Papers by mardiyah kurniasih
Case Studies in Chemical and Environmental Engineering, 2025
Coal fly ash (FA) waste from local thermal power plant has been modified by acid activation and S... more Coal fly ash (FA) waste from local thermal power plant has been modified by acid activation and SiO2 enrichment using hydrochloric and acetic acids. The modified FA with acid activation (FAA_HAc and FAA_HCl) and SiO2 enrichment (SiO2_HCl and SiO2_HAc) were applied in the adsorption of methylene blue (MB) from aqueous solution. The physicochemical and morphological characteristics of the modified FA were characterized by XRF, SEM-EDX, XRD, BET, and TGA. The adsorption study was carried out in a batch system by optimizing pH, adsorbent dosage, contact time, initial dye concentration and temperature. The optimum adsorption is achieved at pH 8.0, adsorbent dosage of 1.5 g/L and contact time of 75 min. The experimental data fits the pseudo-secondorder models and the activation energies (Ea) are 48.71, 48.95, 32.26, and 30.61 kJ mol- 1 for FAA_HAc, FAA_HCl, SiO2_HAc, and SiO2_HCl, respectively. Langmuir, Freundlich, or Temkin isotherm models described well the experimental data. The qm values increase with temperature, indicating endothermic adsorption process. Themodynamic study gives the positive value of enthalpy (ΔH◦) and entropy (ΔS◦), and the negative value of free energy (ΔG◦) changes, suggesting an endothermic and spontaneous process. The lower activation energy and higher adsorption capacity of modified FA with a simple, low-cost and eco-friendly technique provide a prospective application of the adsorbents for the removal of dye waste from aqueous solution.
VIII INTERNATIONAL ANNUAL CONFERENCE “INDUSTRIAL TECHNOLOGIES AND ENGINEERING” (ICITE 2021)
Proceedings of the Soedirman International Conference on Mathematics and Applied Sciences (SICOMAS 2021)
Jurnal Kimia Valensi, 2021
Urease is a biocatalyst that serves to hydrolyze urea into ammonia and carbon dioxide. Since it i... more Urease is a biocatalyst that serves to hydrolyze urea into ammonia and carbon dioxide. Since it is an imported product, the price of urea is still high. Urease can be found in grains. One of the grains that has not been explored for its urease content is durian (Durio zibethinus L.) seeds. This study aims to determine the effect of germination time on the activity of urease from durian seeds and its characteristics including the effect of pH, incubation temperature, enzymatic reaction time, addition of EDTA and metals, and storage time on the activity of urease from durian seeds. The first step of this study was seed germination which was carried out in the dark for 0, 3, 5, 7, and 9 days. Durian seed sprouts were extracted by mashing them using a mortar and pestle. They were then homogenized using a stirrer and centrifuged in a cold state. The crude urease extract obtained was then tested for its activity using the Nessler method. The acquired data was tested statistically using AN...
Pemberian pelatihan terhadap kelompok PKK adalah salah satu bentuk kepedulian kepada para perempu... more Pemberian pelatihan terhadap kelompok PKK adalah salah satu bentuk kepedulian kepada para perempuan. Telah dilakukan kegiatan pelatihan yang diikuti ibu-ibu PKK RT 1 RW 3 desa Karangsari dalam upaya peningkatan pengetahuan dan ketrampilan. Pelatihan yang dilakukan meliputi pembuatan pewangi laundry dan penetapan harga produk. Setelah pelatihan tumbuh motivasi Ibu-ibu PKK untuk mengembangkan usaha pewangi laundry sehingga dapat meningkatkan pendapatan keluarga. Pendampingan dalam pengembangan usaha pewangi laundry juga dilakukan. Secara keseluruhan kegiatan pendampingan kelompok PKK desa Karangsari telah berjalan dengan baik. Indikator keberhasilan kegiatan ini dilihat dari kenaikan nilai pretest dan postest dari Ibu-ibu setelah mengikuti kegiatan. Selain itu juga dilihat dari berjalannya home industri pewangi laundry yang dimotori oleh Ibu-ibu PKK RT 1 RW 3 desa Karangsari. [Providing training to PKK groups is a form of caring for women. Training activities have been carried out by ...
Molekul, 2007
Determination of natural zeolite and activated natural zeolite acidity using gravimetric, titrati... more Determination of natural zeolite and activated natural zeolite acidity using gravimetric, titration and FTIR methods had been carried out. The result of gravimetric method show that the acidity of the natural zeolite and activated natural zeolite was 2,350 and 5,628 mol/gram, respectively. The titration method can be obtained that the acidity degree of the natural zeolite and activated natural zeolite was 12,333 and 12,067, respectively. The result showed that the activation of the natural zeolite sample by HCl caused dealumination.
Molekul, 2009
Chitosan is the N-deacetylated derivative of chitin. Chitosan is biodegradable, biocompatible and... more Chitosan is the N-deacetylated derivative of chitin. Chitosan is biodegradable, biocompatible and non-toxic. Chitosan is polycationic in acidic media and give antibacterial activity. In this paper, antibacterial activity of chitosan have been studied.Chitosan had been isolated from white shrimp. Antibacterial activity of chitosan solutions was examined against S. aureus The result showed that antimicrobial effect on S. aureus was strengthened as the choitosan concentrate decreased.
Molekul, 2016
A research on optimizing conditions to cholesterol adsorbed have been performed. Optimization was... more A research on optimizing conditions to cholesterol adsorbed have been performed. Optimization was performed by varying: contact time, adsorbent weight and temperature of the system's. A full factorial experimental design was used in this study. Characterization performed on the synthesized chitosan and carboxymethyl chitosan including FTIR, water content, ash content, solubility, porosity, and swelling effect. The results showed that carboxymethyl chitosan able to adsorb cholesterol under conditions optimal adsorbent with cholesterol ratio (1:200) with a contact time of 90 minutes at temperature of 40 °C. Meanwhile, at a temperature of 55 °C carboxymethyl chitosan capable of adsorb cholesterol under conditions optimal adsorbent with cholesterol ratio (1:300) with a contact time of 30 minutes. Chitosan and carboxymethyl chitosan synthesized has a water content of 7.4 and 10.2%, ash content of 0.14 and 2.29%, solubility in distilled water at 1.10-5and 1.98.10-3%, solubility in ace...
abstrak Biopolimer kitosan memiliki kemampuan adsorpsi terhadap zat warna dikarenakan adanya gugu... more abstrak Biopolimer kitosan memiliki kemampuan adsorpsi terhadap zat warna dikarenakan adanya gugus fungsi amino dan hidroksil. Penelitian ini bertujuan untuk mensintesis kitosan dan beads kitosan kulit udang jerbung, dan diuji kemampuan adsorpsinya terhadap zat warna rhodamin B. Karakterisasi kitosan dan kitosan beads hasil sintesis dilakukan menggunakan Fourier Transform Infra-Red Spectrophotometer (FTIR) dan ditentukan kadar air, kadar abu, serta swelling effect. Uji kemampuan adsorpsi kitosan dan kitosan beads terhadap rhodamin B menggunakan parameter: panjang gelombang maksimum, pengaruh pH dan variasi waktu kontak. Hasil penelitian menunjukkan bahwa hasil sintesis merupakan kitosan dan beads kitosan dengan kadar air sebesar 4,45% dan 6,84%, kadar abu sebesar 0,1% dan 2,83%, dan swelling effect 143,43% dan 94,05%. Kitosan dan beads kitosan dapat mengadsorpsi rhodamin B secara optimum masing-masing pada pH 4 dan 3 dengan waktu kontak 120 menit dan 180 menit dengan panjang gelomba...
Journal of Physics: Conference Series
Enzyme immobilizations were widely used to increase their shelf life which is essential for the w... more Enzyme immobilizations were widely used to increase their shelf life which is essential for the world’s industries. Therefore, amylase immobilized using Na-alginate as a matrix is necessary optimized and characterized. The parameters measured in the optimization of immobilization are the determination of the concentration of sodium alginate and contact time. Characterizations were conducted to determine the optimum concentration of substrate, the value Vmax, Michaelis-Menten constant (KM), pH, temperature, incubation time, and test reuse. The process of immobilized amylase activity test was performed in a continuous flow system using a reactor, and its sugar levels were determined using the Dinitro Salisilat Method (DNS). The results reveal that the immobilized amylase commercial has optimum concentration of Na-alginate of 5% (w/v) and contact time of 90 minutes with an immobilization efficiency value of 43.02%. Furthermore, the immobilized amylase has optimum activity at substrate ...
Soap is obtained from the reaction of fatty acid with alkali. The properties of soap depend on th... more Soap is obtained from the reaction of fatty acid with alkali. The properties of soap depend on the composition of fatty acids that are used. Each type of oil available in the market has its own composition. This study was aimed to produce solid soaps from four types of oils that are: olive oil, vco, palm oil and combination of all the three oils. Solid soap was obtained by reacting each of the oils with NaOH 30% and additives consist of dyes, fragrances and 1.5% of carboxymethyl chitosan. The solid soap resulted was characterized based on sni-06-3532-1994. The characteristics parameters determined were the moisture content, the number of free-alkali as NaOH or free fatty acid, non-saponified fat, and the amount of fatty acid and mineral oil. The characterization were also measured the pH. value and the foam stability. The result shows that the characteristics of the soap from four types of oils have met the SNI standard except for the water content of soap from the oil mixture. Howe...
N-metil kitosan merupakan derivat kitosan. Muatan polikationik N-metil kitosan dapat bereaksi den... more N-metil kitosan merupakan derivat kitosan. Muatan polikationik N-metil kitosan dapat bereaksi dengan muatan negatif seperti kolesterol. Penelitian ini bertujuan untuk sintesis N-metil kitosan dan mempelajari adsorpsi kolesterol oleh N-metil kitosan. Dalam penelitian ini telah dilakukan sintesis N-metil kitosan dari kitosan yang memiliki derajat deasetilasi sebesar 95% melalui mekanisme reduktif aminasi. Berdasarkan hasil sintesis diperoleh N-metil kitosan dengan kadar air sebesar 5,17%, bobot molekul 130.106,8 g/mol, dan indeks swelling 495,039%. N-metil kitosan kemudian diuji kemampuan adsorpsinya terhadap kolesterol . Studi adsorpsi berupa kinetika dan isoterm adsorpsi juga telah dilakukan. Berdasarkan hasil penelitian, adsorpsi kolesterol menggunakan N-metil kitosan mengikuti model adsorpsi isoterm Freundlich yang menunjukkan bahwa adsorpsi terjadi pada sistem yang heterogen dan lapisan adsorpsi yang terbentuk bersifat multilayer. N-metil kitosan memiliki kemampuan adsorpsi terha...
Karboksimetil kitosan merupakan derivate dari kitosan yang diperoleh melalui proses eterifikasi a... more Karboksimetil kitosan merupakan derivate dari kitosan yang diperoleh melalui proses eterifikasi alkalis kitosan dengan asam monokloroasetat. Kitosan diperoleh dari deasetilasi kitin dalam kulit udang putih (Penaeus vannamei). Keberadaan kitin dalam kulit udang tidak dalam keadaan bebas, akan tetapi berikatan dengan protein, mineral, dan berbagai macam pigmen (zat warna). Tujuan penelitian ini adalah untuk mensintesis dan mengkarakterisasi karboksimetil kitosan. Berdasarkan hasil penelitian diperoleh kitosan sebanyak 17,33% (per berat serbuk kulit udang) dan karboksimetil kitosan sebanyak 42% (per berat kitosan). Spektum IR karboksimetil kitosan menunjukan melebarnya serapan dari vibrasi ulur gugus -OH yang tumpang tindih dengan serapan vibrasi ulur –NH serta semakin tajamnya intensitas serapan pita ulur C=O dan vibrasi ulur C-O. Kadar air dari kitosan hasil sintesis sebesar 2,13% sedangkan karboksimetil kitosan sebesar 11,86%. Kadar abu kitosan hasil sintesis sebesar 0,73%, sedangka...
Bakso merupakan produk olahan yang mudah rusak karena mengandung kadar protein dan kadar air yang... more Bakso merupakan produk olahan yang mudah rusak karena mengandung kadar protein dan kadar air yang tinggi. Oleh katena itu, diperlukan pengawet seperti karboksimetil kitosan yang mempunyai gugus aktif yang mampu menghambat pertumbuhan mikroba. Tujuan diadakan penelitian ini adalah untukmensintesis karboksimetil kitosan yang kemudian diaplikasikan untuk memperpanjang daya tahan bakso. Karboksimetil kitosan adalah turunan kitosan yang diperoleh melalui proses eterifikasi alkalis dengan asam monokloroasetat pada suhu 80°C. Prosedur penelitian dibagi dalam lima tahap yaitu sintesis kitosan dan karboksimetil kitosan, karakterisasi hasil sintesis, aplikasi penambahankarboksimetil kitosan sebagai bahan pengawet bakso sapi dan analisis bakso terlapisi karboksimetil kitosan. Hasil penelitian menunjukkan proses eterifikasi kitosan dengan asam monokloroasetat dapat menghasilkan karboksimetil kitosan sebanyak 36,19% (b/b). Karakterisasi dari karboksimetil kitosan yang meliputi kadar air, kadar a...
Malaysian Journal of Fundamental and Applied Sciences, Nov 12, 2014
A research on optimizing the synthesis conditionsto obtaincarboxymethyl chitosan with the highest... more A research on optimizing the synthesis conditionsto obtaincarboxymethyl chitosan with the highest solubility in 1%(v/v) acetic acid as a solvent have been performed. Optimization was performed by varying: the concentration of NaOH during alkalizing the chitosan, chitosan: monochloroacetic acidratio, temperature and reaction time. This study uses a full factorial experimental design. The results showed that the highest solubility was found in 40% (w/v) NaOH concentration, chitosan to monochloroacetic acid ratio of 1:7, reaction temperature of 80°C and reaction time at 4 hours with the solubility up to 63.78 mg /mL.The IR and NMR (1 H and 13 C) spectra confirmed the success of the synthesis. The results of water content, ash content, molecular weight and swelling effect of carboxymethyl chitosan at the highest solubility were 14.27%, 8.48%, 2.8678 x 10 5 g/mol and 884.19%, respectively.
Jurnal Rekayasa Kimia & Lingkungan, Nov 19, 2018
Kitosan adalah polisakarida alami. Kitosan memiliki gugus amino dan hidroksi sehingga memungkinka... more Kitosan adalah polisakarida alami. Kitosan memiliki gugus amino dan hidroksi sehingga memungkinkan untuk memodifikasi kitosan secara kimia. Modifikasi kitosan dengan agen crosslinker dapat meningkatkan kapasitas adsorpsinya. Tripolifosfat merupakan agen crosslinker yang non toksik. Kitosan bersifat polikationik dan tripolifosfat bersifat polianionik sehingga dapat berinteraksi membentuk crosslink kitosan tripolifosfat. Tujuan dari penelitian ini yaitu mensintesis crosslink kitosan tripolifosfat dan studi adsorpsi ion Ni(II). Kitosan diperoleh dari deasetilasi kitin. Crosslink kitosan tripolifosfat disintesis dengan mereaksikan larutan kitosan dan larutan sodium tripolifosfat pH 3. Studi adsorpsi ion Ni(II) menggunakan crosslink kitosan tripolifosfat dilakukan pada variasi pH, waktu kontak dan perbandingan adsorben dan adsorbat. Variasi perbandingan adsorben dan adsorbat pada larutan Ni(II) digunakan untuk kajian adsorpsi isotermal. Hasil analisis menggunakan FTIR menunjukkan serapan pada daerah bilangan gelombang 1535,34 cm-1 yang menandakan adanya interaksi ion ammonium dan ion fosfat. Pada pH 10, waktu kontak 80 menit, suhu 28 o C dan perbandingan crosslink kitosan tripolifosfat : larutan Ni (II) 100 ppm sebesar 1:200 (g/mL), crosslink kitosan tripolifosfat dapat menurunkan ion Ni(II) sebanyak 50,536 % dengan kapasitas adsorpsi 8,205 mg/g dan mengikuti pola adsorpsi isotermal Freundlich.
IOP Conference Series: Materials Science and Engineering
The silver orthophosphate was successfully synthesized using the starting materials of AgNO3, KH2... more The silver orthophosphate was successfully synthesized using the starting materials of AgNO3, KH2PO4 under water and dimethyl sulfoxide (DMSO) solvents. The variation of DMSO in water was designed at 0, 5, 10, 15, 20 and 100% (v/v). The products were characterized by XRD, DRS, and SEM. The photocatalytic properties were evaluated under the blue light irradiation using the methyl orange degradation. The results showed that the DMSO significantly affected the morphology, particle size and bandgap energy of Ag3PO4. The addition of DMSO decreased the particle size of Ag3PO4 and changed the tetrahedron into an irregular shape. The bandgap energies of 2.33, 2.28 and 2.42 eV were observed in the sample prepared with the content of DMSO at 0, 15 and 100% respectively. The highest photocatalytic activity was found at 15% DMSO. This excellent photocatalytic activity might be due to the lower bandgap energy and the higher intensity ratio of [222]/[110] facet.
The Journal of Pure and Applied Chemistry Research
Carboxymethyl chitosan has antimicrobial activity. The solubility of carboxymethyl chitosan makes... more Carboxymethyl chitosan has antimicrobial activity. The solubility of carboxymethyl chitosan makes it easy to apply as a food preservative. Sausage is a processed product of meat, and it is classified as perishable food. The purpose of this study was to synthesize carboxymethyl chitosan, investigate the microbiological quality and shelf-life of homemade sausage treated with carboxymethyl chitosan. Carboxymethyl chitosan was obtained through the process of carboxymethylation of alkaline chitosan with monochloroacetic acid. Chitosan in the study was synthesized from shrimp skin. Sausages treated with carboxymethyl chitosan then measured water content, ash content, TPC (Total Plate Count) and organoleptic values for four consecutive days. The results showed that carboxymethyl chitosan could extend the shelf life of sausages both stored at room temperature or cold temperatures.
International journal of biological macromolecules, Jan 12, 2018
Chitosan is a biopolymer that has antifungal activity against C. albicans. Chemical modification ... more Chitosan is a biopolymer that has antifungal activity against C. albicans. Chemical modification of chitosan can provide it with new functional properties for a wide range of biological and biomedical applications. Carboxymethyl chitosan is a derivative of chitosan obtained by etherification of alkaline chitosan with monochloroacetic acid. Carboxymethyl chitosan has a higher solubility than chitosan; therefore it is more readily applicable for use in various fields. Chitosan also has antifungal activity against C. albicans. This study evaluated carboxymethyl chitosan as a gauze-coating material to be used for its antifungal properties. This study also optimized the coating process. Gauze was coated with carboxymethyl chitosan then characterized by Fourier Transform Infra-Red Spectrophotometer (FTIR), X-ray diffraction and scanning electron microscopy (SEM). The antifungal activities of gauze-coated samples were then tested by the diffusion method. The results show that the optimum c...
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Papers by mardiyah kurniasih