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Swelling Degree of Carrageenan-Corncob Bead Gel in Various Media Sperisa Distantina; Saktika Rofi'ah Haryani; Rif'ah Ulfatun Hasanah; Mujtahid Kaavessina
CHEMICA: Jurnal Teknik Kimia Vol 8, No 1 (2021): June 2021
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26555/chemica.v8i1.20133

Abstract

Bead hydrogels were prepared from carrageenan-corncob mixture by physically and chemically crosslinking. The aims are to investigate the effect of carrageenan-corncob weight ratio and glutaraldehyde crosslinking on the swelling degree properties. The mixture of various carrageenan-corncob weight ratio (1:2, 1:1, 2:1, and 1:0) was dropped into KCl and CaCl2 solution and then the obtained bead gels was dried. The dried bead gel was crosslinked using glutaraldehyde 4%. The swelling degree behavior of the bead gels were tested in distilled water, 0.1M NaCl, and synthetic urine. The bead gels based on the mixture of carrageenan-corncob exhibited the hydrogel property. The highest swelling degree is carrageenan-corncob bead gels in the ratio of 1:0. The highest swelling degree is found in the distilled water and the lowest is in the synthetic urine. The 4% glutaraldehyde crosslinking does not show specific different results for carrageenan-corncob bead gels.
Isotherm Adsorbsi Uap Air Komposit Poli(asam laktat) - Grafit Fadilah Fadilah; Mujtahid Kaavessina; Sperisa Distantina; Dwi Ardiana Setyawhardani; Endang Kwartiningsih; Aida Nur Ramadhani; Isa Fakhruddin; Amaldo Firjarahadi Tane
Equilibrium Journal of Chemical Engineering Vol 6, No 1 (2022): Volume 6, No 1 July 2022
Publisher : Program studi Teknik Kimia UNS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/equilibrium.v6i1.58786

Abstract

ABSTRAK. Poli asam laktat adalah polimer hidrofobik yang termasuk dalam kelas biomaterial yang bersifat biodegradable. Poli asam laktat berpotensi untuk dijadikan komposit polimer konduktif (conductive polymer composite - CPC) yang dipergunakan sebagai bahan semikonduktor dengan cara mencampurkan grafit kepadanya. Perilaku adsorpsi uap air perlu dipelajari untuk mengetahui stabilitas komposit dan ditunjukkan melalui kurva isotherm adsorpsi uap air. Tujuan dari penelitian ini adalah mempelajari isotherm adsorpsi uap air komposit poli asam laktat/grafit pada berbagai komposisi grafit. Pengamatan terhadap isotherm adsorpsi uap air dilakukan dengan metode gravimetri pada berbagai kondisi kelembaban relatif. Hasil yang diperoleh menunjukkan bahwa kurva isotherm mengikuti tipe II menurut kasifikasi Brunauer, yaitu kurva berbentuk sigmoidal.  Semakin tinggi kondisi kelembaban relatif, semakin besar kandungan air kesetimbangan. Peningkatan kandungan air kesetimbangan secara tajam terjadi pada kondisi kelembaban di atas 75%.  Semakin tinggi komposisi grafit, semakin besar kandungan uap air kesetimbangan. Data kesetimbangan dicocokkan dengan model kesetimbangan sorpsi uap air yaitu model Guggenhiem-Anderson-deBoer (GAB), model Peleg, dan model Oswin. Model GAB memberikan gambaran isotherm yang terbaik.Kata kunci: Adsorpsi Uap Air, Kesetimbangan, Komposit, Poli Asam Laktat/Grafit, Pemodelan  ABSTRACT. Poly(lactic acid)/PLA is a hydrophobic polymer that belongs to the class of biodegradable biomaterial. PLA can be used as material in the manufacture of conductive polymer composite (CPC), which is used as a semiconductor material by mixing graphite into it. The water vapor adsorption behavior needs to be studied to determine the stability of the composite. This research aims to investigate the water vapor adsorption isotherm in poly(lactic acid)/graphite composites on various graphite compositions. The gravimetric method carried observations on the water vapor adsorption isotherm at various relative humidity conditions. The results obtained indicate that the isotherm curve follows type II according to the Brunauer classification. The higher the relative humidity, the greater the equilibrium water content. A sharp increase in the equilibrium water content occurs at humidity conditions above 75%. The higher the graphite composition, the greater the equilibrium moisture content. The Guggenhiem-Anderson-deBoer (GAB), Peleg, and Oswin sorption models were used to fit the experimental data. The GAB model best described the isotherms of the composites.Keywords: Composite, Equilibrium, Modeling, Poly(lactic acid)/Graphite, Water Vapor Adsorption
Matriks Pengontrol Pelepasan Urea Berbasis Karagenan: Pengaruh Konsentrasi Glutaraldehid Sperisa Distantina; Mujtahid Kaavessina; Fadilah Fadilah
Jurnal Teknik Kimia Indonesia Vol 18, No 1 (2019)
Publisher : ASOSIASI PENDIDIKAN TINGGI TEKNIK KIMIA INDONESIA (APTEKIM)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/jtki.2019.18.1.3

Abstract

Abstrak. Pada penelitian ini, matrik hidrogel berbasis karagenan dibuat dan diaplikasikan untuk mengontrol pelepasan urea. Tujuan penelitian ini adalah mempelajari pengaruh konsentrasi glutaraldehid terhadap kecepatan pelepasan urea dan menyusun model kecepatan pelepasan urea. Film karagenan dimodifikasi secara kimiawi menggunakan ikatan silang atau crosslinking dengan glutaraldehid. Larutan karagenan 7 g/100 mL dicetak menjadi lembaran dan kemudian dikeringkan sehingga diperoleh lapisan film. Film direndam dalam larutan glutaraldehid dengan konsentrasi tertentu selama 2 menit dan dilanjutkan dipanaskan pada suhu 110oC selama 20 menit. Film yang dihasilkan dicuci dengan etanol dan dikeringkan. Pengisian urea ke dalam matrik film menggunakan metode difusi. Film kering direndam dalam larutan urea 0,074 g/mL selama satu jam dan selanjutnya dikeringkan. Kecepatan pelepasan urea dari film ke dalam media air dievaluasi berdasarkan data konsentrasi urea dalam cairan sebagai fungsi waktu. Berdasarkan hasil penelitian didapatkan bahwa semakin besar konsentrasi glutaraldehid (1-5%) menyebabkan urea yang tersimpan di dalam film semakin rendah. Model matematika yang diusulkan dapat mewakili peristiwa pelepasan urea dari film. Film berbasis karagenan yang dihasilkan berpotensi sebagai matrik pengontrol pelepasan urea. Kata kunci: crosslinking, glutaraldehid, hidrogel, karagenan, urea. Abstract. Controlled Release Matrices of Urea from Carrageenan: Effect of Glutaraldehyde Concentration. In this study, carrageenan-based hydrogel matrices were prepared and applied for urea controlled release. The aim of this work was to study the effect of glutaraldehyde concentration on the rate of urea release in water. Carrageenan films were chemically modified by crosslinking with glutaraldehyde. The films were prepared by casting the aqueous carrageenan 7 g/100 mL and then followed by drying. The films obtained were immersed in certain glutaraldehyde concentration for 2 min and then heated in the oven at 110oC for 20 min. The crosslinked films were washed using ethanol and then air-dried until the weight is constant. The dried films were immersed in a urea solution (0.074g/ml) for 1 hr and then dried. The rate of urea release was determined by measuring the urea concentration in water as a function of time of release. Results showed that higher glutaraldehyde concentration (1–5%) produced films with less urea content. The proposed mathematic model of urea release from the film can represent the rate of urea release. The prepared carrageenan-based film has the potential for controlling of urea release. Keywords: carrageenan, crosslinking, glutaraldehyde, hydrogel, urea. Graphical Abstract
Pemanfaatan Cangkang Biji Nyamplung sebagai Penghasil Resin untuk Mengatasi Permasalahan Limbah Padat di CV Plantanesia Dwi Ardiana Setyawardhani; Mujtahid Kaavessina; Fadilah Fadilah; Sperisa Distantina; Endang Kwartiningsih; Yoseph Calasanctius Danarto; Aida Nur Ramadhani
Equilibrium Journal of Chemical Engineering Vol 6, No 2 (2022): Volume 6, No 2 December 2022
Publisher : Program studi Teknik Kimia UNS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/equilibrium.v6i2.66463

Abstract

ABSTRAK. CV Plantanesia merupakan industri penghasil minyak dari biji nyamplung (Calophyllum inophyllum) yang dikenal sebagai Tamanu oil. Minyak tersebut dijual sebagai bahan baku kosmetik untuk produk skin care dan obat tradisional seperti luka, penyakit kulit, rematik, minyak untuk urut maupun obat gatal. Produksi Tamanu oil menghasilkan limbah hasil pengepresan minyak dari bijinya yang berupa bungkil/ampas biji dan cangkang/kulit buah nyamplung. Limbah tersebut dihasilkan dalam jumlah besar dan belum dimanfaatkan sehingga hanya dibuang sebagai sampah dan dibakar. Cangkang biji nyamplung mengandung resin senyawa fenolik yang memiliki sifat antioksidan, anti inflamasi, anti kanker, dan anti mikroba sehingga dapat dimanfaatkan untuk pengobatan Tujuan pengabdian pada masyarakat ini adalah memberikan pelatihan pengolahan limbah pengepresan minyak biji nyamplung, khususnya cangkang biji dan pengolahannya untuk menjadi resin. Kegiatan ini dilakukan di CV. Plantanesia yang berlokasi di Tasikmadu, Kecamatan Jaten, Kabupaten Karanganyar. Pelatihan diberikan dalam bentuk penyuluhan, diskusi dan pelatihan pengambilan (ekstraksi) resin dari cangkang nyamplung. Proses ekstraksi resin dari cangkang nyamplung dan pengaturan kondisi optimal ekstraksi dilakukan terlebih dahulu melalui percobaan pendahuluan di Laboratorium Program Studi Teknik Kimia FT UNS. Hasil percobaan tersebut digunakan sebagai materi pelatihan. Penyampaian materi dilakukan melalui kunjungan, penyuluhan dan pelatihan pada pelaku usaha khususnya CV Plantanesia. Materi penyuluhan dikemas dalam modul dan dipraktekkan secara langsung di lokasi CV. Dari kegiatan ini, mitra memperoleh peningkatan wawasan akan pemanfaatan cangkang biji nyamplung. Produk resin yang dihasilkan diharapkan dapat bermanfaat sebagai produk samping yang bernilai jual tinggi untuk meningkatkan pendapatan bagi pelaku usaha, sekaligus dapat mengatasi masalah limbahnya. Kata kunci: cangkang biji nyamplung, resin, tamanu oilABSTRACT. CV Plantanesia is a home industry that produces nyamplung (Calophyllum inophyllum) seed oil known as Tamanu oil. The oil is usually used for skin care products and traditional medicines such as wounds, skin diseases, rheumatism, massage oil and itching medicine. Tamanu oil production leaves solid waste from the pressing process, which is cake/seed dregs and shells/skin of nyamplung fruit. This waste is generated in large quantities and has not been utilized, so it is only disposed of as garbage or just burned. Nyamplung seed shells contain resin phenolic compounds which is used as antioxidant, anti-inflammatory, anti-cancer and anti-microbial properties. It can be used for medical treatment. This project aims to provide training on processing waste nyamplung seed oil, especially the seed shells and their processing to become resin. This activity is carried out at CV. Plantanesia which is located in Tasikmadu, Jaten, Karanganyar. The project was implemented in various activities, such as counseling, focus group discussions and workshop for extracting resin from nyamplung shells. The resin extraction and optimization process condition were developed at the Chemical Engineering Laboratory, Faculty of Engineering, Sebelas Maret University. The experimental results are implemented in the workshop at the industry. From this activity, partners gain increased insight into the use of nyamplung seed shells. The resin product is expected to be useful as a high value by-product to increase the benefit of the industry, as well as to overcome the waste problem.Keywords: nyamplung seed shell, resin, tamanu oil