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The composites of polyaniline (PANI) with reduced graphene oxide (PANI/rGO) and metals of iron, copper, and cobalt have been synthesized and coated on the nickel foam (NF) priors to measurement in three electrodes system to investigate the electrochemical properties. Surface area of PANI increased from 48.371 ㎡/g to 69.091 ㎡/g after compositing with rGO and the capacitance changed from 246.50 F/g to the highest capacitance 285.89 F/g in the form of PANI/rGO-Cu. Meanwhile, PANI/rGO-Co and PANI/rGO-Fe showed lower capacitance with 250.047 F/g and 254.71 F/g, respectively. Capacitance of bi-and tri-metal content was lower than PANI.

This research studied the effect of transition metals (TMs) in one period (TMs = Fe, Co, Ni, Cu, and Ag) on the characteristics of mordenite zeolite. The loading method used was wet impregnation with 0.025 M metal salt concentrate. The results showed that TMs could be impregnated on mordenite, which was indicated by a shift in the wavelength of certain functional groups. However, the metal loading did not cause a change in the diffraction pattern of mordenite. The periodicity of transition metals impacts the strength of acidity and texture of the catalyst, where the optimum strength of acidity, surface area, pore-volume, and average pore radius is Co/Mor. Morphological analysis showed that TMs/mordenite catalyst was more heterogeneous than mordenite., Moroccan Journal of Chemistry, Vol. 10, No 3 (2022): in progress

Mesoporous sodalite nanoparticles were directly synthesized from Indonesian kaolin with the addition of CTABr as a mesopore template. The studies highlighted the importance of aging time (3-12 h) and temperature (50-80 °C) on increasing surface area and mesoporosity of sodalite. Indonesian kaolin was used without pre-treatment and transformed to sodalite following the initial molar composition of 10 Na

Biosurfactants are surface-active compounds produced by a wide variety of diverse microorganisms. The structural diversity of biosurfactants depends on microorganisms and growth conditions (such as substrate and pH). The unique structure of biosurfactants provides unique properties for specific applications. Biosurfactant production still needs to be explored using a variety of microorganisms and growth conditions for producing the diversity of biosurfactant structures. Production and characterization of biosurfactant by Lactobacillus lactis using Crude Palm Oil (CPO) as an additional carbon source has been conducted. The optimization condition of biosurfactant production by L. lactis using media containing various concentrations of CPO was evaluated. Optical density, surface tension, and emulsification index were observed daily for 12 days. Optimal biosurfactant production condition was achieved when L. lactis was grown on media Nutrient Broth containing 10% (v/v) of CPO and incubated for 8 days. Biosurfactants were obtained for 80 mg/L media. Based on Thin Layer Chromatography (TLC) analysis and Fourier Transform Infra-Red (FT-IR) Spectroscopy, produced biosurfactant was identified as a glycolipid biosurfactant containing functional groups of hydroxyl, ester, carboxylic, methyl, and methylene. Produced biosurfactants exhibited the Critical Micelle Concentration (CMC) value of 1 g/L with a surface tension value of 49.46 mN/m. The emulsion system of produced biosurfactant was water in oil (w/o). The produced biosurfactant showed an emulsification index of 41-71% with soybean oil, palm oil, sunflower oil, olive oil, and lubricant oil. The stable emulsion was reached up to 30 days when soybean oil, olive oil, and lubricant oil were used as the water-immiscible compound.

This research prepared a TiO2, ZnS, and ZnS-TiO2 film on a carbon fiber, to produce TiO2/C-fiber, ZnS-C-fiber, and ZnS-TiO2/C-fiber by Chemical Bath Deposition (CBD). Results show that TiO2/C-fiber consist of anatase at 2θ 25.3 o and 54.6 o, rutile at 2θ 43.5 o and a carbon characteristic peak at 2θ of 24.5 o. Meanwhile, the characteristic peaks of ZnS on ZnS-TiO2/C-fiber present at 2θ of 27.91 o and 54.58 o. TiO2/C-fiber has a band gap energy of 3.60 eV, the ZnS/C-fiber of 3.73 eV; when those two catalyst combine, the gap energy is 3.15 eV indicating the interface charge transfer between ZnS-TiO2. Photocatalytic treatment of an isopropanol solution with TiO2/C-fiber as a catalyst and under UV light radiation present results peaks at 222- 224 nm and 265 nm, indicating the electronic transition of acetone. Meanwhile, the isopropanol degradation with ZnS-TiO2/C-fiber produced a new peak at 234-237 nm. The Quantum Yield, QY, of ZnS-TiO2/C-fiber is 6.96 x 10-4, higher than TiO2/C-fiber, i.e., 0.42 x 10-4. It indicates that ZnS provides a significant role in the photocatalytic activity through a red shift of light response and decreasing electron-hole recombination.

This study aims to fabricate bio-composites of hydroxyapatite/shellac/sorghum as bone scaffold material in biomedical applications. Hydroxyapatite is made from bovine bone powder, while shellac is the end product from processing lice with adhesive properties, which are biodegradable and non-toxic. Furthermore, sorghum was used as a pore-forming material. The production of the materials was carried out using dry method which was sintered at a temperature of 1000°C. Subsequently, characterization of the bio-composites was carried out through X-Ray Diffraction, Scanning Electron Microscopy and Fourier Transform Infrared. The results of hardness and compression test were compared using pure hydroxyapatite and human bone as gold standard material. Furthermore, the biodegradation rate of these materials was also reported.

Research has been carried out on the synergism of a mixture of andisol soil and foundry sand as Cu(II) ion adsorbent. This study aims to determine the effect of mixing andisol soil and foundry sand on the absorption of Cu (II) ions and to study the type of isotherm and its adsorption kinetics model. The adsorbent was activated with 3 M NaOH. The acidity of the adsorbent was analyzed using the specific total acidity test method. The final concentration of Cu (II) ions was analyzed using AAS (Atomic Absorption Spectroscopy). The optimum adsorption conditions were obtained based on variations in composition, pH, and contact time. The adsorbent was made with variations in the composition of andisol: foundry sand 100:0, 75:25, 50:50, 25:75 and 0:100 (w/w). The effect of adsorption conditions was carried out by varying the pH of the copper (Cu) solution from 3-7. The effect of contact time was varied at 15-135 minutes with 15 Minute intervals.

Two novel coordination polymers (CPs) based on zinc(II) and acyclic dicarboxylate linkers, i.e. [Zn2(μ3-IA)2(H2O)4]n (1-W) and {[Zn2(μ-IA)2(DMF)]·H2O}n (2-DMF) (where IA2− = itaconate) have been obtained as a result of a systematic study of some synthetic factors such as pH and solvents, which has allowed optimizing the conditions that render the best yields. 1-W is obtained as X-ray quality single crystals upon which diffraction analysis has been conducted, showing that it consists of a neutral 2D layered structure. Some structural details have been elucidated for 2-DMF based on a comparison of PXRD data with 1-W and in view of the similar composition of both crystalline phases. Photoluminescence (PL) measurements confirm that 2-DMF presents slightly different spectra from those of 1-W. Time-dependent density functional theory (TD-DFT) calculations of 1-W reveal that electronic transitions arise from both first excited singlet and triplet states involving ligand-centred emissions. Moreover, both compounds exhibit blue fluorescence and green phosphorescence that involves less frequent long-lasting phosphorescence (LLP) at 10 K. Exhaustive characterization of long-lasting phosphorescence by means of time-resolved spectroscopy reveals remarkably long lifetimes (τ) of ca. 352 ms (λem ≈ 550 nm) for 1-W and 547 ms (λem ≈ 500 nm) for 2-DMF.

Pembuatan kompos dari sampah dapur dan taman dengan bantuan effective microorganism (EM4) dan microorganism local (MOL) telah dilakukan. Tujuan dari kegiatan ini adalah memanfaatkan sampah yang ada di sekitar untuk dijadikan barang yang lebih berguna. EM4 merupakan kultur campuran dari mikroorganisme yang menguntungkan yang mengandung mikroorganisme fermentasi dan sintetik yang terdiri dari bakteri Asam Laktat (Lactobacillus Sp), bakteri Fotosentetik (Rhodopseudomonas Sp), Actinomycetes Sp, Streptomyces Sp dan Yeast (ragi) dan Jamur pengurai selulose. Bahan ini membantu fermentasi bahan organik tanah menjadi senyawa organik yang mudah diserap oleh akar tanaman. Proses pembuatan kompos dilakukan dengan mencampurkan sampah dapur dan taman dengan penambahan EM4. Proses fermentasi dilakukan variasi waktu 10, 14, 21, 26 dan 32 hari. Hasil pengamatan menunjukkan bahwa semakin lama fermentasi kompos yang dihasilkan semakin baik dimana daun telah hancur berubah bentuk seperti tanah.Kitchen and Garden Waste Composting using EM4 Activator. Composting of kitchen and garden waste with the help of effective microorganisms (EM4) and microorganism local (MOL) has been carried out. The purpose of this activity is to use the waste to become more useful items. EM4 is a mixed culture of beneficial microorganisms. This material contains microorganisms consisting of lactic acid bacteria (Lactobacillus Sp), photosynthetic bacteria (Rhodopseudomonas Sp), Actinomycetes Sp, Streptomyces Sp, and yeast, and cellulose-decomposing fungi. This activator helps break down soil organic matter into organic compounds that are easily absorbed by plant roots. The composting was done by mixing kitchen and garden waste with the addition of EM4 and MOL. The fermentation process was carried out in variations of 10, 14, 21, 26, and 32 days. The results showed that the longer the fermentation time the better the compost was produced indicating by the leaves had crumbled into shape like the soil.

Copper(II)-sulfapyridine complex has been successfully synthesized by 1:4 mole ratio of CuSO4·5H2O and sulfapyridine in methanol as solvent. Indication of the complex formation was shown by shifting of maximum wavelength (λmax) of UV-Visible (UV-Vis) spectra towards smaller than CuSO4·5H2O from 816 nm to 793 nm. Atomic Absorption Spectroscopy (AAS) analysis showed the percentage of copper to be 4.93% corresponding to the theoretical value of copper content in Cu(sulfapyridine)4SO4(H2O)x (x= 3, 4, or 5). Thermogravimetric and differential thermal analysis showed a mass reduction of 4.3% which was equivalent to the evaporation of three molecules of lattice water. The cation and anion charge ratio of the complex was 1:1. Infrared analysis indicated the functional groups of NH2 from sulfapyridine were coordinated to center atom Cu2+. The formed complex was paramagnetic with the effective magnetic moment of 1.82 BM. The broadband peak of UV-Vis spectrum showed a at 793 nm (12610 cm-1) due to d–d [ 2B1g→2Eg−(v1)(dx−y22→dyz) ] transition. From the data, the proposed formula of the complex was [Cu(sulfapyridine)4]SO4·3H2O with square planar geometry.

Compound 5,15-diphenyl porphyrin (DPP) has been synthesized and inserted with different kind of metal (Fe, Cu and Zn). Synthesis of DPP has been carried out through three stages reaction using pyrrole and benzaldehyde as starting materials. Identification of synthesized compounds of 5-phenyl dipyrromethane (DPM) and 5, 15-diphenyl porphyrin (DPP) was confirmed with H-NMR. Three different metals were then inserted into the cavity of DPP. Optical spectra of Cu, Fe, Zn-DPP was then investigated and compared with free-base DPP using UV/Vis spectrophotometer. The result showed that the yield reaction of DPM reached about 41.77% and DPP reached about 21.80%. Based on the spectra investigation of metal-DPP, it showed that DPP had different Soret and Q band when each Cu (II), Fe (II), Zn (II) was inserted into DPP. Moreover, Zn-DPP has Q band at to the rightest shifting than Cu-DPP or Fe-DPP which means it has the least excitation energy among them. Therefore, Zn-DPP has the more potential to be utilized for application such as DSSC.

Access to clean water increases in the future due to world population growth, climate change, water pollution by industrial and household waste, and water scarcity that occurs in several countries worldwide. Seawater desalination is the fastest and most convenient way to meet the needs of clean water that continues to grow today and in the future. In this study, a forward osmosis (FO) membrane has been prepared from chitosan polymer study for seawater desalination. The FO Chitosan membranes are prepared by casting the chitosan polymers in 1% (v/v) acetic acid on the support and evaporating the printing solution at room temperature. The membrane preserves asymmetric structure with 33.67 % of porosity and 15.76 % of a swelling degree. The chitosan membrane has excellent mechanical strength with the tensile strength of 29.67 kgf/mm2 and elongation equal to 8.21%. The performance of the FO process was studied using fructose, sucrose, and a mixture of fructose and sucrose as a withdrawal solution for extracting water from seawater as a feed solution. The clean water flux increases with the addition of the concentration of the draw solution in the forward osmosis process. The parameter quality of all the produced-water agreed to Indonesian government regulation of drinking water quality. The chitosan forward osmosis membrane can be an alternative method for producing drinking water from seawater.

Bio-impedance based sensor using organic polymer-membrane was presented in this paper. The Ca-alginate with glycerol as plasticizer used in the experiments was fabricated by slip casting method on a glass substrates. After atmospheric heating treatment of edible films at 60°C for 24 hours, the films-membranes of 50 mm were obtained. Bio-impedance characterizations were carried out by LCR meter at room temperature. The experiment results showed that the sensor finely operated at low frequency i.e. less than 40 kHz. Response of the sensor increased with the increase of samples mass and became constant after a critical mass. Finally, bio-impedance responses of beef and pork were clearly indicated by a different magnitude that it is possible to apply the films-membranes as bio-sensor applications.

The complex of tetrakis(2-amino-3-methylpyridine) copper(II) sulfate tetrahydrate was synthesized in mol ratio of 1:6 metal to ligand in methanol. The characterization of complex was perform include copper in the complex, TG/DTA, conductivity measurement and UV-Vis spectra. Comparative study of antibacterial activity of 2-amino-3-methylpyridine ligand, metal ion (Cu2+), and the complex indicates that complex exhibited enhanced activity than free ligands and Cu(II).

Preparation of Cu(II) template carboxymethyl chitosan (CMC) cross-linked with Bisphenol A Diglycidyl Ether (BADGE) (CMC-BADGE-t) have done. The synthesis has been done through four step i.e. synthesis carboxymethyl chitosan, adsorption Cu(II) on CMC, crosslinking with BADGE, and desorption Cu(II) from adsorbent. The adsorbent was insoluble in acetic acid solution. FTIR spectrum and SEM-EDX analysis showed that the synthesis has been successfully done. Application of the adsorbent for adsorption Cu(II) ions has optimum pH at 6 and contact time of 60 min. Adsorption kinetics followed pseudo-second order equation, and adsorption isotherms followed Langmuir isotherm adsorption. Maximum adsorption capacity of Cu(II) ions on CMC-BADGE-t was 0.276 mmol/g. The relative selectivity factor (αT) value of Cu(II)/Zn(II), Cu(II)/Cd(II) and Cu(II)/Pb(II) were 50.55, 1.48, and 7.85 respectively that were greater than 1. This adsorbent could be used for several times without loss of adsorption capability.

The chemical vapor deposition (CVD) synthesis of magnetic carbon nanotubes (mCNT) using carbon dioxide/carbon catalyst has been successfully carried out in various pressures. The temperatures were set at 800° C for 10 minutes reaction time. Nitrogen (N2) gas in 20 Torr was flown in followed by ethanol vapor until the final pressure reached 80 and 100 Torr without added air, and 180 Torr with added air. The formation of mCNT was confirmed by shifted X-ray diffraction (XRD) peak of graphite from 26.53° to 25.53° which were highly considered to the other carbon allotropes with sp2 hybridized carbon atom hybridization structures. The higher pressure with added atmospheric air led to the excessive oxidation which influenced the growth of mCNT. Transmission electron microscopy (TEM) analysis observed mCNT filled by catalyst particles which suggested as magnetic phase induced the magnetic property of mCNT. The best electrical conductivity performance (lower electrical resistance) was owned by mCNT produced in the lower pressure condition with no air added.

The carbon nanotube has widely taken great attractive in carbon nanomaterial research and application. One of its preparation methods is catalytic chemical vapor deposition (CCVD) using catalyst i.e. iron, nickel, etc. Generally, except the catalyst, carbon source gasses as the precursor are still required. Here, we report the use of the bifunctional material of Fe3O4/C which has an incorporated core/shell structures of carbon-encapsulated iron compound nanoparticles. The bifunctional catalyst was prepared by submerged arc discharge that simply performed using carbon and carbon/iron oxide electrodes in ethanol 50%. The prepared material was then used as a catalyst in thermal chemical vapor deposition at 800°C flown with ethanol vapor as the primer carbon source in a low-pressure condition. This catalyst might play a dual role as a catalyst and secondary carbon source for growing carbon nanotubes at the time. The synthesized products were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. The successful formation of carbon nanotubes was assigned by the shifted X-ray diffracted peak of carbon C(002), the iron oxides of Fe3O4 and γ-Fe2O3, and the other peaks which were highly considered to the other carbon allotropes with sp2 hybridization structures. The other assignment was studied by electron microscopy which successfully observed the presence of single-wall carbon nanotubes. In addition, the as-prepared carbon nanotubes have a magnetic property which was induced by the remaining of metal catalyst inside the CNT.

Chitosan has been made from chitin that was deacetylated from escargot (Achatina fulica). The purification of chitin was done by deproteination, demineralization, and depigmentation. Identification of chitin and chitosan was done by FTIR (Fourier Transform Infrared) and XRD (X-Ray Diffraction). Characterization of chitosan was determined by water and mineral content, molecular weight, polymerization degree and degree of deacetylation. The result of research was obtained chitosan 6,95%, crystal, white brownish color, odorless, 3,26±0,45% water content, 10,11±0,38% mineral content, 889,78 molecular weight average with degree of polymerization 5 and degree of deacetylation 74,78-77,99%.

The modification of carbon-based nanomaterials with metals is widely studied due to its unique properties. Here, the modification of carbon nanomaterial with iron oxide has been successfully carried out. This modification was achieved using arc discharge in 50% ethanol liquid media. The anode used in the arc discharge was prepared from a mixture of carbon and iron oxide that was synthesized in electrolysis and was then calcined at 250°C with silicon binder with a mass ratio of 3:1:1, and the cathode used was graphite rod. Both electrodes were set in the nearest gap that could provide an arc during arc-discharging, leading to carbon-based nanoparticle formation. The diffractogram pattern of the X-ray diffraction of the fabricated nanoparticles confirmed the typical peak of carbon, iron oxide and iron. The magnetization value of the result analysis of the vibrating sample magnetometer was 9.9 emu/g. The bandgap energy measurement using diffuse reflectance ultra violet was estimated to be 2.18 eV. Using the transmission electron microscopy, the structure of the nanomaterial produced was observed as carbon-encapsulated iron compound nanoparticles.

Complex of cobalt(II) with sulfisoxazole (slfs) has been synthesized in 1 : 4 mole ratio of metal to ligands in methanol, the complex formula is [Co(slfs)3(H2O)3]SO4.nH2O. The electric conductivity of the complex in methanol correspond to 1:1 electrolyte. The thermal analysis indicates that complex contain some hydrates. Magnetic Susceptibility measurements show that the complex is paramagnetic with µeff = 4,60(9) BM. Infra red spectra indicates that the primary N-H group coordinated to the center ion, it is signed by a shift of primary N-H group absorption. UV-Vis spectrum appears one peak at λ= 515,5 nm (19.342 cm-1) due to transition peak of 4T1g (F) → 4T2g (P) (ν3) overlay to transition peak of 4T1g(F) → 4A2g(F) (ν2). The value of 10 Dq (Δo) that corresponds to transition 4T1g → 4T2g (n1) is 95,29 kJ.mol-1. Cyclic voltammograms have revealed quasi reversible. The complex probably is octahedral. Keywords: cobalt(II), sulfisoxazole, complex, paramagnetic, octahedral

Study on chitosan modification by swelling and crosslinking and its application as a selective adsorbent for heavy metals Cr (VI) in batik industry wastes was done. Swelling is intended to improve chitosan porosity, whereas crosslinking is to increase the resistance of chitosan against acid. Natural samples are generally acidic, thus limiting chitosan application as an adsorbent. Modification of chitosan by combining swelling and crosslinking is expected to increase its adsorption capacity in binding heavy metal ions in water. The modified chitosan was later contacted with Cr (VI) to test its adsorption capacity with a variation of pH and contact time. Finally, application of modified chitosan was done in batik industry waste containing Cr (IV). Based on the results, chitosan-ECH 25% (v/v) was the optimum concentration of crosslinker to adsorb Cr (VI) ions. Modified chitosan has a solubility resistance to acids, even though a strong acid. Modification of chitosan also improved its adsorption capacity to Cr (VI) from 74% (pure chitosan) to 89% with contact time 30 min at pH 3. On the application to the batik wastes, the modified chitosan were able to adsorb Cr (IV) up to the level of 5 ppm. Thus, the modified chitosan has a potential to be applied to as an adsorbent of Cr (VI) in batik industry wastes.

The aim of this research was to improve the adsorption capacity of chitosan by modification of the chitosan using various cross-linking agents and followed by grafting using succinate anhydride. Succinate anhydride was grafted into chitosan that had been cross-linked using ethylene glycol di-glycidyl ether (EGDE), diethylene glycol diglycidyl ether (DEGDE) andbisphenolAdiglycidyl ether (BADGE) on the hydroxyl group of chitosan to yield Chit- EGDE-Suc, Chit-DEGDE-Suc, and Chit-BADGE-Suc, respectively. Modified chitosans were analyzed using FTIR and TG-DTA and then applied as adsorbents for Pb(II) ion. Adsorption was carried out in batch condition with a variation of solution pH, contact time, and concentration of Pb(II) in the solution. Adsorption ofPb(II) ion reached optimum condition at pH 5 and contact time of 120 minutes. Adsorption of Pb(II) ion on all of the adsorbents fit well the pseudo-second order kinetic equation. Adsorption capacities of Pb(II) on Chit-EGDE-Suc, Chit-DEGDE-SucdanChit-BADGE-Suc were 0.333, 0.388 and 0.898 mmolg-1, respectively, which mean that the adsorption of Chit-BADGE-Suc was the highest and followed by Chit- DEGDE-Suc and Chit-EGDE-Suc.