Plastic is one of the polymer materials that is widely used in daily lives, one of them is High-Density Poly Ethylene (HDPE) polymer which is the one type of the large contributors to plastic waste, and also believed to cause environmental and health problems. One of the advanced materials is lightweight brick which has become an innovation in building materials. Lightweight Hebel brick (celcon) is an infrastructure product that is widely used on this day. This study is entitled High-Density Poly Ethylene (HDPE) Polymers as Binders in Lightweight Hebel Bricks (Celcon). Referring to the research master plan of the Sriwijaya State Polytechnic namely appropriate technological and industrial innovation and technology development of mining products. In this study utilizing High-Density Poly Ethylene (HDPE) polymers as Binder and Portland Cement type I and silica Sand as Filler, in the process of making Lightweight Hebel Bricks (Celcon). The comparison of the Filler and Binder are 30:70, 40:60, 50:50, 60:40, 70:30 in %wt. Sample testing is done by testing the compressive strength, analyzing water absorption, density, and SEM & EDX. This research shows that the compressive strength produced is included in quality I and quality III according to SNI 03-0349-1989 which in the variation of filler sample A has a compressive strength of 224.67 kg/cm2 and variation of filler sample B is 40, 45 kg/cm2. The value of water absorption produced is also still below the maximum limit, which is 25% which in the variation of sample A filler is 0.97% and the variation of filler sample B is 2.42%. The density values obtained are included in the medium density for filler variation of sample A, which is 900 kg/m3 and high density for variation of filler sample B, which by 1800 kg/m3. SEM-EDX analysis results showed that sample A has more porosity when compared to variations of sample B filler. In terms of economic analysis, the advantage of using plastic as material in making Hebel bricks is the cost of making it economically due to the presence of plastic that is easily found.

The pandemic caused by COVID-19 virus is a big thing faced by people all over the world, including Indonesia. Washing hands with soap and water is one way to prevent the spread of COVID-19 virus. Soap formation is the saponification process which is the reaction between triglycerides and alkali that produces glycerol. One of the inovations on soap production is paper soap. Paper soap is a soap that easy to carry because its small and thin shape. Soap antiseptic properties can be produced by the addition of other materials, such as green betel leaves (Piper betle L) extract. This research aims are to produce paper soap product that compatible with SNI 3532:2016 characteristics and to get the best paper soap formulation. Paper soap production using coconut oil and Virgin Coconut Oil (VCO) and green betel leaves extract composition 2 ml. 4 ml and 6 ml. The analysis that has been done to determine soap characteristic is water content, insoluble in etanol, free fatty acid, free alkali pH, and foam stability. Characteristics of paper soap from coconut oil and VCO with 4 different treatments all according to the requirements of SNI 3532:2016 with a water content value of 0.25%-2.09%, insoluble ingredients in ethanol 0.112% -1.876%, free fatty acids 1.128% -2.425%, pH 9.25 -10.73, and foam stability 77.96% -90%.

Abu cangkang dan serabut kelapa sawit memiliki kadar silika tinggi yang dapat digunakan sebagai bahan baku sintesis silika gel. Silika gel mempunyai situs aktif berupa gugus silanol (Si-OH) dan siloksan (Si-O-Si) di permukaan. Dengan adanya gugus –OH memberikan peluang untuk memodifikasi gugus tersebut menjadi gugus lain yang lebih aktif. Tujuan dari penelitian ini yaitu untuk menghasilkan silika gel dengan nilai daya serap uap air yang lebih tinggi dan berfungsi lebih optimum sebagai adsorben. Penelitian dilakukan dengan tiga tahapan yaitu persiapan bahan baku, sintesis silika gel dan modifikasi, dan analisis  silika gel. Sintesis silika gel dilakukan dengan variasi konsentrasi H2SO4 1 - 5 M, waktu pematangan gel 12 dan 18 jam, dan massa difenilkarbazon 0,12 dan 0,18 g. Dari hasil penelitian didapatkan kondisi optimal sintesis silika gel terimobilisasi difenilkarbazon dicapai pada konsentrasi H2SO4 1 M, waktu pematangan gel 18 jam, dan massa difenilkarbazon 0,12 g. Pada kondisi ini diperoleh keasaman permukaan 6,15 mmol/g, luas permukaan 16,6150 m2/g, kadar air 8,4%, dan daya serap 10,960 mg/g.

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Energi listrik merupakan salah satu energi primer yang tidak dapat dilepaskan penggunaannya dalam kehidupan sehari-hari. Namun, sumber energi pembangkit listrik di Indonesia sebagian besar bergantung pada sumber daya alam yang tidak dapat diperbarui sehingga diperlukan suatu inovasi mengenai sumber energi pembangkit listrik alternatif. Salah satu contoh dari sumber energi listrik adalah kristal. Piezoelektrik adalah suatu kemampuan yang dimiliki sebagian kristal maupun bahan-bahan tertentu lainnya yang dapat menghasilkan tegangan listrik jika mendapatkan perlakuan tekanan, regangan dan vibrasi. Bahan utama pembuat kristal piezoelektrik sendiri adalah natrium karbonat dan kalium bitartrat yang salah satunya terkandung pada buah asam jawa (Tamarindus  Indica L.) sebesar 5,27% kalium bitartart yang digunakan sebagai bahan baku tambahan. Penelitian ini bertujuan untuk mengetahui pengaruh penambahan ekstrak asam jawa terhadap kualitas dan kuantitas Piezoelektric Crystal. Hasil penelitian menunjukkan bahwa produk Piezoelectric Crystal (PC) terbukti dapat dihasilkan melalui reaksi antara reaktan natrium karbonat dan kalium bitartarat untuk perbandingan %w/w dengan rasio (0,8:1) sebanyak (47,5:60 gram) dan variasi penambahan ekstrak asam jawa 5, 10, 15, 20 dan 25 mL berkonsentrasi 1,0189 M kalium bitartarat dalam ekstrak asam jawa mempengaruhi bertambahnya nilai %yield, voltase dan densitas produk dengan kondisi optimum penambahan ekstrak asam jawa yaitu pada 25 mL menghasilkan %yield, densitas dan voltase produk tertinggi sebesar 99,91%, 1,6608 gr/cm3 & 163 mV tanpa perlakuan variasi tekanan. Kata kunci : Piezoelectric Crystal, Asam Jawa (Tamarindus Indica L.), Energi Listrik.