Utilization of Sludge from Sidoarjo Mudflow for Zeolite Synthesis

2014 ◽  
Vol 1024 ◽  
pp. 263-266 ◽  
Author(s):  
Chris Salim ◽  
Niki Prastomo ◽  
Yan Shao ◽  
Hirofumi Hinode

Sidoarjo mudflow occurred in 2006 has been causing major environmental problems in a wide area surrounding the region. The utilization of the sludge from this mudflow as useful materials is a potential solution to this problem. In this study, we proposed a hydrothermal treatment method to convert the silica-rich sludge into zeolites useful as adsorbent for inorganic pollutants such as heavy metals. Prior to the hydrothermal treatment, the sludge was contacted with NaOH solution in a teflon vessel. During the hydrothermal treatment, the mixture was subjected to increasing temperature for a certain period of time. After hydrothermal treatment, the solid phase was filtered, washed thoroughly until neutral pH and dried. In this study, we evaluated the effect of NaOH concentration and hydrothermal treatment temperature on the type of zeolite formed. The surface morphology and composition of prepared zeolite was characterized by SEM-EDS while the type of zeolite was determined by XRD analysis. Preliminary study of the adsorption ability of the zeolites towards metal ions was carried out by CEC measurement using sodium acetate method.

Fermentation ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 81
Author(s):  
Hironaga Akita ◽  
Mohd Zulkhairi Mohd Yusoff ◽  
Shinji Fujimoto

Malaysia is the second largest palm oil producer and exporter globally. When crude palm oil is produced in both plantations and oil processing mills, a large amount of oil palm empty fruit bunch (OPEFB) is simultaneously produced as a waste product. Here, we describe the preparation of hydrolysate from OPEFB. After OPEFB was hydrothermally treated at 180–200 °C, the resultant liquid phase was subjected to high-performance liquid chromatography analysis, while the solid phase was used for acidic and enzymatic hydrolysis. Hemicellulose yield from the acid-treated solid phase decreased from 153 mg/g-OPEFB to 27.5 mg/g-OPEFB by increasing the hydrothermal treatment temperature from 180 to 200 °C. Glucose yield from the enzyme-treated solid phase obtained after hydrothermal treatment at 200 °C was the highest (234 ± 1.90 mg/g-OPEFB, 61.7% production efficiency). In contrast, xylose, mannose, galactose, and arabinose yields in the hydrolysate prepared from the solid phase hydrothermally treated at 200 °C were the lowest. Thus, we concluded that the optimum temperature for hydrothermal pretreatment was 200 °C, which was caused by the low hemicellulose yield. Based on these results, we have established an effective method for preparing OPEFB hydrolysates with high glucose content.


2017 ◽  
Vol 889 ◽  
pp. 229-233
Author(s):  
Nur Arifah Ismail ◽  
Mohd Hasmizam Razali ◽  
Khairul Anuar ◽  
Mat Amin

In this research, the effect of different hydrothermal treatment temperature (100, 150, and 200 °C) on the products obtained by hydrothermal method was studied. Various characterization techniques was carried out such as X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), energy dispersive of x-ray spectroscopy (EDX) and fourier transform infrared spectroscopy (FTIR). XRD analysis shows that titanate phase was formed at 150 and 200 °C hydrothermal treatment. On the other hand, at 100 °C anatase TiO2 phase structured was gained which is similar with the TiO2 precursor. Morphological study using FESEM revealed that nanofibers and nanorods samples obtained at 150 °C and 200 °C, respectively. At 100°C, irregular shaped particle was attained similar with TiO2 precursors. FTIR spectra for the all studied sample displayed three main broad peaks at the range of 3700-2800, and 1800-1400 assigned to –OH stretching and deformation mode due to H2O molecules and M-O stretching mode at 900-400 cm-1 assigned to Ti-O bond.


Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 140
Author(s):  
Aaron Mbissik ◽  
Abdellatif Elghali ◽  
Muhammad Ouabid ◽  
Otmane Raji ◽  
Jean-Louis Bodinier ◽  
...  

Due to the increasing demand for conventional sources of potassium (K) and their inaccessibility by African countries, K-rich igneous rocks are increasingly studied as potential alternative sources. In this study, six potassic igneous rocks (syenites and trachytes) from the Tamazeght, Jbel Boho, Ait Saoun, and El Glo’a regions (Morocco) were sampled and characterized. Then they were hydrothermally treated to enhance their K release for potential use as potassic fertilizers. The raw materials are mainly formed by microcline (up to 74%), orthoclase (20–68%), albite (36–57%), biotite-muscovite (15–23%), and titanite, calcite, hematite, and apatite as accessory minerals. These samples were crushed and milled to reach a particle size <150 µm and mixed with 4 N NaOH solution in an autoclave. The liquid/solid (L/S) ratio was about 44 mL/50 g. The powders were allowed to react with the solution at 170 °C for 7 h. For all tests, NaOH reacted completely with the powders and no liquid was observed after the treatment. X-ray diffraction (XRD), thermal gravimetric analysis (TGA), infrared spectroscopy (IRTF), and scanning electron microscopy (SEM-EDS) were carried out on treated samples to characterize the mineralogical and structural changes due to the alkali-hydrothermal treatment. Indeed, the treated samples revealed the presence of sodic neoformed phases such as thermonatrite, sodalite, analcime, and cancrinite. The treated material was leached for a week using deionized water and the elements released were measured using inductively coupled plasma–atomic emission spectroscopy (ICP-AES). The hydrothermal process showed a strong effect on structure breakdown as well as on the release of K and other nutrients such as P, Fe, Si, Mg, and Ca. Therefore, the alkali-hydrothermal treatment allowed the release of 50.5 wt% K. Moreover, the release of Mg, Ca, Fe, P, K, and Si were significantly increased. Mg, Ca, Fe, P, K, and Si release within raw materials was about (0.5–3.6), (3.5–31.4), (0.01–0.4), (0.01–0.3), (20–55), and (4.6–8) mg/kg, respectively, whereas treated samples showed a higher release of these elements. Quantitatively, Mg, Ca, Fe, P, K, and Si releases were about (10–11.8), (60–70), (7–20), (1.2–15), (218–1278), and (1119–2759) mg/kg, respectively. Consequently, the treated igneous rocks (syenite and trachyte) could be directly used as potassic fertilizers that would also be a source of other nutrients.


2017 ◽  
Vol 105 (12) ◽  
Author(s):  
Keun-Young Lee ◽  
Jimin Kim ◽  
Maengkyo Oh ◽  
Eil-Hee Lee ◽  
Kwang-Wook Kim ◽  
...  

AbstractMetal ferrocyanides (MFCs) have been studied for many years and are regarded as efficient adsorbents for the selective removal of radioactive cesium (Cs) from contaminated aqueous solutions. Although their efficiency has been demonstrated, various investigations on the physicochemical, thermal, and radiological stability of the solids of MFCs are required to enhance the applicability of MFCs in the treatment process. We observed that the Cs adsorption efficiencies of cobalt and nickel ferrocyanides decreased as their aging period increased, while the Cs adsorption efficiencies of copper and zinc ferrocyanides did not decrease. The tendencies of these ferrocyanides were accelerated by exposure of the solids at a higher temperature for a longer time. Our comprehensive analyses demonstrated that only the oxidizable metals in the MFCs can be oxidized by aging time and increasing temperature; also, this affects the Cs removal efficiency by decreasing the exchangeable sites in the solids. The chemical stability of MFCs is very important for the optimization of the synthesis and storage conditions.


2019 ◽  
Vol 8 (3) ◽  
pp. 234
Author(s):  
Nasr Hadi ◽  
Tajdine Lamcharfi ◽  
Farid Abdi ◽  
Nor-Said Echtoui ◽  
Ahmed Harrach ◽  
...  

<p class="Abstract"><span lang="EN-US">The influences of calcination temperature and doping with cobalt in A–site on structural and dielectric properties of CaCu<sub>3-x</sub>Co<sub>x</sub>Ti<sub>4</sub>O<sub>12</sub> (CCCxTO, x = 0.00, 0.02 and 0.10) ceramics sintered at 1050 <sup>0</sup>C for 8h were investigated. The ceramic samples are prepared by the conventional solid-state method using high purity oxide powders, and they are calcined at 850 °C, 950 °C and 1050 <sup>0</sup>C for 4h. The X-ray diffraction (XRD) analysis of pure and doped CCTO samples calcined at 950 °C and 1050 <sup>0</sup>C showed no traces of any other secondary phases, while impurity phases alongside CCTO phase in the x=0.00 sample calcined at 850 <sup>0</sup>C was observed. Scanning electron microscopy (SEM) investigation showed an increase in grain size with increasing of Co content and calcining temperature. Dielectric measurements indicated that the dielectric constant of the pure CCTO calcined at 1050 <sup>0</sup>C/4h has a low value in the frequency range of 1kHz up to 1MHz, whereas the substitution of Co up to x = 0.10 into CCTO caused a huge increase in the dielectric constant value of the calcined samples which is equal to 153419 and 18957 at 950 <sup>°</sup>C and 1050 <sup>0</sup>C respectively. The complex impedance analysis of all samples shows a decrease in resistance with an increasing temperature, which suggests a semiconductor nature of the samples.</span></p>


Author(s):  
Olivier Walusinski

Although the framework of neurological nosography was established during the second half of the nineteenth century, with Jean-Martin Charcot and his Salpêtrière School playing a major role, therapies for the recently identified diseases remained relatively ineffective. Since many Parkinson’s patients reported an improvement in their condition after being violently shaken during travel in mail carriages, Charcot recycled an old treatment method based on a vibratory armchair, assigning the preliminary study to Gilles de la Tourette, who tried to extend the technique to other pathologies by using a vibratory helmet. Another technique recommended by Charcot for treating tabes patients was “suspension,” thought to elongate the spinal cord. The related therapeutic tests in France and Europe are discussed in detail. Gilles de la Tourette made significant use of suspension at the time. The author compares his reports with the scientific challenges to his techniques and examines the resulting discussions.


2021 ◽  
Vol 406 ◽  
pp. 126656
Author(s):  
Daihua He ◽  
Xuexian Zhang ◽  
Ping Liu ◽  
Xinkuan Liu ◽  
Xiaohong Chen ◽  
...  

Author(s):  
Haixia Wang ◽  
Mingliang Zhang ◽  
Qi Lv

The influence of pyrolysis temperature on cadmium (Cd) removal capacity and mechanisms by maize straw biochars (MSB) and Platanus leaves biochars (PLB) pyrolyzed at 300, 400, 500 and 600 °C was investigated. The results showed that the biochars pyrolyzed at 500 °C had the highest adsorption capacity for Cd, and the maximum adsorption at pH 5.0 was 35.46 mg/g and 25.45 mg/g for MSB and PLB, respectively. The increase in adsorption efficiency with increasing temperature indicated that the adsorption of Cd onto the biochars was endothermic. Based on the balance analysis between cations (Ca2+ and Mg2+) released and Cd adsorbed onto biochar in combination with SEM-EDX, FTIR, and XRD analysis, it was concluded that cation exchange, complexation with surface functional groups, precipitation with minerals (CdCO3), and coordination with π electrons were the dominant mechanisms responsible for Cd adsorption by MSB. With the pyrolysis temperature increasing from 300 to 600 °C, the contribution of cation exchange (Ca2+ and Mg2+) on Cd removal by MSB decreased from 37.4% to 11.7%, while the contribution of precipitation with Otavite (CdCO3) and Cd2+-π electrons interaction increased. For PLB, the insoluble Cd minerals were not detected by XRD, and the contribution of cation exchange had no significant difference for PLB pyrolyzed at 300, 400, 500 and 600 °C.


2019 ◽  
Vol 285 ◽  
pp. 146-152
Author(s):  
Nai Yong Li ◽  
Han Xiao ◽  
Chi Xiong ◽  
De Hong Lu ◽  
Rong Feng Zhou

The semi-solid extruded ZCuSn10P1 copper alloy were annealed at different temperatures and time. The influences of heat treatment temperature and holding time on the microstructure of semi-solid ZCuSn10P1 copper alloy were investigated. The results show that with the increase of heat treatment temperature, the morphology of the semi-solid microstructure was improved, the sharp angle around the primary phase α-Cu and the liquid droplets were reduced. With the increase of heat treatment time, the solid-liquid segregation of the semi-solid structure was improved. The average grain size of the solid phase increased with the increasing of the holding time. After heat treatment, the solid solubility of the primary phase α-Cu increased, and the Sn and P elements in the liquid phase continued to diffuse to the primary phase α-Cu. The microstructure of semi-solid copper alloy was the most uniform after heat treatment at 350°C for 120 min.


Sign in / Sign up

Export Citation Format

Share Document