Research on the Preparation and Turbidity Removal Efficiency of Polysilicate Iron and Zinc(PSFZn) Coagulant

2011 ◽  
Vol 233-235 ◽  
pp. 537-540
Author(s):  
Li Ping Wang ◽  
Ai Bin Xu ◽  
Xia Xu ◽  
Er Deng Du ◽  
Xiao Fei Yan

A new coagulant polysilicate iron and zinc (PSFZn) was prepared by using sodium silicate, inorganic acid, ferric chloride, zinc chloride as raw materials, the factors of (Fe+Zn):Si molar ratio, Fe:Si molar ratio, reaction temperature, reaction time and the dosage on coagulation performance were tested. The results showed that the best preparation condition of PSFZn were 60min of reaction time preparation, 30°C of temperature and 4:2:3 of n(Fe):n(Zn):n(SiO2). When the dosage was 0.4mL·L-1, the removal efficiency of turbidity was the best which could reach 98.07%. At the same time, it could be concluded that the coagulation mechanism of PSFZn was the combined action of the electric neutralization, the adsorption bridging and sticks the attachment to sweep, which was also the action of the silicic acid, the metal ions and the ions hydrolysate to the muddy colloid pellet in the simulated water sample.

2010 ◽  
Vol 154-155 ◽  
pp. 230-234 ◽  
Author(s):  
Li Ping Wang ◽  
Xiao Fei Yan ◽  
Xia Xu ◽  
Ai Bin Xu ◽  
Nai Yuan Gao

A new polyferric silicate chloride(PFSC) was prepared by using sodium silicate, ferric chloride as raw materials, at the same time, its coagulation performance and the influencing factors were observed. The water containing algae was processed by PFSC coagulant and coagulation mechanism were discussed. The results showed that the best reaction time of PFSC preparation was 1h, temperature was 40°Cand Fe/Si mole ratio was 1. The removal efficiencies of chlorophyll a and turbidity were 82.40% and 94.97% respectively at 14mgFe•L-1 of dosage. Coagulation mechanism of PFSC is considered as the cooperation of oxidization/adsorption/charge-neutralization, adsorption-bridging and sweeping, which is the effect of silicic acid, iron and iron hydrolysate on the suspended particles in wastewater.


2015 ◽  
Vol 5 (2) ◽  
pp. 177-188 ◽  
Author(s):  
Simin Li ◽  
Yongkang Lv ◽  
Zhanmeng Liu

A novel inorganic–organic composite coagulant, poly-ferric-magnesium (PFM) polydimethyldiallylammonium chloride (PDMDAAC), was prepared using FeSO4, MgSO4 and PDMDAAC as raw materials and was introduced to treat landfill leachate. The coagulation performance of the new reagent was evaluated and compared with those of other coagulants. The new reagent was characterized in terms of the analysis of ferron-timed spectroscopy, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The coagulation mechanism was investigated by measuring the ζ-potential reduction and chemical oxygen demand removal at different dosages. Coagulation experiments revealed that the new reagent exhibited better coagulation performance compared with the simple PFM and the PFM + PDMDAAC. Ferron-timed spectroscopy showed that the new reagent exhibited increased effective polymer species concentration. XRD and FTIR spectroscopy showed that the new reagent was not a simple mechanical mixing of PFM and PDMDAAC, but a composite system with inorganic–organic complex interpenetration networks. The predominant coagulation mechanism of the new reagent was charge neutralization at low dosages, as well as adsorption bridging and co-precipitation netting at high dosages, when treating landfill leachate.


2011 ◽  
Vol 298 ◽  
pp. 163-168 ◽  
Author(s):  
Yuan Yuan Lei ◽  
Guo Zheng ◽  
Yu Sun ◽  
Yong Zhou

In this paper, with fatty alcohol polyoxyethylene (AEO9), succinic anhydride (SA) and sodium hydroxide as raw materials, a new type of fatty alcohol polyoxyethylene carboxylate surfactants (SAE9C-Na) was obtained by esterification and neutralizing effect. The influencing factors were researched and its surface properties were studied. The optimum condition of synthesis was determined: molar ratio of alcohol to acid was 1:1.1, reaction temperature was 85°C, reaction time was 60 min, under this condition, the yield could reach up to 95.8%. The results received from this experiment showed that SAE9C-Na had excellent surface activity and foaming and foam stability, whose emulsification and solubility enhancement were improved greatly.


2015 ◽  
Vol 659 ◽  
pp. 216-220 ◽  
Author(s):  
Achanai Buasri ◽  
Thaweethong Inkaew ◽  
Laorrut Kodephun ◽  
Wipada Yenying ◽  
Vorrada Loryuenyong

The use of waste materials for producing biodiesel via transesterification has been of recent interest. In this study, the pork bone was used as the raw materials for natural hydroxyapatite (NHAp) catalyst. The calcination of animal bone was conducted at 900 °C for 2 h. The raw material and the resulting heterogeneous catalyst were characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and the Brunauer-Emmett-Teller (BET) method. The effects of reaction time, microwave power, methanol/oil molar ratio, catalyst loading and reusability of catalyst were systematically investigated. The optimum conditions, which yielded a conversion of oil of nearly 94%, were reaction time 5 min and microwave power 800 W. The results indicated that the NHAp catalysts derived from pork bone showed good reusability and had high potential to be used as biodiesel production catalysts under microwave-assisted transesterification of Jatropha Curcas oil with methanol.


Author(s):  
Agnieszka Wróblewska

Abstract This work presents the studies on the optimization of the process of phenol hydroxylation over the Ti-MWW catalyst. The medium of the reaction was only water introduced into the rector with the 30 wt% hydrogen peroxide (oxidizing agent) and formed during the reaction from the hydrogen peroxide. For the mathematical optimization the rotatable-uniform design was used. The main investigated technological parameters were: the temperature, the molar ratio of phenol/hydrogen peroxide, the catalyst content and the reaction time. The course of the main functions describing the process were presented in the form of layer drawings. The analysis of the layer drawings allowed to establish the most beneficial parameters for this process. Studies have shown that in water solution it is best to conduct phenol hydroxylation process at: the temperature of 93-100oC, phenol/hydrogen peroxide molar ratio 0.9-1, catalyst concentration 3-3.5 wt% and during the reaction time of 55-60 minutes. Under these conditions, it is possible to achieve phenol conversion of 85 mol%, selectivity of transformation to organic compounds in relation to phenol consumed 50 mol% and the yield of hydroquinone about 19 mol%. The phenol hydroxylation method, presented in this article, is a preferred alternative to conventional solutions, as it is more environmentally and cost-effective, taking into account consumption of raw materials and energy.


2011 ◽  
Vol 66-68 ◽  
pp. 65-69
Author(s):  
Long Feng Li ◽  
Yuan Gao ◽  
Mao Lin Zhang

Ca-Mg-Al hydrotalcite-like compounds (CaMgAl-HTLcs) were synthesized by a hydrothermal method, and characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential thermal analysis (DTA) techniques. The effects of the medium pH value, the molar ratio of the raw materials, the reaction temperature and the reaction time on the structure of CaMgAl-HTLcs were studied. The results showed that increasing treatment temperature and reaction time could improve the crystallinity and monodispersity of hydrotalcite-like compound particles. And well-defined CaMgAl-HTLcs could be prepared at a pH value of 10~11 with n(Zn+Mg+Ca):n(Al) =2. The products synthesized were applied to PVC to improve the thermal stability of PVC.


2020 ◽  
Author(s):  
◽  
B. G. Bessa

Brazil is a country with several options of energetic matrices, due to its favorable climatic conditions, availability of land for cultivation of different cultures, oil reserves, amongst many other alternative sources of raw materials that can be used as fuel. Biodiesel is an example of energy used in the transport sector and derived from renewable sources, such as vegetable and animal oils and fats It is generally produced using methanol as transesterifying agent in homogeneous catalysis with a base. This type of catalysis, however, generates waste due to the need to wash the generated biodiesel, in order to meet the product quality standards. Therefore, there is a need to develop different production routes that are more economical and that use catalysts that are easier to separate and recover, enabling their reuse. In this work we studied the methyl transesterification reaction of soybean oil with the anion exchange resin, Amberlyst®, as a heterogeneous catalyst. This reaction was conducted using the 9:1 molar ratio of alcohol/oil, 50 ºC, ambient pressure and 300 rpm of stirring. We studied the effects of the load of catalyst used, reaction time, previous drying of the resin, and the amount of added solvent. The first experiment showed a peak of conversion rate using 2,5% of resin, by mass and in relation to oil, resulting in 1,04 ± 0,01% after 90 minutes of reaction. However, an increase was noticed when the resin was dried at 50 ºC, in order to remove residual water from its pores, obtaining the result of 2,42 ± 0,01% at the same reaction time of 90 min. For longer reaction times there was no considerable improvement in conversion. In order to verify the influence of the presence of cosolvent in the reaction, (n-hexane), four different amounts of it were used (mass ratio of cosolvent in relation to mass of oil was 0.5, 0.6, 0.8 and 1), keeping constant the other conditions of the reaction. All the proportions of cosolvent resulted in increased conversion when compared to previous experiments. The highest conversion obtained was 53,66 ± 0,02% using 0,8 mass ratio of cosolvent. In conclusion, we observed the necessity of drying the resin before it is used in the reaction, and that the use of cosolvent helps to increase the conversion. The analysis via MEV showed that the resin particle is spherical and that its surface is plain, without great variation when it was in natura or dried


2014 ◽  
Vol 906 ◽  
pp. 178-182
Author(s):  
Yang Xiao ◽  
Zhen Zhu Cao ◽  
Ru Yi Shao ◽  
Wei Yan He ◽  
Yan Fang Gao ◽  
...  

The precursor of bismuth ferrite BiFeO3 powders were prepared by the normal co-precipitation and reversed co-precipitation method. The key influencing factors including the reaction time, the concentration of mineralizer and the molar ratio of raw materials in the normal co-precipitation are systematically studied. Pure BiFeO3 powder has been obtained by adjusting the molar ratio of raw materials. Based on the results of the normal co-precipitation, a simple reversed co-precipitation process has been developed.


2012 ◽  
Vol 550-553 ◽  
pp. 400-403 ◽  
Author(s):  
Xue Nan Sun ◽  
Li Cui ◽  
Tong Kuan Xu ◽  
Da Zhi Wang

Benzaldehyde 1, 2-propanediol acetal was synthesized from benzaldehyde and 1, 2-propanediol in the presence of ionic liquid [HMIM]HSO4. The effect of the amount of catalyst, reaction time, reaction temperature, and the molar ratio of raw materials agent on the product yield was investigated respectively. Experimental results demonstrate that ionic liquid [HMIM]HSO4is a good catalyst for preparation of benzaldehyde 1, 2-propanediol acetal. Results showed the optimal reaction conditions are as follows: the mole ratio of benzaldehyde to 1, 2-propanediol is 1:1.3, the amount of catalyst is 3.0g, the reaction temperature is 343K, and the reaction time is 4h. The achieved yield of acetal is 78. 7%.


2013 ◽  
Vol 781-784 ◽  
pp. 283-286
Author(s):  
Xiang Wen Kong ◽  
Han Wang ◽  
Zhao Jing Li ◽  
Jing Zhang

Cyclohexyl ferulate was prepared by direct sterification of ferulic acid and cyclohexanol as raw materials with sodium bisulfate supported by silica as a catalyst. The influences of some factors on the synthesis process were studied. The optimal reaction conditions based upon 0. 2 mol of ferulic acid were chosen that the molar ratio of cyclohexanol and ferulic acid was 10 : 1, the mass ratio of catalyst to reactants was 5%, refluing reaction time was 3.5 hours, et a1. The yield of the product reached 80%. The structure of the product was characterized by IR, 1H NMR and MS spectrum. The catalyst could be recycled and used for many times, which is friendly to the environment.


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