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All Journal Jurnal Bahan Alam Terbarukan Communications in Science and Technology ASEAN Journal of Chemical Engineering REACTOR : Journal of Research On Chemistry And Engineering

Chafidz, Achmad

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Author-ID : 1157106

Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Energy Engineering Materials Science & Nanotechnology

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Articles

Title

Enhancing thermal and mechanical properties of polypropylene using masterbatches of nanoclay and nano-CaCO3: A review Chafidz, Achmad
Communications in Science and Technology Vol 3 No 1 (2018)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

Polymer nanocomposites (PNCs) can be considered as promising relatively new types of composite materials. PNCs give opportunity to develop new composites materials with different structure-property relationships compared to their conventional micro/macro scale composites. Polyolefin based nanocomposites nowadays become more important, because this type of composites has been largely used in various industries. For example, polypropylene based nanocomposites have been widely used in automobile â€“ related industries to replace their conventional composites. This review paper will focus on the polypropylene based nanocomposites prepared using masterbatches of nanoclay and nano-CaCO3 via melt compounding method. The thermal and mechanical properties of such nanocomposites were also discussed.

Formation of fine particles using supercritical fluid (SCF) process: Short review Chafidz, Achmad; Jauhary, Thonthowy; Kaavessina, Mujtahid; Sumarno, Sumarno; Latief, Fahamsyah H.
Communications in Science and Technology Vol 3 No 2 (2018)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

This paper will discuss about the utilization of supercritical fluid (SCF) process to produce fine particles. Supercritical fluids (SCFs) process can be considered as an emerging “clean” technology for the production of small-size or fine particles (e.g. micron-size). Microsphere is a material in micron scale which has been widely used as adsorbent, catalyst support, and drug delivery system. For advanced application, those materials are formulated in the form of porous microspheres. There are several methods that can be used using SCFs. Those method are, Rapid Expansion of Supercritical Solution (RESS), Gas Anti-Solvent/Supercritical Anti-Solvent (GAS/ SAS), Aerosol Solvent Extraction System (ASES), dan Solution Enhanced Dispersion by Supercritical Fluids (SEDS) and Particle from Gas-Saturated Solutions/Suspensions (PGSS). Considering the morphology of material which will be used to prepare microsphere, each of methods above has specific advantages and disadvantages toward the material. Based on the literatures, the ASES method is more likely to produce porous microparticles (microspheres). In the ASES method, porous microsphere formation is the result of interactions between: degrees of supersaturation, nucleation velocity and crystal growth.

Utilization of extracellular polymeric substances (EPS) immobilized in epoxy polymer as double ion exchanger biosorbent for removal of chromium from aqueous solution Kistriyani, Lilis; Salimin, Zainus; Chafidz, Achmad
Communications in Science and Technology Vol 5 No 1 (2020)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

Cation and industrial pollutant anions are removed from wastewater using organic cation and anion exchange resin. "Extracellular Polymeric Substance" (EPS) from bacterial extraction can accumulate cation and anion elements through biosorption by adsorption mechanism, ion exchange, formation of complex compounds and hydrogen bonds. EPS can be used as an biosorbent and ion exchange bioresin replacing organic resins, because EPS contains organic functional groups that are negatively charged (RCOOH, ROPO3H, ROPO3Na, ROSO3H, ROSO3Na, etc.) cation absorbers and positively charged (ROH, RCNH2HCOOH, etc.) anion absorber. EPS consists of 40-95% polysaccharide compounds, protein 1-60%, nucleic acids 1-10%, lipids 1-10% and the remaining amino acid polymers and other compounds. The tannery industry produces trivalent (Cr+3) chromium pollutants at levels of 15.2 ppm and hexavalent (CrO4-2 or Cr2O7-2) levels of 0.77 ppm which exceeds the standard quality for a total Cr of 0.6 ppm. Cr pollutants are very dangerous for human health. Research had been done on the use of immobilized EPS bioresin in epoxy polymers for chromium binding. EPS was extracted from bacterial activated sludge by centrifugation at 9000 rpm for 20 minutes at 4°C, the filtrate was EPS. The analysis showed EPS content were 16% fat, 12% carbohydrate, and 16% protein. The functional group analysis results with infrared ray spectroscopy (FTIR) showed EPS containing chemical bonds such as -CH, -OH, -NH, and -C=O which proved that EPS extraction contained RCOOH, ROH, and RCNH2HCOOH functional components which were exchanging components cations and anions. Epoxy polymers were prepared by mixing bisphenol A monomers and 1: 1 ratio epichlorohydrin. Immobilized EPS double ion exchange biorecin in epoxy polymers was prepared by mixing 200 mg EPS and 1800 mg epoxy. The binding of chromium ions in the resin was carried out by recirculating the chromium solution through a burette column filled with 2 rams of bioresin at pH 5, 6 and 7. The optimum results gave chromium ion absorption efficiency of 89.20% at pH 5. Column operations could be optimized by varied the amount of bioresin used.

Production of silver nanoparticles via green method using banana raja peel extract as a reducing agent Chafidz, Achmad; Afandi, Amira Rahmani; Rosa, Bunga Mela; Suhartono, Jono; Hidayat, Pratikno; Junaedi, Harri
Communications in Science and Technology Vol 5 No 2 (2020)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21924/cst.5.2.2020.223

In this study, biosynthesis of silver nanoparticles using the extract of a local banana peel (variant name: Raja) as bio-reductor was carried out. This study aimed to determine the effect of two different ratios of Banana Peel Extract (BPE)/distilled water on the synthesis of silver nanoparticles. The two of BPE/water ratios were 1% (v/v) and 5%(v/v), named as Sample A and Sample B, respectively. Whereas, the concentrations of AgNO3 solution as the precursor were varied as follows: 0.125; 0.1; 0.075; and 0.05 M. The synthesized colloidal silver nanoparticles were characterized using a UV-Vis spectrometer, while the BPE solution was analyzed using Fourier Transform Infra-Red (FT-IR) to study its functional groups. While, the solid silver nanoparticles was characterized using a Scanning Electron Microscopy (SEM) with an Energy-dispersive X-ray spectroscopy (EDX) analysis. The UV-Vis spectrometer results qualitatively showed that sample A produced better silver nanoparticles than that of sample B. All samples showed absorbance peaks at wavelength of 450 nm. It was found that the highest absorbance value (i.e. 1.59) occurred at sample A with a concentration of AgNO3 solution 0.1 M. Additionally, FT-IR analysis result showed the presence of a hydroxyl group specifically for alcohols as phenols, which indicated the possibility of polyphenol compounds. The SEM micrograph showed that some of the silver nanoparticles were in the shape of tetrahedron or triangular like particle and spherical The SEM image analysis results using ImageJ software showed that most of the silver nanoparticles produced had the size of 100-300 nm. Furthermore, the EDX analysis result showed a peak count at 3 keV, which confirmed the formation of silver nanoparticles.

Investigating potential application of bio-based polymeric surfactant using methyl ester from palm oil for chemical enhanced oil recovery (CEOR) Wibowo, Agam Duma Kalista; Megawati, Rizki; Setyaningrum, Vilia Kartika; Putri, Erika Wahyu; Joelianingsih; Handayani, Aniek Sri; Solikhah, Maharani Dewi; Chafidz, Achmad
Communications in Science and Technology Vol 8 No 2 (2023)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21924/cst.8.2.2023.1318

Fatty Acid Methyl Ester (FAME) or palm oil methyl ester is one of the palm oil derivatives in which one of the anionic surfactants that can be generated from it is methyl ester sulfonate (MES). This bio-based surfactant can reduce the interfacial tension (IFT) between oil and water. To produce a bio-based polymeric surfactant, sulfonate groups from MES were grafted onto polymer chains. Palm oil methyl ester was reacted with sulfuric acid (H2SO4) to synthesize MES. Afterwards, MES was reacted with the Ethyl Acrylate (EA) monomer to synthesize polymeric surfactant. Investigating this route to produce a bio-based polymeric surfactant has become the novelty of this study. This study showed that the best polymerization result was obtained at a mole ratio of MES to EA (1:0.5) with the highest viscosity of 14.47 mm2/s. The critical micelle concentration (CMC) analysis showed 0.5% at a mole ratio of MES to EA (1:0.5) which corresponded to the lowest interfacial tension (IFT) of 1.95 x 10-3 mN/m. Meanwhile, the contact angle gradually decreased from 58.44 to 11.79°. The polymeric surfactant, furthermore, was analyzed using FTIR and H-NMR and successfully confirmed the formation of bio-based polymeric surfactant. The core flooding experiment found that approximately 16.57% of oil could be recovered. The results of the study revealed a good potential of the polymeric surfactant to be applied in chemical enhanced oil recovery (CEOR).

Synthesis of silver (Ag) nano/micro-particles via green process using Andrographis paniculata leaf extract as a bio-reducing agent Chafidz, Achmad; Rusdi, Suharno; Nurrahman, Imam; Haryanto; Kalista Wibowo, Agam Duma; Kusmayadi, Adi; Hartanto, Danang Tri
Communications in Science and Technology Vol 9 No 1 (2024)
Publisher : Komunitas Ilmuwan dan Profesional Muslim Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21924/cst.9.1.2024.1450

In this work silver nano/micro-particles have been synthesized using sambiloto (Andrographis paniculata) plant extract as a bio-reducing agent. The effects of different plant extract concentrations, AgNO3 precursor concentrations, and reaction time on the synthesized silver nano/micro-particles were investigated. The silver nano/micro-particles samples were then analyzed using UV-Vis spectrophotometer (UV-Vis), X-Ray Diffractometer (XRD), Field Emission Scanning Electron Microscopy (FESEM), Particle Size Analyzer (PSA), and Fourier Transform Infra-Red (FTIR) spectroscopy. The UV-Vis absorbance spectrum of the colloid silver nano/micro-particles exhibited that all samples had absorbance peaks at a wavelength around 450 nm, confirming the formation of silver nano/micro-particles. It was also found that the UV-Vis absorbance peak of the silver nano/micro-particles inversely increased with decreasing AgNO3 solution concentration. Whereas, the higher the sambiloto extract concentration the higher the UV-Vis absorbance peaks. The UV-Vis absorbance peak increased with increasing synthesis time, suggesting that silver nano/micro-particles became more prominent. The UV-Vis absorbance peaks of the silver nano/micro-particles were about 0.0462, 0.0637, 0.0729, and 0.0936 at reaction time of 5, 10, 20, and 40 min, respectively. The XRD analysis result confirmed that the synthesized silver nano/micro-particles were in the form of nanocrystals with a face-centered cubic centered without any impurities. Additionally, the FESEM images showed that the silver nano/micro-particles had the primary particle size of 150-300 nm. There was the formation of some secondary particles with the size of about 0.7-1.5?m due to the agglomeration of primary particles. The particle size distribution analysis further confirmed the presence of primary and secondary particles. Meanwhile, the FTIR analysis confirmed the presence of four main peaks, linked to functional groups in the sambiloto extract and involved in the creation of silver nano/micro-particles.

Co-Authors Afandi, Amira Rahmani Agam Duma Kalista Wibowo Agung Ari Wibowo Alatas, Mukhsin Moh Aniek Sri Handayani Bayu Triwibowo Cahyani, Novia Noor Dewi Selvia Fardhyanti Dhoni Hartanto Elnaufal, Wildan Denly Fardhyanti , Dewi Selvia Hadikawuryan, Danang Subarkah Haniif Prasetiawan Hapsari, Anindita Ratih Hartanto, Danang Tri HARYANTO Hidayat, Pratikno Indri, Silvi Nurukma Jauhary, Thonthowy Joelianingsih Junaedi, Harri Kalista Wibowo, Agam Duma Khoiroh, Ianatul Kistriyani, Lilis Kusmayadi, Adi Latief, Fahamsyah H. Lestari, Ajeng Yulianti Dwi Maftukhaturrizqiyah, Maftukhaturrizqiyah Maharani Dewi Solikhah, Maharani Dewi Megawati, Rizki Mujtahid Kaavessina, Mujtahid Mulyono, Sarwono Nurrahman, Imam Pradnya, Irene Nindita Prasetiawan , Haniif Prima Astuti Handayani Purwana, Yulian Candra Putri, Erika Wahyu Ratna Dewi Kusumaningtyas Ria Wulansarie, Ria Riza Mazidu Sholihin Rosa, Bunga Mela Rusdi, Suharno Setyaningrum, Vilia Kartika Sinta Andriyani Suhartono, Jono Sumarno . Triwibowo , Bayu Ulviana, Ria Umi Cholifah Wara Dyah Pita Rengga Widi Astuti Wijayanti, Reni Titis Wulansari, Durroti Zuhriah Zainus Salimin

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