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Siregar, Sri Hilma
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Pulp synthesis using bamboo raw materials through unbleached and bleached processes Siregar, Sri Hilma; Rahmadini, Syafri; Hasmalina, Nasution; Rizki, Ramadhanti Aulia; Eri , Kafri
Acta Chimica Asiana Vol. 6 No. 1 (2023)
Publisher : The Indonesian Chemical Society, Chapter Nusa Tenggara and The University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/aca.v6i1.135

Abstract

This study aims to see the potential of bamboo as a new raw material for the Indonesian pulp industry, specifically for the manufacture of pulp products, because in Indonesia, the import value for dissolving is still high, and the raw materials used still use wood plants. This study consists of three stages: the pre-hydrolysis stage using water, the cooking stage with the kraft pulping method, and bleaching using the elemental chlorine-free (ECF) method. Bamboo flakes that run into the pre-hydrolysis process decreased the Kappa Number value of pulp produced, which ranges from 4.63% - 14.52% compared to bamboo flakes that do not run into the pre-hydrolysis process. The brightness increase to 0.844% - 2.96% compared to bamboo flakes that do not run into the process of pre-hydrolysis. For pulp products, the value of Alpha Cellulose obtained is around 89.18% - 90.32%.
Synthesis and characterization of TiO2-Fe for photocatalytic applications of domestic waste Rahmadhani, Annisa; Nasution, Hasmalina; Prasetya, Prasetya; Dayumita, Novialis; Siregar, Sri Hilma
Acta Chimica Asiana Vol. 6 No. 1 (2023)
Publisher : The Indonesian Chemical Society, Chapter Nusa Tenggara and The University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/aca.v6i1.140

Abstract

Wastewater originating from household, industrial, and public places that contains materials can endanger human life and living things and disrupt environmental sustainability. Various methods have recycled domestic wastewater. One is through the photodegradation process utilizing ultraviolet light in the photocatalytic process. Inorganic materials are semiconductors with photocatalyst activity that can absorb photons and simultaneously carry out material interface transformation reactions. The research aimed to determine the effect of adding Fe metal dopants on TiO2 photocatalyst activity in simulated methylene blue and domestic waste treatment. The precursor used was TiO2 P25 Degussa Anatase. Fe dopant was added using the hydrothermal method with variations of 2%, 4%, and 6%. The XRD characterization results show that TiO2 has a high degree of crystallinity, so the overall process of electron diffusion and electron transfer in SSPT is higher to increase its efficiency. SEM-EDX characterization results show that TiO2-Fe particles are scattered in a spherical shape with a size of less than (<)100 nm and tend to agglomerate. Test results of simulated methylene blue (MB) waste with a UV-Vis spectrophotometer at variations in mass, concentration, pH, and time showed that the addition of doping could increase photocatalytic activity and optimum conditions at 6% (F6) were used in the analysis of parameters pH, COD and TSS of domestic wastewater. The pH value increased from 5 to 6, % COD degradation was 59.17%, and TSS was 23.07%. This research showed that TiO2-Fe was effective enough for domestic wastewater treatment.
The Fatal error: [File:D:/build/++Portal/Sync/Engine/Source/Runtime/Core/Private/Internationalization/ICUInternationalization.cpp] [Line: 153] ICU data directory was not discovered: ../../../Engine/Programs/CrashReportClient/Content/Internationalization ../. Siregar, Sri Hilma; Syahbella, Olif; Ramadhanti, Aulia Rizki
Acta Chimica Asiana Vol. 7 No. 1 (2024)
Publisher : The Indonesian Chemical Society, Chapter Nusa Tenggara and The University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/aca.v7i1.176

Abstract

This research aims to determine the quality of bricks mixed with different variations of sawdust and three types of testing and two characterizations have been carried out. The process of making bricks with the addition of wood dust is carried out by mixing montmorillonite and wood powder until homogeneous, with a mixture percentage of wood powder and bentonite of 0% (as a control), 10%, 20%, 30% and 50%, then dried and burned. Then the bricks are tested for three parameters, namely compressive strength test, acoustic test and water absorption test. Based on the test results, each test parameter obtained was a minimum compressive strength value of 43.75 kg/cm2 and a maximum of 82.57 kg/cm2, where variations 1 and 2 met the quality requirements (according to class III category according to SNI 15-2094- 2000). The acoustic test results obtained the best results in all variations in the second and third tests at Ls (night level) and the water absorption value was obtained at a minimum of 11.16% and a maximum of 60.98%, where variation 1 meets the quality requirements (according to SNI 15 standards –2094–2000).