Zwain, Haider Mohammed Naima (2016) Treatment Of Recycled Paper Mill Effluent Using Modified Anaerobic Inclining-Baffled Reactor. PhD thesis, Universiti Sains Malaysia.
|
PDF
Download (421kB) | Preview |
Abstract
Bahan berasaskan kalsium oksida (CaO) telah dicadangkan sebagai calon yang berpotensi untuk menyerap CO2 untuk mengurangkan pembebasan karbon dioksida (CO2) ke atmosfera terutamanya daripada loji kuasa pembakaran bagi bahan api fosil. Dalam penyelidikan ini, aragonit (CaCO3), kalsit (CaCO3), kalsium hidroksida (Ca(OH)2) dan bahan-bahan lengai digabungkan dengan kalsium hidroksida (Ca(OH)2) telah disintesis melalui proses hidroterma, hidroterma bersama sol-gel dan kaedah pemendakan. Pelbagai parameter: seperti suhu hidroterma (8 jam - 72 jam), penambahan poliakrilamida (PAM), kepekatan natrium hidroksida (NaOH) (2 M - 10 M), kepekatan cetrimetilamonium bromida (CTAB) (0.2 M - 0.9 M) dan penggabungan pelbagai bahan lengai (Mg, Zr, Ce dan (Zr-Ce)) telah dikaji. Kemudian, prestasi penjerapan CO2 oleh penjerap berasaskan kalsium oksida (CaO) dari sampel-sampel yang disintesis telah dikaji. Dalam kes kaedah hidroterma, rod nano aragonit (CaCO3) 1D telah diperhatikan pada sampel yang disediakan dengan menggunakan kaedah hidroterma selama 72 jam apabila PAM digunakan sebagai bahan tambah. Manakala rod nano aragonit 1D diperolehi tanpa penggunaan PAM pada sampel 12 jam. Kaedah sol-gel hidroterma bersama 2 M NaOH menghasilkan kalsit (CaCO3) 3D sferamikro berongga, manakala kalsium hidroksida (Ca(OH)2) berstruktur nano diperolehi melalui kaedah pemendakan pada 0.9 M CTAB. Mg, Zr, Ce dan (Zr-Ce) yang ditambahkan kepada Ca(OH)2 sampel mempamerkan morfologi permukaan yang berbeza. Kapasiti penjerapan CO2 kalsium oksida (CaO) yang diperolehi daripada rod nano aragonit CaCO3 1D, kalsit CaCO3 3D berstruktur nano sferamikro berongga dan kalsium hidroksida Ca(OH)2 selepas kitaran pertama adalah 0.80 g-CO2/g-penjerap, 0.62 g-CO2/g - penjerap dan 0.71 g-CO2/g-penjerap. Walau bagaimanapun, kapasiti ini menurun masing-masing kepada 0.38 g-CO2/g-penjerap, 0.39 g-CO2/g-penjerap dan 0.48 g-CO2/g-penjerap selepas 10 kitaran. Keputusan menunjukkan CaO yang terhasil daripada Ca(OH)2 dengan luas permukaan 64.57 m2/g mempamerkan kapasiti penjerapan CO2 terbaik selepas 10 kitaran (0.48 g-CO2/g-penjerap), tetapi penurunan kapasiti penjerapan dengan bilangan kitaran masih diperhatikan. Pembangunan kestabilan kitaran dapat diperhatikan dalam bahan penjerap berasaskan CaO yang diperolehi daripada sampel Mg, Zr, Ce dan (Zr-Ce) yang ditambahkan kepada Ca(OH)2. Bahan penjerap berasaskan CaO yang dihasilkan daripada Mg-Ca(OH)2 menunjukkan sedikit penurunan dalam kapasiti dari 0.67 g-CO2/g-penjerap kitaran pertama kepada 0.57 g-CO2 /g-penjerap selepas 10 kitaran, manakala bahan penjerap yang berasaskan CaO dihasilkan daripada Zr dan sampel Ce-ditambahkan kepada Ca(OH)2 masing-masing mempamerkan kestabilan kitaran yang jelas sepanjang 10 kitaran sebanyak, 0.38 g-CO2/g-penjerap dan 0.24 g-CO2/g-penjerap. Bahan penjerap berasaskan CaO yang diperolehi daripada asetat (Zr-Ce) yang digabungkan kepada Ca(OH)2 telah meningkatkan kapasiti daripada 0.59 g-CO2/g-penjerap selepas kitaran pertama kepada 0.63 g-CO2/g-penjerap selepas 10 kitaran. Kapasiti penjerapan yang lebih tinggi dan kestabilan kitaran yang lebih baik semasa 10 kitaran adalah disebabkan oleh luas permukaan BET yang tinggi (155.80 m2/g), pelbagai taburan saiz liang mikro/meso (1.7 nm - 30 nm) dan kehadiran Ce2Zr3O10 sebagai rintangan pensinteran pada suhu yang tinggi. ____________________________________________________________ Calcium oxide (CaO) based materials have been proposed as potential candidates for CO2 adsorption to reduce the emission of carbon dioxide (CO2) into the atmosphere especially from the combustion of fossil fuel power plants. In this research, aragonite (CaCO3), calcite (CaCO3), calcium hydroxide (Ca(OH)2) and inert materials incorporated calcium hydroxide (Ca(OH)2) were synthesized by hydrothermal, sol-gel assisted hydrothermal and precipitation methods, respectively. Various parameters such as hydrothermal temperature (8 h - 72 h), addition of polyacrylamide (PAM), sodium hydroxide (NaOH) concentration (2 M - 10 M), cetyltrimethyl ammonium bromide (CTAB) concentration (0.2 M - 0.9 M) and different inert incorporated materials (Mg, Zr, Ce and (Zr-Ce)) on as-synthesized samples were characterized. And then, the CO2 adsorption performances of calcium oxide (CaO) based adsorbents derived from as-synthesized samples were investigated. In the case of hydrothermal method, 1D aragonite (CaCO3) nanorods are observed at 72 h hydrothermal reaction time when PAM is used as an additive, whereas 1D aragonite nanorods are obtained without using PAM at 12 h reaction time. In sol-gel assistance hydrothermal method, 3D calcite (CaCO3) hollow microspheres are attained with 2 M of NaOH concentration, while nanostructured calcium hydroxide (Ca(OH)2) is obtained by precipitation method at high CTAB concentration of 0.9 M. On the other hand, Mg, Zr, Ce and (Zr-Ce) incorporated Ca(OH)2 samples exhibit different surface morphologies. The CO2 adsorption capacities of calcium oxide (CaO) derived from 1D aragonite CaCO3 nanorods, 3D calcite CaCO3 hollow microspheres and nanostructured calcium hydroxide Ca(OH)2 after first cycles are 0.80 g-CO2/g-adsorbent, 0.62 g-CO2/g-adsorbent and 0.71 g-CO2/g-adsorbent, respectively. However, these capacities drop to 0.38 g-CO2/g-adsorbent, 0.39 g-CO2/g-adsorbent and 0.48 g-CO2/g-adsorbent after 10 cycles, respectively. It can be seen that CaO derived from Ca(OH)2 with surface area 64.57 m2/g exhibits the best CO2 adsorption capacity after 10 cycles (0.48 g-CO2/g-adsorbent), but the decay in adsorption capacity with number of cycles is observed. The development of cyclic stability can be observed in CaO-based adsorbents derived from Mg, Zr, Ce and (Zr-Ce) incorporated Ca(OH)2 samples. The CaO-based adsorbent derived from Mg-Ca(OH)2 shows slightly decrease in capacity from 0.67 g-CO2/g-adsorbent after first cycle to 0.57 g-CO2/g-adsorbent after 10 cycles, while CaO-based adsorbents produced from Zr and Ce-incorporated Ca(OH)2 samples exhibit the obvious cyclic stability during 10 cycles, 0.38 g-CO2/g-adsorbent and 0.24 g-CO2/g-adsorbent, respectively. The CaO-based adsorbent derived from (Zr-Ce) acetates incorporated Ca(OH)2 sample increases the capacity from 0.59 g-CO2/g-adsorbent after first cycle to 0.63 g-CO2/g-adsorbent after 10 cycles. The higher adsorption capacity and better cyclic stability during 10 cycles are attributed to the high BET surface area (155.80 m2/g), a wide range of micro/mesopore size distribution (1.7 nm - 30 nm) and the presence of high temperature sintering resistance Ce2Zr3O10 compound.
| Item Type: | Thesis (PhD) |
|---|---|
| Subjects: | T Technology > T Technology (General) T Technology > TA Engineering (General). Civil engineering (General) > TA1-2040 Engineering (General). Civil engineering (General) |
| Divisions: | Kampus Kejuruteraan (Engineering Campus) > Pusat Pengajian Kejuruteraan Awam (School of Civil Engineering) > Thesis |
| Depositing User: | Mr Mohamed Yunus Mat Yusof |
| Date Deposited: | 27 Aug 2020 04:12 |
| Last Modified: | 17 Nov 2021 03:42 |
| URI: | http://eprints.usm.my/id/eprint/46994 |
Actions (login required)
 |
View Item |
