EKUILIBRIUM Journal of Chemical Engineering
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Diabetes mellitus is a top five deadly disease in Indonesia. A healthy diet with consuming low sugar index food is suggested to prevent diabetes mellitus. Rice as the main source of carbohydrate in Indonesia is categorized as food with a high glycemic index. This study is experimenting rice with a low glycemic index that suitable to be consumed by diabetes mellitus sufferer. Various extracts are used in the making of low glycemic index rice such as strobilanthes crispus, cinnamon, and muntingia calabura. The rice is marinated with 1% extract for 2 hours and continued to cook in an autoclave for 15 minutes with temperature 116°C. The rice then dried in an oven at 50°C for 24 hours before it cooked in a rice cooker and can be consumed. The result shows that strobilanthes crispus and cinnamon extract rice has lower glycemic index than common rice.

<p>The textile industry in Indonesia is growing rapidly, this is confirmed by data from the Badan Pusat Statistik (BPS) which shows that the production of the clothing industry has experienced a significant growth of 15.29 percent in 2019. The use of textile dyes will cause waste problems in the environment. So we need natural dyes as a safer and environmentally friendly alternative. The purpose of this study was to obtain data analysis and to determine the adsorption equilibrium value of the natural dye solution of mangrove <em>Rhizophora stylosa</em> and tingi bark with variations in the amount of dyeing in primisima cloth by comparing it with the Langmuir and Freundlich equations and knowing the role of tunjung and alum in the process of fixing dyes into cloth. This study used a solid-liquid extraction method and then tested by spectrophotometry to obtain initial concentration data. Next, pour the dye that has been tested for its tannin content into a measuring cup and insert the cloth as a medium for mass transfer of tannins from liquid to solid. Samples were taken for each dyeing and tested for tannin content by spectrophotometry and the Ca value was obtained. Isotherm pattern testing. The adsorption test for the absorption process of tannins in natural dyes by cloth was carried out by calculating using the Langmuir and Freundlich equation. Furthermore, the cloth that has been dyed is fixed by tunjung and alum.The most suitable determination of the adsorption capacity of the cloth against natural dyes <em>Rhizopora stylosa</em> and tingi bark is by using the Freundlich adsorption equation compared to the Langmuir equation. This is evidenced by the error value of the Freundlich equation is smaller than the Langmuir equation by showing the value of R² which is close to number 1. The constant value of the Langmuir equation tingi bark for three times of dyeing obtained the b value is 0.2338 mg/gr and the k value is 0.00517 L/gr. For five of dyeing, the b value is 0.10817 mg/gr and the k value is 0.00421 L/gr. For the seven times of dyeing, the b value is 0.0670 mg/gr and the k value is 0.003899 L/gr. Whereas in the Freundlich equation for tingi bark for three times of dyeing, the n value is 0.4312 mg/g and the k value is 0.36374 x 10³ L/gr. For five of dyeing, the n value is 0.30114 mg/g and the k value is 0.99586 x 10⁵ L/g. For seven of dyeing, the n value is 0.2424 mg/g and the k value is 0.9354 x 10⁷ L/g. The constant value of the Langmuir <em>Rhizopora stylosa</em> equation for three times of dyeing, the b value is 0.15635 mg / gr and the k value is 0.005224 L/gr. For five of dyeing, the b value is 0.08141 mg/gr and the k value is 0.004415 L/gr. For the seven of dyeing, the b value is 0.04909 mg/gr and the k value is 0.00408 L/gr. Whereas in the Freundlich equation for  <em>Rhizopora stylosa</em> for three times of dyeing, the n value is 0.3862 mg/g and the k value is 0.1090 x 10⁴ L/g. For five of dyeing, the n value is 0.2733 mg/g and the k value is 0.4355 x 10⁶ L/g. For seven of dyeing, the n value is 0.2126 mg/g and the k value is 0.1545 x 10⁹ L/g. It can be concluded that the more dyeing, the less the absorbency of the cloth on tannins. The color change of fixation the cloth in the dyeing of <em>Rhizopora stylosa</em> extract with tunjung is from brown to grayish brown, while with alum from brown to dark brown. The color change of fixation the cloth in the dyeing of tingi bark extract with alum is from brown to black, while with alum from brown to dark brown.</p>@font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536869121 1107305727 33554432 0 415 0;}@font-face {font-family:Garamond; panose-1:2 2 4 4 3 3 1 1 8 3; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:647 2 0 0 159 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin-top:0cm; margin-right:0cm; margin-bottom:0cm; margin-left:.5pt; text-align:justify; text-justify:inter-ideograph; text-indent:-.5pt; line-height:103%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Garamond",serif; mso-fareast-font-family:Garamond; mso-bidi-font-family:Garamond; color:black; mso-ansi-language:EN-US; mso-fareast-language:EN-US;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:11.0pt; mso-ansi-font-size:11.0pt; mso-bidi-font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:DengXian; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-ansi-language:EN-US; mso-fareast-language:EN-US;}.MsoPapDefault {mso-style-type:export-only; margin-bottom:8.0pt; line-height:107%;}div.WordSection1 {page:WordSection1;}

<p>The heavy metal content is very dangerous because it can pollute the environment. One of the heavy metals waste commonly found in the textile industry is chromium (Cr). <em>Mimosa pudica</em> is a weed plant and its availability is very abundant. However, it also contains tannin which can be developed into tannin gel biosorbent to adsorption heavy metal content in the wastewater. The purpose of this research is to study <em>Mimosa pudica</em> tannin as a Cr biosorbent from textile wastewater. There are two steps to synthesis tannin gel biosorbent. They are the tannin extraction and the condensation polymerization process. Tannin is easily soluble in water so the condensation polymerization process is needed to make it insoluble in water. The extraction of <em>Mimosa pudica </em>tannin was done using water solvent. The condensation polymerization process was done by the reaction of tannin extract and formaldehyde. The Cr content of textile industry wastewater in the Pasar Kliwon, Surakarta was 4 ppm. The results of the biosorption of Cr heavy metal using <em>Mimosa pudica</em> tannin gel showed that the remaining Cr heavy metal was 0.7098 ppm. It was already below the threshold which was 1 ppm.</p><p> </p><p><strong>Keywords:</strong> biosorption, condensation polymerization, extraction, <em>Mimosa pudica</em>, tannin gel</p>

<p><em>Conductive Polymer Nanocomposites</em> (CPC) merupakan material yang banyak digunakan sebagai sensor, sel fotovoltaik, kapasitor, dioda, dan perangkat energi yang sangat mudah meregang. CPC memiliki beberapa sifat unggul, diantaranya konduktivitas elektrik yang tinggi, ringan, tahan korosi, dan memiliki karakteristik mekanis yang bagus. Konduktivitas elektrik pada polimer diperoleh dan diatur dengan menambahkan bahan isian berbasis karbon seperti: <em>Carbon Black</em> (CB), <em>Carbon Nano Tube</em> (CNT), <em>Graphite</em> maupun <em>Graphene</em>. Metode panambahan bahan isian dapat dilakukan dengan<em> </em><em>Melt </em><em>b</em><em>lending</em><em> </em>dan <em>Solvent blending.</em> Metode <em>melt</em> <em>blending</em><em> </em>memiliki beberapa keunggulan, diantaranya mudah, praktis, murah, serta dapat diaplikasikan pada berbagai bahan. Selain itu, metode <em>melt blending</em> termasuk  ramah lingkungan karena tidak ada pelarut organik. Sedangkan kelebihan metode <em>Solvent Blending </em>adalah campuran yang lebih kuat dikarenakan <em>disperse</em> yang terjadi merata dan lebih baik. Pada<em> revie</em><em>w,</em> penulis mengulas tentang sifat elektrik dari CPC berbasis poli asam laktat dan berbagai bahan isian  karbon, yaitu CNT, <em>graphene</em>, dan CB. Hasil studi literatur menunjukkan bahwa konduktivitas elektrik CPC meningkat seiring bertambahnya komposisi bahan isian<em>.</em> Pada metode <em>solvent blending </em>faktor yang berpengaruh adalah komposisi PLA dan <em>filler</em>, suhu operasi, kecepatan pengadukan, waktu pengadukan, dan <em>solvent</em> yang digunakan. Sedangkan metode <em>melt blending</em> faktor yang berpengaruh adalah komposisi PLA dan <em>filler</em>, suhu operasi, kecepatan, dan waktu.</p><p> </p><p>Kata kunci: Poli Asam Laktat, CNT, CB, <em>Graphene</em>, CPC</p>

<p>Hydrothermal liquifaction is a biomass conversion process, where the structure of the biomass is convert into liquid components under super critical conditions with a high temperature. In this study, glucose is used as biomass. The purpose of this study was to study the reaction kinetics and determine the hydrothermal decomposition of glucose in NaOH solution. This experiment used 10 grams of glucose and dissolve it in 80 mL of NaOH solution then put it in an autoclave. Experiments were carried out by varying the heating temperature carried out in an autoclave with a magnetic stirrer. After heating at various temperatures, the autoclave is immediately cooled down. The processed material is filtered to separate insoluble solids from the liquid phase. The solid residue that has been separated from the liquid phase is then dried in an oven at 105°C for 24 hours. The composition of the filtrate was analyzed using the GC-MS method and the glucose concentration was analyzed using the Lane Eynon method. Prior to GC-MS analysis, the filtrate was distilled at atmospheric pressure until a solid residue remained. The sample analyzed is the result of distillation with a temperature above 100°C to ensure that there is no water and residual glucose in the sample. The results of GC-MS analysis of product samples from the hydrothermal decomposition process had 3 peaks. The first peak shows the compound 1,3 Dipalmitin which has an area of 14.74%, the second peak shows the Olealdehyde compound which has an area of 32.35%, and the third peak shows the 1,2-Epoxyhexadecane compound which has an area of 52.91%. The kinetics results in hydrothermal decomposition of glucose in this experiment obtained a reaction order of 2 with an activation energy (Ea) of 15.91 KJ / mol and a pre-exponential factor of 66.12.</p>

With the increasing development of the battery and electric vehicle industry, student's and teacher's understanding of lithium batteries and skills in assembling electric bikes are very important in competing for jobs in these fields. Educational activities regarding batteries and training on assembling electric bike are carried out at SMK Muhammadiyah 6 Karanganyar, because there were no facilities that support the learning and teaching process about electric vehicles and batteries. The method used in this training is lecture, discussion and practice method. The material presented was about the technology of making lithium batteries and electric bike components. While practical activities include the stages of converting conventional bikes into electric bikes with energy from lithium batteries. This activity shows that participants can understand batteries and can apply batteries to electric vehicles, especially electric bikes.

Chromium is one of the hazardous heavy metal contained in the industrial wastewater. It can be reduced by various methods, such as adsorption. The purpose of this study was initialized an activated carbon from coconut fiber by various phosphoric acid (H₃PO₄) activator concentration (0,1M; 0,5M; 1M; 1,5M; 2M) and variation of contact time (30; 60; 90; 120; 150; 180 minutes) to obtain optimum adsorption capacity of chromium. Analysis of the activated coconut fiber carbon by SAA obtained a surface area of 53,39 m²/g. The potassium chromate (K₂CrO₄) solution was adsorbed by the adsorbent and then analyzed by a UV-VIS Spectrophotometer to measure the chromium content. This study proved that chromium adsorption by activated coconut fiber carbon was increased by the time until reaching optimum condition. Enhancement of adsorption capacity was directly proportional as the more concentrated phosphoric acid activator. Maximum adsorption capacity obtained was 3,464 mg/g and the optimum condition was at contact time of 150 minutes with the phosphoric acid activator concentration of 2M.

<p>In general, natural dyes for textile materials are obtained from extracts part of the plants such as roots, wood, leaves, seeds, and flower. Textile industry especially batik craftsman, have known many plants that can dye textile materials, such as indigo (<em>indigofera</em><em>)</em>, soga tingi bark (<em>Ceriops tagal</em><em>)</em>, tegeran wood (<em>Cudraina javanensis</em><em>)</em>, turmeric (<em>Curcuma</em>), tea (<em>The</em>), noni root (<em>Morinda citrifelia</em>), soga jambal bark <em>(Pelthophorum ferruginum</em>), kesumba (<em>Bixa orelana</em>), and guava leaf (<em>Psidiumguajava</em>). Soga tingi bark chosen because it can produce tannins which can be used as natural dyes. The purpose of this research was to obtained tannin content in soga tingi bark as qualitatively and quantitatively. The analysis carried out is FTIR and HPLC method. FTIR analysis carried out to determine of the compounds contained in the soga tingi bark extraction. Based on FTIR analysis it can be seen that there are O-H and N-H group in the wavenumber 3375,13 cm^-1. C=O bond at wavenumber 1739,16 cm^-1. C=C bond at wavenumber 1624,31 cm^-1. C-H bond at wavenumbers 2970,72 cm^-1, 1456,39 cm^-1, and 1365,74 cm^-1. NO₂ bond at wavenumber 1365,74 cm^-1. C-N bond at wavenumbers 1228,69 cm^-1 and 1217,34 cm^-1. And C-O bond at wavenumbers 1228,69 cm^-1, 1217,34 cm^-1, and 1052,3 cm^-1. While HPLC analysis carried out to determine contains tannin level in the soga tingi bark extraction. HPLC conditions used are Flowrate: 1 mL/min, Mobile phase: MeOH : H₂O (50:50), λ: 271 nm and Column: C18, 250 mm. Based on HPLC analysis it is known that the contains tannin level in the soga tingi bark extraction is 22,44 ppm.</p>

<p>Kendaraan listrik merupakan kendaraan yang digerakkan dengan motor listrik dan mendapat sumber daya listrik yang tersimpan dalam baterai. Keuntungan penggunaan kendaraan listrik dibandingkan dengan kendaraan konvesional antara lain, efisiensi konversi energi yang tinggi, mengurangi pemakaian bahan bakar minyak sehingga secara langsung dan mengurangi emisi gas buang ke atmosfir. Riset grup matertial maju dan energy storage fokus mengembangkan penelitian tentang produksi baterai dan aplikasinya. Kegiatan pengabdian ini bertujuan untuk mensosialisasikan hasil riset tentang baterai dan aplikasi kendaraan listrik sebagai salah satu cara transfer pengetahuan teknologi untuk pelajar Sekolah Menengah Kejuruan (SMK). Siswa SMK harus dibekali dengan pemahaman mengenai baterai lithium ion dan kendaraan listrik sehingga bisa meningkatkan kompetensi lulusan dan memiliki daya saing di pasar kerja. SMK Muhammadiyah 6 Karanganyar memiliki jurusan Teknik Audio Video, Teknik Komputer Jaringan, Teknik Mesin, Teknik Elektro dan Mekanik Otomotif sehingga kegiatan dan kerjasama ini akan sangat mendukung kegiatan pembelajarn. Kegiatan pengabdian ini merupakan tindak lanjut kerja sama magang siswa yang dilakukan di unit produksi baterai dibawah Pusat Unggulan Iptek (PUI) PT Teknologi Penyimpanan Energi Listrik (University Center of Excellence for Electrical Energy Storage Technology). Dengan terselenggaranya kegiatan pengabdian diharapkan mampu memberikan pengetahuan mengenai hasil riset kampus kepada siswa, sehingga dapat memberikan pemahaman mengenai konsep dasar kendaraan listrik dan menumbuhkan inovasi pada siswa untuk mengembangkan kendaraan listrik.</p><p> </p><p><strong>Keywords:</strong> Edukasi , Baterai Ion Lithium, Kendaraan Listrik,</p>

Rice is a carbohydrate source and staple food for around the world of people, specially in Asia. Carbohydrate consumption , especially rice, can have effects of diabetes desease type 2. It is caused by the glycemic index of white rice is higher of 56. This research was conducted to study the effects of parboiled ciherang rice and extract of keji beling leaf. The rice was submerged for 6 hours so the mouisture increased to 30%. It was cooked in an autoclave at 116 ^oC for 15 minutes. The cooked rice then it was dried at 50 oC for 24 hours. This method didn’t have effects on reducing glycemic index but it increased the glycemic index higher than 54, e.g. 56 by tester 1 and 80 by tester 2.