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All Journal KOVALEN: Jurnal Riset Kimia Chimica et Natura Acta Dalton : Jurnal Pendidikan Kimia dan Ilmu Kimia FLUIDA Kumawula: Jurnal Pengabdian Kepada Masyarakat Jurnal Teknik Kimia dan Lingkungan

Robby Sudarman

Jurusan Teknik Kimia, Politeknik Negeri Bandung

Author-ID : 2681106

Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Decision Sciences, Operations Research & Management Economics, Econometrics & Finance Education Energy Engineering Environmental Science Materials Science & Nanotechnology Social Sciences

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Articles

RANCANG BANGUN SISTEM PENGOLAHAN AIR JERNIH DI KAMPUNG WISATA SABLON Rony Pasonang Sihombing; Agustinus Ngatin; Joko Suryadi; Retno Dwi Jayanti; Yunus Tonapa Sarungu; Robby Sudarman
Kumawula: Jurnal Pengabdian Kepada Masyarakat Vol 5, No 1 (2022): Kumawula: Jurnal Pengabdian Kepada Masyarakat
Publisher : Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/kumawula.v5i1.35907

Air bersih yang memadai secara kuantitas, kualitas dan kontinuitas merupakan kebutuhan penting untuk kelangsungan hidup manusia. Oleh karenanya diperlukan suatu instalasi pengolahan air untuk menunjang kebutuhan ini. Air tanah merupakan air yang belum mengalami proses pengolahan dengan kriteria kualitas air yang sudah mendekati air bersih. Metode pengolahan air yang dilakukan menggunakan metode filtrasi fisik dan kimia sebelum digunakan untuk kebutuhan sehari-hari. Jenis filter yang digunakan adalah filter benang ukuran 10 µm, filter polipropilen (PP) 10 µm dan filter karbon aktif. Berdasarkan hasil rancangan, air yang dihasilkan pada sistem rancang bangun diantaranya adalah air dengan kualitas kesadahan 2.3 NTU, masa pakai filter benang 14 hari/bulan, filter PP 2.4 hari/bulan, dan filter karbon aktif 30 hari/bulan. Untuk kemudahan operasional, sistem rancang bangun untuk filter PP dibuat paralel 3 agar perawatan dapat dilakukan setiap minggu.

Pengaruh Konsentrasi Surfaktan Non-Ionik Terhadap Viskositas Perekat Polivinil Asetat Berbasis Air: Effect of Non-Ionic Surfactant on Water-Based Adhesive Viscosity Rony Pasonang Sihombing; Robby Sudarman; Agustinus Ngatin
KOVALEN: Jurnal Riset Kimia Vol. 6 No. 3 (2020): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2020.v6.i3.15278

Substrate combining could be done by using adhesive. In Indonesia, especially industrial field, solvent base adhesives were still being developed. This kind of adhesive was not environmental friendly and not safe handling. Therefore, Polyvinyl Acetate (PVAc) water-based adhesive was prepared as an outcome of this research as one of solution to overcome the problem above. Effect of surfactant concentration on the viscosity was aimed at this research. Semi continuous polymerization with stirring motor rates on 50 – 500 rpm was used (optional). Pressure of 1 atm, 750C temperature, 5 – 6 hours reaction time for each was used as polymerization operation in this research. Vinyl Acetate Monomer (VAM), partial hydrolysis Polyvinyl Alcohol (PVOH), water, Ammonium Persulfate (APS) were prepared as raw material. NP-10 and NP-06 were non-ionic surfactants which each concentration was varied in this research. Water-based adhesive with NP-06 concentration variation resulting in viscosity from 98 m.Pa for 0.17 %wt concentration to 213 m.Pa for 0.68 %wt concentration. While NP-10 concentration variation resulting viscosity from 143 m.Pa for 0.17 %wt to 321 m.Pa for 0.68 %wt concentration. Therefore, adhesive with NP-10 surfactant concentration variable has a higher viscosity rate than NP-06 ones. Keywords: Water-based adhesive, non-ionic surfactant, adhesive viscosity

PENGARUH KONSENTRASI GARAM TERHADAP VISKOSITAS SABUN CAIR BERBASIS SURFAKTAN ANIONIK Robby Sudarman; Alisya Nurbaits; Rony Pasonang Sihombing
Dalton : Jurnal Pendidikan Kimia dan Ilmu Kimia Vol 4, No 1 (2021): (Mei) Dalton : Jurnal Pendidikan Kimia dan Ilmu Kimia
Publisher : Universitas Islam Kalimantan MAB Banjarmasin

Sabun cair merupakan salah satu jenis pembersih yang cukup banyak digunakan di dalam aspek kehidupan. Material ini berfungsi sebagai bahan penghilang kotoran dan lemak pada berbagai perkakas. Tujuan dilaksanakannya penelitian ini adalah untuk dasar pengaturan viskositas sabun cair bagi penelitian-penelitian selanjutnya. Surfaktan Sodium Lauril Sulfat (SLS) digunakan sebagai bahan baku utama dan garam NaCl sebagai pengatur viskositas. Konsentrasi NaCl yang digunakan dalam penelitian ini dimulai dari 0.45 % wt hingga 2.2% wt. Metode yang digunakan adalah metode reaksi batch. Hasil penelitian menunjukkan terjadi peningkatan viskositas sabun cair dari 300 cps hingga 5000 cps. Oleh karenanya, pengaturan viskositas dapat dilakukan dengan menggunakan konsentrasi garam sesuai kebutuhan.

Penyisihan Kadar Amoniak dalam Limbah Cair Industri Pupuk Menggunakan Sequencing Batch Reactor Robby Sudarman; Herawati Budiastuti; Nancy Siti Djenar; Efniarsi S. Panggalo; Ajie Nurhasyim
Fluida Vol 13 No 2 (2020): FLUIDA
Publisher : Jurusan Teknik Kimia, Politeknik Negeri Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35313/fluida.v13i2.2264

ABSTRAK Sifat toksik nitrogen amoniak dalam limbah cair berbahaya bagi kehidupan sehingga perlu untuk dihilangkan. Pada penelitian ini penyisihan kadar amoniak yang tinggi dalam limbah cair industri pupuk dilakukan melalui proses nitrifikasi dan denitrifikasi menggunakan Sequencing Batch Reactor (SBR). Dua reaktor SBR digunakan dimana pada reaktor pertama (R1) dilakukan pengadukan dan pada reaktor kedua (R2) dilakukan aerasi. Hasil penelitian menunjukkan bahwa pada pembebanan 0,787 mg amoniak/L/hari dan Hydraulic Retention Time (HRT) 20 hari, efisiensi penyisihan kadar amoniak mampu dicapai pada kisaran 71,26%-90,91% (R1) dan 62,32% -92,21% (R2). Pengukuran pH pada HRT 20 hari berada pada rentang 8,25-8,65 pada R1 dan pH 8,34-8,73 pada R2. Pada HRT 15 hari, efisiensi penyisihan kadar amoniak efluen pada R1 menurun yaitu dari 90,89 % menjadi 86,81% dan pada R2 menurun dari 90,59% menjadi 40,99 %. Pada HRT 15 hari, efisiensi penyisihan kadar amoniak pada R1 lebih baik dibandingkan pada R2 yang disebabkan adanya penambahan aerasi pada R1 di akhir penelitian. Kata kunci: amoniak, limbah cair, industri pupuk, sequencing batch reactor ABSTRACT The toxic nature of ammonia nitrogen in liquid waste is dangerous for life, so it needs to be eliminated. In this study, the removal of high ammonia levels in the fertilizer industry wastewater was carried out through a process of nitrification and denitrification using the Sequencing Batch Reactor (SBR). Two SBR reactors were used where the first reactor (R1) was stirred and the second reactor (R2) was aerated. The results showed that at a load of 0.787 mg of ammonia/L/day and 20 days of Hydraulic Retention Time (HRT), the efficiencies of removal of ammonia levels were achieved in the range of 71.26%-90.91% (R1) and 62.32%- 92.21% (R2). The pH measurements at 20 days of HRT were in the range of 8.25-8.65 at R1 and pH 8.34-8.73 at R2. At 15 days of HRT, the effluent ammonia level removal efficiency at R1 decreased from 90.89% to 86.81% and at R2 decreased from 90.59% to 40.99%. At 15 days of HRT, the efficiency of ammonia level removal at R1 was better than that in R2 due to the addition of aeration to R1 at the end of the study. Keywords: ammonia, liquid waste, fertilizer industry, sequencing batch reactor

Pengaruh Suhu Proses Sokletasi dan Volume Pelarut n-heksana terhadap Yield Minyak Atsiri Jeruk Lemon Fania Zulfa Salsabila; Rosyidah Khoirunnisa Mahdan; Ghusrina Prihandini; Robby Sudarman; Fitria Yulistiani
Fluida Vol 15 No 2 (2022): FLUIDA
Publisher : Jurusan Teknik Kimia, Politeknik Negeri Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35313/fluida.v15i2.4409

Essential oils are volatile compounds found in lemon peels. Essential oils are used in addition to soaps, perfumes, and candles because of their fresh aroma. Essential oils can be extracted using solid-liquid extraction. Soxhlet extraction was chosen because the process is continuous and requires less solvent than the percolation method. The solvent N-Hexane was chosen because its polar value was close to the polarity of the essential oil. Soxhlet extraction was carried out with variations in process temperature (70, 75, and 80°C) and solvent volume (16, 240, and 320ml). Previously, the lemon peel was pre-treated by drying (<100°C, 1 hour) and grinding. After extraction, the essential oil was added with anhydrous (Na2SO4). The best results were obtained at a process temperature of 80°C and a solvent volume of 320 ml yielding 3.25%. The increase in process temperature and solvent volume increases the yield of essential oils. Based on the results of the GC-MS analysis, lemon essential oil contains limonene (41.06%) and citral (12.2%). The content of limonene gives the aroma, and the content of citral gives color to the lemon essential oil. Abstrak Minyak atsiri merupakan senyawa volatile yang banyak ditemukan pada kulit jeruk lemon. Minyak atsiri digunakan sebagai tambahan sabun, parfum, dan lilin karena aromanya yang segar. Minyak atsiri dapat diambil menggunakan ekstraksi padat-cair. Ekstraksi sokletasi dipilih karena prosesnya kontinyu dan membutuhkan lebih sedikit pelarut dibandingkan metode perkolasi. Pelarut N-Heksana dipilih karena nilai polarnya mendekati kepolaran minyak atsiri. Ekstraksi sokletasi dilakukan dengan variasi suhu proses (70, 75, dan 80°C) dan volume pelarut (160, 240, dan 320ml). Sebelumnya dilakukan pre-treatment pada kulit jeruk lemon berupa pengeringan (<100°C, 1jam) dan penghalusan. Setelah diekstraksi, minyak atsiri diberi tambahan anhidrat (Na2SO4). Hasil terbaik diperoleh pada suhu proses 80°C dan volume pelarut 320 ml dengan hasil yield 3,25%. Peningkatan suhu proses dan volume pelarut meningkatkan yield minyak atsiri. Berdasarkan hasil analisis GC-MS minyak atsiri jeruk lemon mengandung limonene (41,06%), dan citral (12,2%). Kandungan limonene memberikan aroma dan kandungan citral memberikan warna pada minyak atsiri jeruk lemon.

Delaminasi Perekat Polivinil Asetat Berbasis Air Satu Komponen untuk Aplikasi Kayu Keras Ulin dan Merbau: Delamination on Polyvinyl Acetate Water Based Adhesive One Component for Ulin and Merbau Hard Wood Working Application Retno Indarti; Agustinus Ngatin; Robby Sudarman; Tifa Paramitha; Rony Pasonang Sihombing
KOVALEN: Jurnal Riset Kimia Vol. 8 No. 2 (2022): August Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2022.v8.i2.15900

Water-based adhesive was one of the most important media for bonding substrates to one another because of their environmental friendly character. Previously, in the application of hardwood adhesives such as Ulin and Merbau, the type of adhesive used was a two-component system. For this reason, a one-component water-based adhesive was introduced in this study. The advantage of these was environmental friendly and high durability. In this application, delamination was one of the important parameters to determine whether the adhesive used was well penetrated or not. For this reason, delamination will be the main parameter in this study. This research includes the preparation of tools and materials, manufacture of PVA (polyvinyl alcohol) solution, polymerization of polyvinyl acetate by mixing the main raw material of vinyl acetate monomer and PVOH solution using APS (ammonium persulfate) initiator. The polymerization process was carried out at 1 atm pressure and 75oC – 80oC temperature accompanied by stirring with ±500 rpm rotation rate. Final product is a homopolymer PVAc (polyvinyl acetate) with PVOH Z-210 with AAEM (acetoacetoxy ethyl methacrylate) content having an acetoxy functional group. A delamination test was carried out on the final product with a modified test based on Japanese Agricultural Standard 1152 where the product was immersed in water for 360 minutes, then placed in an oven at 40oC for 18 hours. Samples using PVOH with AAEM content have an average delamination rate of 0.67-1.67% while existing products on the market have an average delamination rate of 45.83-52.08%.

Effect of Microwave Pretreatment on Production of Reducing Sugar from Oil Palm Empty Fruit Bunches Budi Mandra Harahap; Robby Sudarman; Fildzah Sajidah; Diana Murti Indra Wahyuni; Dea Tesalonika Sitorus
Jurnal Teknik Kimia dan Lingkungan Vol. 4 No. 2 (2020): October 2020
Publisher : Politeknik Negeri Malang

ABSTRAK Perlakuan pendahulan biomassa merupakan tahapan terpenting dalam memproduksi produk-produk berbasis bio (bio-based products) secara biologis. Pada penelitian ini, energi gelombang mikro (microwave) digunakan selama perlakuan pendahuluan untuk meningkatkan kinerja proses sakarifikasi tandan kosong kelapa sawit (TKKS) menjadi gula-gula pereduksi. Faktor-faktor yang mempengaruhi perlakuan pendahuluan seperti daya (180-360 watt), waktu iradiasi (5-30 menit), dan solid loading (2,5%-7,5%) dievaluasi. Kinerja hidrolisis TKKS yang telah diberi perlakuan pendahuluan selanjutnya dianalisis dengan Cellic CTec2. Hasil penelitian menunjukkan bahwa cairan residu yang diperoleh setelah perlakuan pendahuluan menghasilkan gula pereduksi dalam jumlah yang rendah, yaitu antara 1,39 dan 3,92 mg/g-TKKS. Akan tetapi, setelah padatan residu dihidrolisis secara enzimatis, rendemen gula pereduksi meningkat secara signifikan. Menariknya, hanya pada level daya terendah (180 watt), gula pereduksi meningkat seiring dengan perpanjangan waktu iradiasi untuk semua solid loading. Sebaliknya, pada 360 watt, semakin lama waktu iradiasi diterapkan, semakin rendah gula pereduksi yang diperoleh untuk semua solid loading. Gula pereduksi tertinggi dihasilkan hingga 151 mg/g-TKKS, yaitu menggunakan 5% padatan pada 180 watt selama 25 menit. Berdasarkan hasil-hasil ini, perlakuan pendahuluan menggunakan gelombang mikro yang diikuti dengan hidrolisis enzimatis merupakan salah satu metode yang potensial untuk memproduksi gula dari TKKS. Pretreatment of biomass is the most crucial step in the biological production of bio-based products. In this study, microwave energy was used during the pretreatment process to enhance the saccharification performance of oil palm empty fruit bunches (OPEFB) into reducing sugar. The influential factors of pretreatment such as power level (180-360 watt), irradiation time (5-30 min), and solid loading (2.5%-7.5%) were evaluated. The performance of pretreated OPEFB hydrolysis was subsequently assessed by Cellic CTec2. The result showed that spent liquor produced after pretreatment only released a low amount of reducing sugar in the range between 1.39 and 3.92 mg/g-OPEFB. After residual solid was enzymatically hydrolyzed, a significant increase in the reducing sugar yield occurred. Interestingly, only at the lowest power level (180 watts), the reducing sugar rose along with the extension of irradiation time for all solid loadings. On the contrary, the longer irradiation time was applied, the lower reducing sugar was acquired at 360 watts for all solid loadings. The highest reducing sugar was produced up to 151 mg/g-OPEFB using 5% solid at 180 watts for 25 min. This indicated that microwave pretreatment followed by enzymatic hydrolysis was one of the potential methods to recover sugars in OPEFB.

Seeding and Acclimatization for Aerobic Processing of Restaurant Wastewater with Sequencing Batch Reactor Herawati Budiastuti; Laily Isna Ramadhani; Sudrajat Harris Abdulloh; Ananda Dea Maharani; Melina Melina; Robby Sudarman
Fluida Vol 16 No 1 (2023): FLUIDA
Publisher : Jurusan Teknik Kimia, Politeknik Negeri Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35313/fluida.v16i1.4521

Restaurant wastewater has a relatively high organic matter content, so it needs to be treated to meet the specified quality standard. One of the technologies that can be used in restaurant wastewater treatment is Sequencing Batch Reactor (SBR) technology. The purpose of this study is to set up an aerobic SBR system with seeding and acclimatization treatments to reduce the amount of organic matter in restaurant wastewater when a shock load occurs. The research was done using wastewater from a restaurant in Bandung and activated sludge from the food industry in Bogor as seeds for microorganisms. In this study, the seeding process was carried out by introducing 25% activated sludge and 75% nutrients into the reactor, and the acclimatization process was carried out by introducing a specific ratio of nutrients and wastewater into the reactor gradually until the waste concentration reached 100%. The parameters tested were COD, MLVSS, DO, pH, and temperature. During the seeding procedure, the initial COD value of 3,200 mg/L declined. It began to stabilize on the seventh day, with a COD value of 1,080 mg/L. The COD removal reached a relatively stable condition in the acclimatization process starting on day 2, where COD decreased from the original 1,280 mg/L to 480 mg/L.

Pengolahan Air Limbah Tahu Menggunakan Metode Elektrokoagulasi dan Adsorpsi Secara Kontinyu: Tofu Wastewater Treatment Using Continuous Electrocoagulation and Adsorption Method Ninik Lintang Edi Wahyuni; Nurcahyo; Unung Leoanggraini; Robby Sudarman; Bambang Soeswanto; Emma Hermawati Muhari; Agustinus Ngatin; Rony Pasonang Sihombing
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 2 (2023): August Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i2.16446

Tofu wastewater contains a lot of protein therefore it is easily degraded to produce foul odors and harmful gases due to microbes. Protein levels can be reduced through the electrocoagulation method which is equipped with adsorption. The purpose of this study is to reduce the value of turbidity, TSS, and COD in tofu wastewater due to the influence of voltage in the electrocoagulation process which is equipped with an adsorption process. This research was conducted with an electrocoagulation process at a rate of 250L/min with voltage variations of 15, 20, and 24Volt in a 10L tank containing 3 pairs of aluminum (Al) electrodes connected with direct current. The output water from the electrocoagulation process flows into the settling basin and flows into the adsorption tank containing activated carbon adsorbent. Both of these continuous processes were the innovation of this research. Sampling was conducted every 10 minutes for analysis of turbidity, TSS, COD, and pH. The results of the output water analysis from the electrocoagulation process after passing through the precipitation and adsorption processes show that increasing the voltage results in the decrease of turbidity, TSS, and COD values, however, increased efficiency and pH. Thus, a voltage of 24V with a flow rate of 250mL/min resulted in the highest efficiency of the voltage variations (15, 20, and 24V) with a process time of 90 minutes with a turbidity impurity reduction efficiency value of 45.42% with a value of 41.36 NTU from 75.22NTU, TSS 91.42% with a decrease to 1827mg/L from 21288mg/L, and COD 55.56% with a COD value of 9600mg/L from 21600mg/L, and a process output water pH of 4.91, as well as a reduction in aluminum electrode weight of 1.024grams.

The Study of Plasmonic Chip of Nata de Sago-green Silver Nanoparticles for Detection of Blood Glucose Abdul Haris Haris Watoni; La Ode A. Nur Ramadhan; Evy Nuryah Adha; Robby Sudarman
Chimica et Natura Acta Vol 11, No 2 (2023)
Publisher : Departemen Kimia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/cna.v11.n2.45909

The innovation of rapid blood glucose level detectors using chemical sensors still needs to be carried out continuously. Nata de sago has good potential as a safe sensor chip for blood glucose detection. To increase the detection speed, this sensor chip can be composited with silver nanoparticles (AgNPs)-bidara leaf extract which has plasmonic properties when interacting with visible radiation. The principle of blood glucose detection with the nata de sago-AgNPs-bidara leaf extract composite chip is based on van der Waals interactions between the functional groups in nata de sago and the hydroxyl groups in glucose compounds which are strengthened by the plasmonic nature of AgNPs.This study aims to synthesize and characterize nata de sago cellulose composite films embedded with silver nanoparticles as blood sugar detection sensor chips. Silver nanoparticles (AgNPs) were synthesized from AgNO3 precursors using bioreductors and capping agents of bidara leaf extract (Ziziphus mauritiana L.) with various volume ratios of precursor to bioreductor 1:1, 1:2, 1:3, 1:4, 1:5 and 1:6. The nata de sago-AgNPs-bidara leaf extract composite was made by soaking the nata de sago film in a suspension of AgNPs-bidara leaf extract for 1 hour until the film turned yellow. The film was then dried for 24 hours at room temperature to obtain a cuvette type plasmonic film which was ready for characterization and validation.FTIR analysis showed the formation of silver particles based on vibrational spectra changes of functional groups of bioreductor compounds at wave numbers 3423 cm-1, 2924 cm-1, 1641 cm-1 and 1056 cm-1. Morphological analysis using a digital microscope showed that the AgNPs were not uniformly spherical. Particle size analysis using a UV-Vis spectrophotometer showed that the AgNPs formed had an estimated diameter of 32.231 – 82.261 nm. Composite film of nata de sago-AgNPs-bidara leaf extract can be used as a blood glucose sensor chip by UV-Vis spectrophotometry with LOD = 30.814 mg/dL, LOQ = 50.814, %RSD = 5.015, and %R 90.68. The values of these parameters indicate that the sensor chip has good precision (%RSD) and accuracy (%R).

Co-Authors Abdul Haris Watoni Ajie Nurhasyim Alisya Nurbaits Ananda Dea Maharani Bambang Soeswanto Budi Mandra Harahap Budi Mandra Harahap Dea Tesalonika Sitorus Dea Tesalonika Sitorus Diana Murti Indra Wahyuni Diana Murti Indra Wahyuni Efniarsi S. Panggalo Emma Hermawati Muhari Evy Nuryah Adha Fania Zulfa Salsabila Fildzah Sajidah Fildzah Sajidah Herawati Budiastuti Jayanti, Retno Dwi La Ode A. Nur Ramadhan Melina Melina Nancy Siti Djenar Ngatin, Agustinus Ninik Lintang Edi Wahyuni Nurcahyo Paramitha, Tifa Prihandini, Ghusrina Ramadhani, Laily Isna Retno Indarti Rosyidah Khoirunnisa Mahdan Sihombing, Rony Pasonang Sudrajat Harris Abdulloh Suryadi, Joko Unung Leoanggraini Yulistiani, Fitria Yunus Tonapa Sarungu

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