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Jaya Hardi
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Program Studi Kimia Fakultas MIPA, Uniiversitas Tadulako Jl. Soekarno-Hatta Km. 9, Tondo Palu, 94117
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INDONESIA
KOVALEN: Jurnal Riset Kimia
Published by Universitas Tadulako
ISSN : -     EISSN : 24775398     DOI : https://doi.org/10.22487/kovalen
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry
KOVALEN: Jurnal Riset Kimia is a peer-reviewed journal of chemistry published by the Tadulako University, Indonesia. This journal concern with publishing the original research articles, review articles, and the current issues related to chemistry. Publishing frequency 3 issues per year, in April, August, and December.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 325 Documents
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KAJIAN AKTIVASI ARANG AKTIF BIJI ASAM JAWA (Tamarindus indica Linn.) MENGGUNAKAN AKTIVATOR H3PO4 PADA PENYERAPAN LOGAM TIMBAL Serli Jayanti; Ni Ketut Sumarni; Musafira Musafira
KOVALEN: Jurnal Riset Kimia Vol. 1 No. 1 (2015)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

ABSTRAK Penelitian tentang penyerapan logam Pb menggunakan biji asam sebagai adsorbat telah dilakukan. Metode yang digunakan dalam penelitian ini adalah aktivasi karbon dengan H3PO4 sebagai aktivator. Hal itu dilakukan dengan menerapkan 5 variasi berat ( 1, 2, 3, 4, dan 5 g) dan konsentrasi (1, 2, 3, 4, dan 5 N ). Untuk melihat penyerapani Pb terhadap waktu kontak, maka 5 variasi waktu kontak telah diterapkan yaitu dari 10, 20, 30, 40, dan 50 menit. Hasil penelitian menunjukkan bahwa karbon aktif mempunyai kapasitas adsorpsi terbaik (89,59 ppm) pada berat 5 gram , sementara waktu kontak optimum dicapai pada 50 menit dengan 69,02 ppm dari Pb yang terserap. Aktivasi karbon aktif dengan H3PO4 pada konsentrasi optimum  2 N telah meningkatkan kapasitas adsorpsi sebesar 11,11%.                                            Katakunci : Absorben, Biji Asam Jawa, Karbon Aktif.
KAJIAN KADAR FENOLAT DAN MUTU ORGANOLEPTIK BUBUR INSTAN DARI UBI BANGGAI JENIS BAKU MAKULOLONG (Discoreabulbifera var celebica bukill) DAN BAKU PUKUS (Discorea of alata) Sri Adeningsih; Syaiful Bahri; Nurhaeni Nurhaeni
KOVALEN: Jurnal Riset Kimia Vol. 1 No. 1 (2015)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

ABSTRAK Penelitian mengenai “Kajian Kadar Fenolat dan Mutu Organoleptik Bubur Instan dari Ubi Banggai Jenis Baku Makulolong (DiscoreaBulbifera Var Celebica Bukill) Dan Baku Pukus (Discorea Of Alata.)telah dilakukan. Penelitian ini bertujuan untuk mengetahui kadar fenolat kedua jenis ubi Banggai tersebut sebelum dan sesudah diolah menjadi bubur instan dan mutu organoleptiknya. Hasil penelitian diperoleh adalahBaku Makulolong basah (hasil glatinasi) memiliki kadar fenolat  2,381 % dan Baku Pukus basah (hasil glatinasi) memiliki kadar fenolat 2,162 %. Sedangkan saat kering (hasil glatinasi) memiliki kadar fenolat 1,638 % dan 1,395 %. Kadar fenolat yang terkandung pada buburBaku makulolong  1,852 % dan kadar fenolat yang terkandung pada bubur Baku Pukus 1,671 %. Dari hasil uji mutu organoleptik  pada parameter rasa, aroma dan tekstur menunjukkan bahwa tidak ada perbedaan yang nyata antara bubur instan Baku Pukus dengan bubur instan Baku Makulolong. Sedangkanpada parameterwarnamenunjukkanadanya perbedaan nyata antara warna bubur instan Baku Pukus dengan bubur instan Baku Makulolong. Kata Kunci : Fenolat, mutu organoleptik, bubur instan, ubi Banggai
KAJIAN DAYA SERAP ARANG TEMPURUNG KEMIRI (Aleorites Moluccana) TERHADAP ION BESI (III) DAN ION TIMBAL (II) PADA BERBAGAI WAKTU KONTAK Yuniar Yuniar; Mappiratu Mappiratu; Nurhaeni Nurhaeni
KOVALEN: Jurnal Riset Kimia Vol. 1 No. 1 (2015)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

ABSTRAK Telah dilakukan penelitian Kajian Daya Serap Arang Tempurung Kemiri (Aleorites Moluccana) Terhadap Ion Besi (III) dan Ion Timbal (II) pada Berbagai Waktu Kontak. Penelitian ini bertujuan untuk mengetahui waktu kontak antara ion logam berat dengan arang tempurung kemiri yang menghasilkan daya serap tinggi. Waktu kontak yang digunakan adalah 10, 20, 30, 40 dan 50 menit. Waktu kontak yang terbaik pada logam Fe adalah 40 menit dan  pada logam Pb adalah 50 menit.  Hasil yang di peroleh menunjukkan bahwa semakin lama waktu kontak maka semakin banyak ion logam terserap. Kata kunci : Daya serap, Arang tempurung kemiri, Waktu kontak
DERAJAT DEASETILASI KITOSAN DARI CANGKANG KERANG DARAH DENGAN PENAMBAHAN NaOH SECARA BERTAHAP Syaiful Bahri; Erwin Abd. Rahim; Syarifuddin Syarifuddin
KOVALEN: Jurnal Riset Kimia Vol. 1 No. 1 (2015)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

The study about raising of chitosan deacetilation degree in Anadara granosa by gradually adding NaOH has been done. The aim of the research was to study the influence of gradually added NaOH on the raising of chitosan deacetilation. The degree of chitosan deacetilation was determined by using spectroscopy of Fourier Transform Infra Red (FTIR). The result showed that the deacetilation degree increase with the increase of NaOH added i.e 79%; 85,9%; 89,95% for the first, the second and the third addition of NaOH with 3, 6 and 9 hours of the reaction the respectively. Keywords: Anadaragranosa; Chitin; Deacetilation Degree; Chitosan
PENGARUH WAKTU PROSES DEASETILASI KITIN DARI CANGKANG BEKICOT (Achatina fulica) TERHADAP DERAJAT DEASETILASI Wahyuni Wahyuni; Ahmad Ridhay; Nurakhirawati Nurakhirawati
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 1 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

ABSTRACT Research on the effect of chitin deacetylation processing times from shells of snails on the degree of deacetylation has conducted with a variations of 60 minutes, 90 minutes, 120 minutes and 150 minutes. The purpose of this study was to determine the effect of times improvement in the chitin deacetylation process of the degree of deacetylation. The degree of deacetylation is determined using Fourier Transform Infrared spectroscopy (FTIR). The results show the degree of deacetylation increases with the length of time the process of deacetylation that is 60 minutes to produce the degree of deacetylation of 55.6%, a degree of deacetylation of 90 minutes produces 62.4%, 120 minutes produces 70.3% degree of deacetylation, and time 150 minutes to produce the degree of deacetylation of 84.3%. So that, the length of time spent on the process of deacetylation of chitin from a snail shells, can increase the degree of deacetylation. Keywords: Snail Shells, Times, Degree of Deacetylation, Chitin, Chitosan
BIOSORPSI Hg(II) DENGAN KULIT BUAH KAKAO (Theobroma cacao L.) Fitri Fitri; Syaiful Bahri; Nurakhirawati Nurakhirawati
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 1 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

ABSTRACT This study aims are determine the amount of biosorbent from cocoa fruit skin and required best interaction time to be able to adsorb Hg(II) in solution. This study was conducted using a completely randomized design (CRD) with 5 variations of biosorbent amount is 2, 4, 6, 8, and 10 grams and contact time is 30, 60, 90, 120, 150 minutes. Each treatment was repeated twice. The results showed that the best amount of biosorbent in the adsorption of Hg(II) is 99.11% with biosorbent weight 2 grams. Best contact time for the adsorption of Hg(II) is 90 minutes with the amount of adsorbed as much as 99.82%. Keywords : Biosorption, Cocoa fruit skin, Mercury
PEMANFAATAN KITOSAN CANGKANG KEONG BAKAU (Telescopium sp) SEBAGAI PENGIKAT ION LOGAM TIMBAL (Pb) DALAM LARUTAN Darman Panggalo; Syaiful Bahri; Ni Ketut Sumarni
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 1 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

ABSTRACTResearch utilization of mangrove snail chitosan conech shell (Telescopium sp) as a binding metal ions of lead (Pb) in solution. This study aims to determine the best time of the metal ion absorption of lead (Pb) by a conch shell chitosan mangrove (Telescopium sp) with the remains of 150 rpm shaking method. This research was conducted by completely randomized design (CRD) and 4 variations of shaking time is 50, 55, 60 and 65 minutes. Each treatment was repeated three times. The results obtained are binding Pb (II) by the highest chitosan during 65 minutes agitation is 98.27%. Key words: Chitosan, absorption, lead
PENGGUNAAN BERBAGAI TEKANAN DAN WAKTU HIDROLISIS PADA PRODUKSI GLUKOSAMIN HIDROKLORIDA DARI KITOSAN CANGKANG BEKICOT (Achatina fulica) Noviana Linawati Dewi; Syaiful Bahri; Jaya Hardi
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 1 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

ABSTRACT This study aims to determine the effect of pressure and time hydrolysis to produce glucosamine hydrochloride with the highest yield and the best quality of the chitosan of a snail shell. The study used a completely randomized design (CRD) factorial design consisting of 2 factors with 5 variations of hydrolysis time (40; 50; 60; 70 and 80) minutes and 2 variations of pressure (1 atm and 2 atm). Each treatment is done twice so obtained 20 experimental units. The highest glucosamine hydrochloride was obtained in hydrolysis time of 80 minutes and a pressure of 1 atm. Yield of 7,54%. Test of solubility in distilled water at 20°C was obtained of 3,79. Mol/L, while the maximum absorption of the UV-Vis with the addition of reagent Schales is at a wavelength of 420 nm. Keywords: Snails, Chitosan, Glucosamine, Hydrolysis Time, Pressure
OPTIMALISASI PRODUKSI SEMI REFINED CARAGINAN (SRC) DARI RUMPUT LAUT( Eucheuma cottonii) Moh. Rizal; Mappiratu Mappiratu; Abd. Rahman Razak
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 1 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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ABSTRACT The investigation about the optimization of SRC Production (semi refined caraginan) from Eucheuma cottonii has beendone. The study aim to find whether or not there is interaction beetween consentration KOH and cooking time on rendamen and SRC purity degree and to find at which consentration KOH and cooking time yield the highest SRC Purity  degree. It was done by applying completely randomized design (CRD) i. e factorial design. It was consist of 2 factors ( consentration KOH and cooking time ). Each factors consist of 3 levels and all of experiments where done in duplo, so the total there ware 18 experiments. The result showed that The highest Rendaman and the highset degree of piyurity were obsained at consentration KOH and cooking time were 8 % and 60 minutes respectively. The result were 33.83 and 59.243 % accordingly Keywords : Eucheuma cottonii, Extraction Semi Refined Carrageenan, KOH concentration, Long time of cooking
KAJIAN SINTESIS GIPSUM DARI BATU GAMPING ASAL SULAWESI TENGAH Gloria Yoanita; Mappiratu Mappiratu; Prismawiryanti Prismawiryanti
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 1 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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ABSTRACT Research has been done for synthesis gypsum from limestone in Central Sulawesi. This Research aims are to know the best ratio of sulphuric acid of limestone that producer the highest CaSO4 and which areas in the Central Sulawesi as a producer of best limestone for the raw materials CaSO4. Variation ratio of sulphuric acid used is 70:25, 80:25, 90:25, 100:25, and 110:25. This Research using a group randomized design (GRD). The treatment was applied variations from limestone on the 3 areas, that is limestone from Bangkep (group 1), limestone from Buol (group 2) and limestone from Donggala (group 3). The purity of CaSO4 be analiyzed using AAS and uv-vis Spectrofotometri. The result showed that the best ratio of sulphuric acid is 110:25 and producer area of the best limestone for the raw materials of CaSO4 in the Bangkep. Keywords: Gypsum, Limestone, Sulfuric Acid, Yield, Purity

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