acid leaching for different types of mixed spent Li-ion mobile batteries is carried out after alkali decomposition using NH4OH followed by H2SO4 + H2O2 leaching. In the alkali decomposition step, the effects of reaction time, NH4OH concentration, liquid/solid mass ratio and reaction temperature on the decomposition process are investigated to remove Al, Cu, Mn, Ni, Co, and Li. After alkaline treatment, the alkali paste is treated to leach the remaining metals using H2SO4 + H2O2. The significant effects of reaction time, acid concentration, H2O2 concentration, liquid/solid mass ratios and reaction temperature on the leaching rate are studied. More than 97% of Al, Mn, Ni, Co, and Li and about 65% Cu are leached in two stages. Kinetic analysis shows that, the data fit with chemical reaction control mechanism and the activation energies for the investigated metals using the Arrhenius equation ranged from 30.1 to 41.4 kJ/mol. Recovered metals are precipitated from the leaching liquor at varying pH values using NaOH solution and Na2CO3. Firstly, Mn is precipitated as MnCO3 at pH = 7.5. Secondly, at pH = 9.0, nickel is precipitated as NiCO3. Thirdly, as the pH of the leaching liquor reaches 11–12, Co(OH)2 is precipitated and the remaining Li is readily precipitated as Li2CO3 using a saturated Na2CO3 solution. Based on the experimental data, a flow sheet is developed and tested for the recovery process.

Leaching and recovery processes for zinc and copper from brass slag by sulfuric acid were carried out and iron and aluminum were also precipitated as hydroxides in addition to silica gel. The factors affecting the performance and efficiency of the leaching processsuch as agitation rate, leaching time, acid concentration and temperature were separately investigated. The results obtained revealed that zinc and copper are successfully recovered from these secondary resources, where the percent recovery amounts to 95% and 99% for zinc and copper, respectively. The experimental data of this leaching process were well interpreted with the shrinking core model under chemically controlled processes. The apparent activation energy for the leaching of zinc has been evaluated using the Arrhenius expression. Based on the experimental results, a separation method and a flow sheet were developed and tested to separate zinc, copper, iron, aluminum and silica gel from the brass slag.