Claim Missing Document
Check
Articles

Found 28 Documents
Search

Adsorption of congo red using kaolinite-cellulose adsorbent Santa Oktavia Ginting; Risfidian Mohadi
Science and Technology Indonesia Vol. 2 No. 2 (2017): April
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (747.113 KB) | DOI: 10.26554/sti.2017.2.2.29-36

Abstract

Kaolinite was impregnated with cellulose extracted from rubber wood fibers has been done. The product of impregnated kaolinite-cellulose was characterized using FT-IR spectrophotometer. Furthermore, the impregnation results are used as an adsorbent of Congo red. Adsorption of Congo red was also studied the kinetic and thermodynamic parameters. The results of characterization using FT-IR spectrophotometer shows the process of impregnation was successfully conducted. It was indicated that the presence wavenumber at 910.4 - 918.12 cm-1 and 1033.85 cm-1 become 1026.13 cm-1 and the existence of vibration at wavenumber 2931.8 cm-1. The pH of adsorption was adjusted to 4 before the adsorption process. The adsorption process of cellulose impregnated kaolinite shows the rate of adsorption (k) of 0.002 min-1, the adsorption reviews largest capacity (b) at 50 °C was 500 mol/g. The greatest adsorption energy (E) at 40 °C is 11:09 kJ/mol. The enthalpy value (ΔH) and entropy (ΔS) decreased with increasing Congo red dye concentration. Keywords: kaolinite, cellulose, impregnation, Congo red
Preparation, characterization, and thermal stability of B2O3-ZrO2 Theresia Debora Simbolon; Risfidian Mohadi
Science and Technology Indonesia Vol. 2 No. 2 (2017): April
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (357.15 KB) | DOI: 10.26554/sti.2017.2.2.56-58

Abstract

Synthesis of the borate-based compound with ZrOCl2 to form B2O3-ZrO2 has been conducted. The compound was characterized by FT-IR spectrophotometer, X-ray diffraction, acidity and thermal stability test. The results showed that the FT-IR main vibration spectrum of B2O3-ZrO2 compound has appeared at wave number 401.2 cm-1 for Zr-O bonding vibration, 617.2 cm-1 for B-O-B bonding vibration and 910.4 cm-1 for B-O bonding vibration. The XRD diffraction pattern shows B2O3-ZrO2 compound has an amorphous structure. The FT-IR spectrum after saturated with ammonia and potentiometric titration indicates that the compound of B2O3-ZrO2 has acidic properties with a strong level of acidity. Thermal stability test shows that the B2O3-ZrO2 compounds have high stability on temperature with increasing crystallinity after the compound was heated at 700 °C. Keywords: B2O3-ZrO2, impregnation, thermal stability.
Calcium oxide from Pomacea canaliculata and Babylonia spirata snails Triayu Septiani; Nurlisa Hidayati; Risfidian Mohadi
Science and Technology Indonesia Vol. 2 No. 3 (2017): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (444.253 KB) | DOI: 10.26554/sti.2017.2.3.68-70

Abstract

The preparation of CaO from golden snail (Pomacea canaliculata) and lion snail (Babylonia spirata) through decomposition at various temperature i.e 700o, 800o, 900o and 1000oC during 3 hours has been carried out. Calcium oxide from decomposition was characterized using X-Ray diffractometer. Furthermore, the characterization was continued using FT-IR spectrophotometer and determination of surface area using BET analysis. The results showed that the optimum temperature for preparation of CaO from golden snail and lion snail at 900oC with 2q values are: 32.2° , 37.4o , 54o , 64.2o , 67.3° and 32.4°, 37.5°, 67.5 °, respectively. FT-IR spectra showed characteristic vibrations for the Ca-O in the sample golden snail and lion snail combustion products at a temperature of 900oC. Ca-O absorption of golden snail samples in the wavenumber around 362.62 cm-1 and lion snail seen in wavenumber around 384.76 cm-1 indicating the presence of Ca-O vibration of the metal oxide of preparation. Golden snail and the lion snail combustion at 900oC temperature of each sample which has a surface area of 20.495 m2/g, while the lion snail 17.308 m2/g. The pore diameter of golden snail 3.753 nm and 11.319 nm of lion snail. All CaO can be categorized as mesoporous material. Keywords: golden snail, lion snail, decomposition, CaO
Preparation of calcium oxide from cattle bones as catalyst for conversion of waste cooking oil to biodiesel Sabat Okta Ceria Sitompul; Risfidian Mohadi
Science and Technology Indonesia Vol. 2 No. 3 (2017): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (712.281 KB) | DOI: 10.26554/sti.2017.2.3.76-79

Abstract

Preparation of calcium oxide from cattle bones by thermal decomposition for 3 hours using various temperature at 400°, 500°, 800°, 900°, 1000°, and 1100°C. Calcium oxide was characterized using X-Ray Diffractometer. The results of XRD pattern showed of diffraction similar to CaO standard from JCPDS at 2θ: 32.2°; 37.3°; 53.8°; 64.1° and 67.3°. The CaO from heating cattle bones at 1000°C resulting of 2θ: 32.3°; 53.8° and 64.1°. Then, the metal oxide was characterized by FT-IR which showed the existence of CaO at wave number 362.2 cm-1 from CaO vibration. The CaO from cattle bones applied as catalyst on biodiesel synthesis from waste cooking oil and resulting viscosity value of biodiesel 5.93 cSt, density 0.876 g/cm3, acid value 0.561 mg/KOH and iod number value 16.92 g/100 g, respectively all in the range of SNI standard. Keywords: cattle bones, calcium oxide, catalyst, biodiesel, waste cooking oil.
Adsorption of procion red and congo red dyes using microalgae Spirulina sp Risfidian Mohadi; Zazili Hanafiah; Hermansyah Hermansyah; Hilda Zulkifli
Science and Technology Indonesia Vol. 2 No. 4 (2017): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (408.734 KB) | DOI: 10.26554/sti.2017.2.4.102-104

Abstract

Adsorption of procion red and congo red dyes using microalgae Spirulina sp was conducted. Spirulina sp was obtained by cultivation and production in laboratory scale. Spirulina sp was used as adsorbent for adsorption of dyes. Adsorption process was studied by kinetic and thermodynamic in order to know the adsorption phenomena. The results showed that kinetically congo red is reactive than procion red on Spirulina sp. On the other hand, thermodynamically procion red was stable than congo red on Spirulina sp which was indicated by adsorption capacity, enthalpy, and entropy.
Diversity of Cu and Total Cr Metals in Surface Water and Sludge of Textile Wastewater from Tuan Kentang Village Seberang Ulu I Sub District Palembang Mirza Firdyah Astari; Adipati Napoleon; Risfidian Mohadi
Science and Technology Indonesia Vol. 3 No. 1 (2018): January
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (560.796 KB) | DOI: 10.26554/sti.2018.3.1.45-48

Abstract

Nowadays, the production of rainbow fabric as a traditional fabric of Palembang city has been grown rapidly. Commonly, the wastewater as the by-product of rainbow fabric production is discharged directly to domestic channels without any previous wastewater treatment. This research was aimed to evaluate the presence of Cu and total Cr heavy metal in the area of rainbow fabric industrial center in Tuan Kentang Village, Sebrang Ulu I Sub Distric, Palembang. The Cu and total Cr polluted in the collected wastewater sample was analyzed by using atomic absorption spectrometry method with wet destruction technique. The results indicated that the area of Tuan Kentang villages is contributing metal contaminants distribution and accumulation to nature.
Influence of Temperature and Particle Size on Heating Value of Biobriquette from Rubber Seed Tiara Armita; Sri Haryati; Risfidian Mohadi; Puteri Kusuma Wardhani
Science and Technology Indonesia Vol. 4 No. 2 (2019): April
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (774.353 KB) | DOI: 10.26554/sti.2019.4.2.57-59

Abstract

Rubber seed as a biomass is potentially used as the source of alternative energy in briquette. Previous research had found that rubber seed briquette has the highest heating value of 6287,8 cal/g. It can be increased by varying temperature and mesh size. In this research, the effect of temperature and particle size on the amount of heat of rubber seed biobriquette from Muarakuang (Batu Raja) was investigated. It was done in Politeknik Negeri Sriwijaya Palembang laboratory. Proximate analysis was executed in Politeknik Negeri Sriwijaya Palembang coal laboratory. The temperature varied of 250 oC, 500 oC, and 750 oC with the particle size varied by 80 mesh, 120 mesh, and 200 mesh. Quality test of fabricated biobriquette consisted of proximate analysis such as calorific value, inherent moisture, ash ratio, volatile matter ratio, and fixed carbon ratio. The highest of heating value was 6836 cal/g from biobriquette sample were found under particle size of 80 mesh and temperature of 250 oC. The heating value reached 5371 cal/g which the particle size was 200 mesh and temperature of 750 oC. The heating value of biobriquette were compared with Indonesian National Standardization (SNI), which met with the standard of heating value (5000 cal/g).
Kinetic and Thermodynamic Adsorption of Cr(VI) onto Dried Oscillatoria Splendida in Aqueous Solution Risfidian Mohadi; Doni Setiawan; Hilda Zulkifli
Science and Technology Indonesia Vol. 3 No. 4 (2018): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (618.436 KB) | DOI: 10.26554/sti.2018.3.4.195-198

Abstract

Kinetic and thermodynamic adsorption study of Cr(VI) ion in aqueous solutions by dried Oscillatoria Splendida biomass was investigated in the batch system. The Oscillatoria Splendida was isolated and cultured from algae swamp ecosystem in South Sumatera. The adsorption properties of Cr(VI) onto dried Oscillatoria Splendida biomass was studied by the influences of contact time, initial Cr(VI) ion concentration and temperature of reaction. The experimental results were the rate of adsorption followed the second-order kinetic model with the rate of reaction k2 is 0.00181 mg g-1 min-1 and the adsorption thermodynamic agree to the Langmuir’s model with amount of Cr(VI) removed from aqueous solution increased with increasing Cr(VI) concentration with the higher adsorption energy was 8.46 kJ/mol at 50 °C.
Adsorption of Cobalt (II) on Layered Double Hydroxides (Mg/Al and Ca/Al) In Aqueous Medium : Kinetic and Thermodynamic Aspect Neza Rahayu Palapa; Tarmizi Taher; Muhammad Said; Risfidian Mohadi; Aldes Lesbani
Science and Technology Indonesia Vol. 3 No. 4 (2018): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (688.808 KB) | DOI: 10.26554/sti.2018.3.4.189-194

Abstract

Layered double hydroxides Mg/Al and Ca/Al has been synthesized by co-precipitation method with molar ratio M2+:M3+ (3:1) at pH 10. The synthesized materials were characterized by XRD and FTIR. The materials were used as adsorbent for the removal Cobalt (II) in aqueous solution. The adsorption experiments were studied through some variables adsorption such as variation of contact time, variation of temperature and variation of initial concentration. Kinetic parameters was obtained from variation of contact time. Data was analyzed by pseudo-first-order and pseudo-second-order kinetics models in linear analyses. The kinetic studies showed that the adsorption process more fitted by pseudo-second-order than pseudo-first-order based on coefficient correlation. Isotherm parameters was calculated using Langmuir and Freundlich isotherm models. The adsorption process was spontaneous and endothermic.
Modification Of Zn-Cr Layered Double Hydroxide With Keggin Ion [?-SiW12O40]4- AS Cr(VI) Adsorbent Melantina Melan Oktriyanti; Neza Rahayu Palapa; Risfidian Mohadi; Aldes Lesbani
Indonesian Journal of Environmental Management and Sustainability Vol. 3 No. 3 (2019): September
Publisher : Research Centre of Inorganic Materials and Complexs

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (984.079 KB) | DOI: 10.26554/ijems.2019.3.3.93-99

Abstract

Abstract: In this study, synthesis of layered double hydroxide of Zn-Cr and Zn-Cr intercalated with keggin ion [SiW12O40]4- have been carried out. The synthesized material was characterized using XRD, BET, and FTIR. Material of Zn-Cr layered double hydroxide and the intercalation results are used as Cr(VI) ion adsorbent. Factors that influence the adsorption process studied to obtain kinetic and thermodynamic parameters include time, concentration and temperature variation of adsorption. Based on XRD characterization, the distance between layers from 7,53 ? on the Zn-Cr layered double hydroxide before intercalation to 10,26 ? on Zn-Cr layered double hydroxide intercalated with keggin ion [SiW12O40]4-. BET analysis showed that the surface area of both materials increased from 31,638 m2/g to 128,871 m2/g. The result of pH Point Zero Charge measurement for the Zn-Cr layered double hydroxide material is 10 while the Zn-Cr intercalated with keggin ion [SiW12O40]4- material is 8. Based on the kinetics model, adsorption of Cr(VI) ion follows pseudo-second-order model with a linear regression coefficient close to 1. Furthermore, the intercalation of the Zn-Cr intercalated with keggin ion [SiW12O40]4- shows the higher adsorption capacity for the Cr(VI) ion than the Zn-Cr layered double hydroxide as a control. Keywords: adsorption, Cr(VI), keggin ion, layered double hydroxide, Zn-Cr