scholarly journals Red Mud-Based Polyaluminum Ferric Chloride Flocculant: Preparation, Characterization and Flocculation Performance

2021 ◽  
Author(s):  
Yong Cheng ◽  
Longjun Xu ◽  
Chenglun Liu ◽  
Zao Jiang ◽  
Qiyuan Zhang ◽  
...  
Keyword(s):  
Red Mud ◽  
High Efficiency ◽  
Low Cost ◽  
Oxygen Demand ◽  
Industrial Applications ◽  
Iron Chloride ◽  
Raw Material ◽  
Molar Ratio ◽  
Polymerization Temperature ◽  
Solution Ph

Abstract In this work, red mud was used as raw material to extract Al and Fe with hydrochloric acid. The high-efficiency polyaluminum iron chloride (PAFC) flocculant was prepared via adjusting the pH of the leaching solution, the molar ratio of aluminum and iron, and the polymerization temperature. The effect of synthesis and flocculation conditions on the flocculation performance of aged landfill leachate was investigated. The results confirmed that the PAFC prepared at the polymerization pH of 2.5, the Al/Fe molar ratio of 8, and the polymerization temperature of 70 °C had the optimum flocculation effect. The flocculation consequences of PAFC and commercial polyaluminum iron chloride flocculant (CPAFC) under different flocculation conditions were compared. The chemical oxygen demand (COD), UV254, chroma and settlement height of PAFC at flocculant concentration of 60 g/L and solution pH of 6 were 72.2%, 79.2%, 82.9% and 9.5 cm (within 90 min), respectively. PAFC has excellent flocculation performance and can be used as a simple, potentially low-cost wastewater treatment agent in industrial applications.

scholarly journals Synthesis of Nd-doped ZSM-5 and its application to treating slightly polluted water

2017 ◽  
Vol 8 (1) ◽  
pp. 86-93
Author(s):  
Mang Lu ◽  
Lin He ◽  
Yue Cheng
Keyword(s):  
Contact Time ◽  
Oxygen Demand ◽  
Raw Material ◽  
Molar Ratio ◽  
Polluted Water ◽  
Solution Ph ◽  
Experimental Conditions ◽  
Factors Influencing ◽  
Orthogonal Experiments ◽  
Removal Efficiencies

Abstract In this study, ZSM-5 zeolite was synthesized using diatomaceous mud as the raw material, and then doped with different amounts of Nd2O3. The orthogonal experiments were performed to investigate the influence of Nd:Si molar ratio, zeolite dosage, contact time, solution pH and temperature on the removal of humic acid (HA). The removal of HA was comprehensively evaluated by chemical oxygen demand (COD), UV254 and UV410 of the solution. The results demonstrate that solution pH and zeolite dosage are the two most important factors influencing HA adsorption. The optimum experimental conditions were determined to be: 35 °C, Nd:Si molar ratio of 1:100, 2.0 g/L zeolite, pH 4 and 50 min contact time. Under these conditions, the removal efficiencies of UV254, UV410 and COD are 82.70%, 76.00% and 82.10%, respectively, corresponding to a comprehensive removal of 81.02%.

Immobilization of Eversa Lipases on Hydrophobic Supports for Production of Oleate Esters Solvent-Free

2021 ◽  
Author(s):  
Gloria Fernandez-Lorente ◽  
Daniela Remonatto ◽  
J. Vladimir Oliveira ◽  
J. Manuel Guisan ◽  
Débora Oliveira ◽  
...  
Keyword(s):  
Sunflower Oil ◽  
Low Cost ◽  
Industrial Applications ◽  
Solvent Free ◽  
Molar Ratio ◽  
High Catalytic Activity ◽  
Promising Alternative ◽  
Highly Active ◽  
Immobilized Biocatalyst ◽  
Hydrophobic Supports

Abstract Lipases are an important group of biocatalysts for many industrial applications. Two new commercial low-cost lipases Eversa® Transform and Eversa® Transform 2.0 was immobilized on four different hydrophobic supports: Lewatit-DVB, Purolite-DVB, Sepabeads-C18, and Purolite-C18. The performance of immobilized lipases was investigated in the transesterification of sunflower oil solvent-free in an anhydrous medium. Interesting results were obtained for both lipases and the four supports, but with Sepabeads support the lipases Eversa showed high catalytic activity. However, the more stable and efficient derivative was Eversa® Transform immobilized on Sepabeads C-18. A 98 wt% of ethyl ester of fatty acid (FAEE) was obtained, in 3 hours at 40ºC, ethanol/sunflower oil molar ratio of 3:1 and a 10 wt% of the immobilized biocatalyst. After 6 reaction cycles, the immobilized biocatalyst preserved 70 wt% of activity. Both lipases immobilized in Sepabeads C-18 were highly active and stable in the presence of ethanol. The immobilization of Eversa Transform and Eversa Transform 2.0 in hydrophobic supports described in this study appears to be a promising alternative to the immobilization and application of these news lipases still unexplored.

Nickel-Catalyzed Reductive Monofluoroakylation of Alkyl Tosylate with Bromofluoromethane to Access Primary Alkyl Fluoride

2021 ◽  
Author(s):  
Ru Cui ◽  
Jie Sheng ◽  
Bing-Bing Wu ◽  
Duo-Duo Hu ◽  
Hong-Qian Zheng ◽  
...  
Keyword(s):  
Functional Group ◽  
High Efficiency ◽  
Low Cost ◽  
Raw Material ◽  
Mild Conditions

A nickel-catalysed direct terminal monofluormethlyation between alkyl tosylates and a low-cost, industrial raw material bromofluoromethane has been developed. This transformation has demonstrated high efficiency, mild conditions, and good functional-group compatibility....

Current scenario of catalysts for biodiesel production: a critical review

2018 ◽  
Vol 34 (2) ◽  
pp. 267-297 ◽  
Author(s):  
Farrukh Jamil ◽  
Lamya Al-Haj ◽  
Ala’a H. Al-Muhtaseb ◽  
Mohab A. Al-Hinai ◽  
Mahad Baawain ◽  
...  
Keyword(s):  
Heterogeneous Catalysts ◽  
Low Cost ◽  
Bifunctional Catalyst ◽  
Raw Material ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Homogeneous Catalysts ◽  
Animal Fats ◽  
Current Scenario ◽  
Short Chain Alcohol

AbstractDue to increasing concerns about global warming and dwindling oil supplies, the world’s attention is turning to green processes that use sustainable and environmentally friendly feedstock to produce renewable energy such as biofuels. Among them, biodiesel, which is made from nontoxic, biodegradable, renewable sources such as refined and used vegetable oils and animal fats, is a renewable substitute fuel for petroleum diesel fuel. Biodiesel is produced by transesterification in which oil or fat is reacted with short chain alcohol in the presence of a catalyst. The process of transesterification is affected by the mode of reaction, molar ratio of alcohol to oil, type of alcohol, nature and amount of catalysts, reaction time, and temperature. Various studies have been carried out using different oils as the raw material; different alcohols (methanol, ethanol, butanol); different catalysts; notably homogeneous catalysts such as sodium hydroxide, potassium hydroxide, sulfuric acid, and supercritical fluids; or, in some cases, enzymes such as lipases. This article focuses on the application of heterogeneous catalysts for biodiesel production because of their environmental and economic advantages. This review contains a detailed discussion on the advantages and feasibility of catalysts for biodiesel production, which are both environmentally and economically viable as compared to conventional homogeneous catalysts. The classification of catalysts into different categories based on a catalyst’s activity, feasibility, and lifetime is also briefly discussed. Furthermore, recommendations have been made for the most suitable catalyst (bifunctional catalyst) for low-cost oils to valuable biodiesel and the challenges faced by the biodiesel industry with some possible solutions.

A Low Cost ZSM-5 Zeolite Obtained from Rice Hull Ash

2005 ◽  
Vol 498-499 ◽  
pp. 676-680 ◽  
Author(s):  
A.A. Fernandes ◽  
E.U.C. Frajndlich ◽  
Humberto Gracher Riella
Keyword(s):  
Large Scale ◽  
High Efficiency ◽  
Low Cost ◽  
Amorphous Structure ◽  
Industrial Applications ◽  
Rice Hull ◽  
Rice Hull Ash ◽  
Industry Waste ◽  
Pure Silica ◽  
Zeolite Formation

The high pure synthetic zeolite have a large application in industry and agriculture, being nowadays in majority imported in Brazil. The biomass like rice hull ash (RHA), a rice industry waste, can be real advantageous in manufacture of different materials, since that is produced in large scale in the country. The silica extraction from RHA by alkaline leaching is a low energetic coast process and high efficiency, obtaining high pure silica with high reactive amorphous structure, very interesting for zeolite production. In this work was developed a economically feasible route for the production of high purity and crystallinity ZSM-5 zeolite, free of expensive template, starting from a low value intake, a industrial waste, producing a high value materials. The extracted silica from RHA in sodium silicate form is precipitated in the proper zeolite formation reactional mixture. The ZSM-5 have a lot of industrial applications due your high selectivity in catalytic reactions and high thermal and acid stability.

Sugar beet pulp as biomass

2017 ◽  
pp. 29-32 ◽  
Author(s):  
Kazm Eber Özba ◽  
Özen Özboy Özba
Keyword(s):  
Sugar Beet ◽  
Animal Feed ◽  
Sugar Industry ◽  
Low Cost ◽  
Industrial Applications ◽  
Single Cell Protein ◽  
Sugar Beet Pulp ◽  
Raw Material ◽  
Cell Protein ◽  
Beet Pulp

The sugar beet industry produces considerable amounts of organic waste and by-products. Sugar beet pulp (SBP) is the residue that remains after sugar extraction. SBP is a lignocellulosic by-product of the sugar industry and generally used as animal feed at relatively low price. Instead of cattle feeding, SBP can be used as a raw material for industrial applications because it is low-cost and available in large amounts. Biomass is a clean and renewable energy source. The use of SBP for the production of ethanol, methanol, single cell protein, biofuels etc. is economically very attractive. This literature review evaluates the use of SBP as biomass.

scholarly journals Cleaner Production Assessment of Fast Bordeaux GP Base

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Mausumi Mukhopadhyay ◽  
Rashmita D. Patel
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Chemical Oxygen Demand ◽  
Pilot Plant ◽  
Oxygen Demand ◽  
Feasibility Studies ◽  
Cleaner Production ◽  
Raw Material ◽  
Molar Ratio ◽  
High Chemical Oxygen Demand

The pilot plant study of cleaner production (CP) process of a dyes intermediate, Fast Bordeaux GP Base (2-nitro-p-anisidine), is presented in this work. The existing production process with acetic anhydride as raw material generates highly polluting (high chemical oxygen demand), huge-volume effluent, and thus the treatment is expensive. In the proposed process, raw material acetic anhydride in acetylation step is replaced with acetic acid. The reaction conditions like reaction time (3 h), temperature (120∘C) and molar ratio of p-anisidine and acetic acid (1 : 3.58) are optimized in the laboratory scale and implemented in pilot plant. The extent of conversion has been monitored by nitrite value test, and purity of product mixture is measured with thin-layer chromatography (TLC). The acidic wastewater quantity is dramatically reduced by incorporating recycling in washing scheme, and thus water consumption is reduced. Reduction in wastewater generation and reduction/elimination of treatment cost is also observed. Chemical oxygen demand (COD) of the effluent stream is reduced by the recovery of by-products sodium acetate and spent acid. The technoeconomical feasibility studies show that the proposed CP options are highly economical and environmental friendly.

scholarly journals Synergistic Degradation of Dye Wastewaters Using Binary or Ternary Oxide Systems with Immobilized Laccase

Catalysts ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 402 ◽  
Author(s):  
Katarzyna Antecka ◽  
Jakub Zdarta ◽  
Katarzyna Siwińska-Stefańska ◽  
Grzegorz Sztuk ◽  
Ewelina Jankowska ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
High Efficiency ◽  
Dye Degradation ◽  
Oxygen Demand ◽  
Molar Ratio ◽  
Process Conditions ◽  
Ternary Oxide ◽  
Reactive Black 5 ◽  
Oxide Systems ◽  
Alizarin Red

In recent years, groundwater contamination caused by dyes has become an important problem. They enter into wastewater as a result of the textile, automotive, or cosmetics industries. For this reason, new methods are being sought, which would aid at the removal of dye impurities with high efficiency and also would be relatively cheap. In the presented study synthesized TiO2-ZrO2 (with TiO2:ZrO2 molar ratio of 8:2) and TiO2-ZrO2-SiO2 (with TiO2:ZrO2:SiO2 molar ratio of 8:1:1) oxide materials were used as supports for enzyme immobilization. Effective synthesis of the carriers was confirmed by results of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), low-temperature nitrogen sorption and Fourier transform infrared spectroscopy (FTIR). The materials achieve high immobilization efficiency of the laccases from Trametes versicolor (83% and 96% for TiO2-ZrO2-laccase and TiO2-ZrO2-SiO2-laccase, respectively). The effect of selected dye concentrations, pH, temperature, and reusability were also tested. The obtained results showed that after removal of textile dyes, such as Alizarin Red S (ARS), Remazol Brilliant Blue R (RBBR), and Reactive Black 5 (RB5), under optimal process conditions, which were pH 5 and 25 °C, from dye solution of 5 mg/L degradation efficiency reached 100%, 91%, and 77%, respectively, suggesting synergistic mechanism of degradation by simultaneous sorption and catalytic action. Finally, reduction of chemical oxygen demand (COD) of the solution after treatment indicated lower mixture toxicity and effective dye degradation.

scholarly journals A State of the Art of the Multilevel Inverters with Reduced Count Components

Electronics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1924
Author(s):  
Alaaeldien Hassan ◽  
Xu Yang ◽  
Wenjie Chen ◽  
Mohamad Abou Houran
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
Academic Research ◽  
Industrial Applications ◽  
Research Field ◽  
Optimum Number ◽  
Multilevel Inverters ◽  
Pros And Cons ◽  
Long Lifetime ◽  
Switching Devices

Multilevel inverters (MLIs) have become a trend in the field of DC/AC inverters and one of the main requirements in many of the industrial applications. MLIs spread in the academic research field and replaced the conventional inverters due to the several advantages that these topologies presented over the conventional inverters, as follows. (1) Operate with a high number of steps in the output voltage waveform, which helps in reducing the level of harmonics and presents fine and clear waveforms; furthermore, reduce the voltage stress on the switching devices and gives it a long lifetime and more reliability. (2) MLIs have a low rating of the switching devices, which has a noticeable role in reducing the system cost. (3) MLIs can be operated at both higher and lower switching frequencies, which reduces the level of power losses and enhances the overall efficiency. The main problem that faces the researchers in the multilevel inverters field is to design a topology that uses the optimum number of components to ensure the low cost and obtain a high efficiency. This paper presents a description of different topologies of MLIs that were investigated in the last two decades to show the pros and cons of each topology. Also a set of performance parameters that were used to measure the effectiveness of the MLI topologies have been discussed.

scholarly journals Expression and Characterization of a GH16 Family β-Agarase Derived from the Marine Bacterium Microbulbifer sp. BN3 and Its Efficient Hydrolysis of Agar Using Raw Agar-Producing Red Seaweeds Gracilaria sjoestedtii and Gelidium amansii as Substrates

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 885
Author(s):  
Ren Kuan Li ◽  
Xi Juan Ying ◽  
Zhi Lin Chen ◽  
Tzi Bun Ng ◽  
Zhi Min Zhou ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
High Efficiency ◽  
Specific Activity ◽  
Low Cost ◽  
Intermediate Stage ◽  
Industrial Applications ◽  
Carbohydrate Binding ◽  
Gelidium Amansii ◽  
Red Seaweeds ◽  
Hydrolysis Of

Agarases catalyze the hydrolysis of agarose to oligosaccharides which display an array of biological and physiological functions with important industrial applications in health-related fields. In this study, the gene encoding agarase (Aga-ms-R) was cloned from Microbulbifer sp. BN3 strain. Sequence alignment indicated that Aga-ms-R belongs to the GH16 family and contains one active domain and two carbohydrate binding module (CBM) domains. The mature Aga-ms-R was expressed successfully by employing the Brevibacillus system. Purified rAga-ms-R was obtained with a specific activity of 100.75 U/mg. rAga-ms-R showed optimal activity at 50 °C and pH 7.0, and the enzyme activity was stable at 50 °C and also over the pH range of 5.0–9.0. After exposure of rAga-ms-R to 70 °C for 30 min, only partial enzyme activity remained. Thin layer chromatographic analysis of the enzymatic hydrolysate of agar obtained using rAga-ms-R disclosed that the hydrolysate comprised, in a long intermediate-stage of the hydrolysis reaction, mainly neoagarotetraose (NA4) and neoagarohexaose (NA6) but ultimately, predominantly neoagarotetraose and trace amounts of neoagarobiose (NA2). Hydrolysates of the raw red seaweeds Gracilaria sjoestedtii and Gelidium amansii, produced by incubation with rAga-ms-R, were mainly composed of neoagarotetraose. The results demonstrate the high efficiency of rAga-ms-R in producing neoagaraoligosaccharide under low-cost conditions.

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