Proceeding hasil karya Civitas Akademika Institut Teknologi Indonesia yang diterbitkan oleh lembaga lain. http://repository.iti.ac.id/jspui/handle/123456789/348 2026-03-10T04:46:09Z 2026-03-10T04:46:09Z Ratnawati, Ratnawati Enjarlis, Enjarlis Slamet, Slamet http://repository.iti.ac.id/jspui/handle/123456789/1446 2023-02-13T08:49:31Z 2017-01-01T00:00:00Z

Title: Combination of Ozonation and Photocatalysis for Pharmaceutical Wastewater Treatment Authors: Ratnawati, Ratnawati; Enjarlis, Enjarlis; Slamet, Slamet Abstract: The chemical oxygen demand (COD) and phenol removal from pharmaceutical wastewater were investigated using configuration of two circulation batch reactors in a series with ozonation and photocatalytic processes. The ozonation is conducted with O3/granulated activated carbon (O3/GAC), whereas photocatalysis with TiO2 that immobilized on pumice stone (PS-TiO2). The effect of circulation flow rate (10; 12; 15 L/min) and the amount PS-TiO2 (200 g, 250 g, 300 g) were examined. Wastewater of 20 L was circulated pass through the pipe that injected with O3 by the ozone generator, and subsequently flow through two GAC columns, and finally, go through photoreactor that contains photocatalyst PS-TiO2 which equipped with mercury lamp as a photon source. At a time interval, COD and phenol concentration were measured to assess the performance of the process. FESEM imaging confirmed that TiO2 was successfully impregnated on PS, as corroborated by EDX spectra. Meanwhile, degradation process indicated that the combined ozonation and photocatalytic processes (O3/GAC-TiO2) is more efficient compared to the ozonation and photocatalysis alone. For combination process with the circulation flow rate of 10 L/min and 300 g of PS-TiO2,the influent COD of around 1000 ppm are effectively degraded to a final effluent COD of 290 ppm (71% removal) and initial phenol concentration of 4.75 ppm down to 0 ppm for 4 h which this condition fulfill the discharge standards quality. Therefore, this portable prototype reactor is effective that can be used in the pharmaceutical wastewater treatment. For the future, this process condition will be developed for orientation on the industrial applications (portable equipment) since pharmaceutical industries produce wastewater relatively in the small amount

2017-01-01T00:00:00Z Ratnawati, Ratnawati Gunlazuardi, Jarnuzi Slamet, Slamet http://repository.iti.ac.id/jspui/handle/123456789/1445 2023-02-13T08:46:37Z 2017-01-01T00:00:00Z

Title: Photocatalytic Decomposition of Glycerol Solution on TiO2 Nanotube Arrays (TNTA) doped with C and N to Produce Hydrogen Authors: Ratnawati, Ratnawati; Gunlazuardi, Jarnuzi; Slamet, Slamet Abstract: Carbon and Nitrogen-doped TNTA were synthesized by in-situ anodic oxidation of Ti using glycerol containing NH4F followed by annealing with 20% H2/Argon at 500 oC. Variation water content in the electrolyte solution (25 and 37.5 v%) and time of anodic oxidation (1, 2, 4 and 6 h) that influence the morphology of TNTA and H2 produced was examined. At water content 37.5 v% in the electrolyte solution, FESEM results indicated that the disorder with not vertically oriented of the tube were observed. For water content 25 v%, TNTA with average inner diameters of 81 to 105 nm, wall thicknesses from 15 to 27 nm and lengths from 882 to 1705 nm were synthesized for 1-6 h anodization. Morphology of TNTA such as well developed, vertically oriented, ordered and long could influence photon absorption and, therefore, influence the accumulative H2 production. The result indicated that the average inner diameter of the tubes increase as anodic oxidation time increased up to 6 h, on the other hand, the tube length reached the maximum at 4 h anodic oxidation. TNTA that anodized for 2 h, water content in the electrolyte solution 25 v% with average tube length 1570 nm showed the highest accumulative H2 production (47 mmol/m2 photocatalyst).

2017-01-01T00:00:00Z Enjarlis, Enjarlis Ratnawati, Ratnawati Slamet, Slamet http://repository.iti.ac.id/jspui/handle/123456789/1444 2023-02-13T08:43:24Z 2015-01-01T00:00:00Z

Title: Pengaruh Proses Ozonasi, Adsorpsi don Advance Oxidation Process (O3/GAC dqn O3/H2O2) Pada Pengolahan Limbah lndustri Farmasi Authors: Enjarlis, Enjarlis; Ratnawati, Ratnawati; Slamet, Slamet

2015-01-01T00:00:00Z Ratnawati, Ratnawati Desela, Tania Slamet, Slamet http://repository.iti.ac.id/jspui/handle/123456789/1443 2023-02-13T08:37:13Z 2012-01-01T00:00:00Z

Title: Sintesis C-TiO2 Nanotube Array untuk Produksi Hidrogen dari Larutan Gliserol Authors: Ratnawati, Ratnawati; Desela, Tania; Slamet, Slamet Abstract: Kebutuhan hidrogen (H2) sebagai energi alternatif dari sumber terbarukan semakin meningkat, sementara teknologi dan kondisi optimum proses produksinya masih banyak diteliti untuk meningkatkan efisiensinya. Sintesis TiO2 nanotube array (TNTAs) dengan penambahan dopan karbon (C-TiO2) dan pengaruhnya dalam produksi hidrogen dari larutan gliserol telah dipelajari. TNTAs disintesis melalui proses anodisasi logam titanium dalam larutan elektrolit gliserol yang mengandung NH4F, dengan kadar air divariasi dari 5 % hingga 50 %. C-TiO2 diperoleh dengan mengkalsinasi TiO2 hasil sintesis pada suhu 500 o C dengan campuran gas H2 dan argon sebagai reduktor. Analisis SEM menunjukkan bahwa diameter nanotube TiO2 yang optimum diperoleh pada proses anodisasi dengan kadar air 25% dalam gliserol. Analisis UV-Vis DRS menunjukkan bahwa C-TiO2 nanotube array memiliki absorbansi yang lebih besar pada kisaran panjang gelombang cahaya tampak dari pada TiO2 nanopartikel dengan energi band gap turun menjadi 2,6 eV. Melalui proses fotoelektrokatalisis, hidrogen bisa diproduksi hingga 71,37 μmole.cm-2 katalis setelah 4 jam pengujian.

2012-01-01T00:00:00Z