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Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 463
Author(s):  
Charles Bronzo B. Farias ◽  
Rita de Cássia F. Soares da Silva ◽  
Fabíola Carolina G. Almeida ◽  
Attilio Converti ◽  
Valdemir A. dos Santos ◽  
...  

In the industries across the petroleum chain and those involved in energy generation, the use of petroderivatives as fuel oils is common. To clean parts, equipment and environments contaminated by hydrocarbons, they use expensive, toxic products, bringing risks to the environment as well as to workers’ health. Thus, the aim of this study was to check the stability of a biodetergent prepared using atoxic substances for large-scale production and industrial energy sector application. The relationship between volume (4 to 10 L) and stirring time (5 to 10 min) of the formulation at 3200 rpm and 80 °C was evaluated. The hydrophilic lipophilic balance (HLB), long-term stability (365 days), toxicity and efficiency of low-sulfur, viscous fuel oil removal from metal pieces and floors were investigated. The interaction among operating conditions was shown to influence the features of the product, which achieved approximately 100% stability after a stirring time of 7 min. The emulsion HBL index varied between 4.3 and 11.0. The biodetergent maintained its physicochemical properties during its 365 days of storage and showed high efficiency, removing 100% of the OCB1 impregnated on the metallic surfaces and floors tested. The formulation showed reliability in scale up when submitted to the study of physicochemical factors in the productive process, and safe application, by reducing risks for workers’ health and environment.


2022 ◽  
Vol 2152 (1) ◽  
pp. 012045
Author(s):  
Lan Ma ◽  
Weijie Lian ◽  
Huiming Wu ◽  
Lijun Zhang ◽  
Yuxin Zhai

Abstract The treating fluid in the piston of inner-cooling oil channel is acid wastewater containing copper ion, it would adversely affect the aquatic ecosystem when emission directly. This paper use magnesium hydroxide as a wastewater treatment agent, to study the effect of magnesium hydroxide dose, stirring time, temerature on the results of treating fluid treatment, and get the best treatment conditions. The results indicate that magnesium hydroxide has an excellent performance including easy operation, super removing rate, supernatant can meet emission standards: c(Cu2+)≤2mg/L.


2021 ◽  
Vol 14 (4) ◽  
pp. 2073-2083
Author(s):  
Kamilia Qudsiani ◽  
Sutriyo Sutriyo ◽  
Ratika Rahmasari

Nucleoside analogue antiviral remdesivir works by inhibiting the RNA-dependent RNA polymerase enzyme and terminating the viral replication. Currently, remdesivir is under a clinical trial for its activity against SARS-CoV-2. In the blood, remdesivir will undergo an enzymatic reaction to become monophosphate analogue form which is difficult to penetrate into the cell membrane. PAMAM (polyamidoamine) dendrimer is a good carrier to encapsulate remdesivir as a water-insoluble drug (0,339 mg/mL). Entrapment of remdesivir in the PAMAM cavity avoided remdesivir molecules to not undergo the enzymatic reactions. This study aimed to synthesize, characterize and evaluate cellular uptake of PAMAM-Remdesivir conjugate. PAMAM-Remdesivir was prepared with various stirring times (3, 6, 12, 24, and 48 hours). The conjugates were characterized to observe the size and particle distribution using Particle Size Analyzer, encapsulating efficiency using UV-Vis Spectroscopy, interaction between PAMAM and remdesivir particle using Fourier Transform Infrared Spectroscopy and cellular uptake of PAMAM-RDV using Fluorescence Microscope. The optimized stirring time of PAMAM-Remdesivir conjugate was 24 hours wich resulted the particles charge of + 23,07 mV of zeta potential, 1008 nm of particle size, 0,730 of PDI, and 69% entrapment efficiency. In addition, the FTIR analysis showed that remdesivir molecules successfully conjugated to PAMAM. Thus, through strring optimization time, the remdesivir molecules were successfully entrapped to PAMAM cavity. The cellular uptake in Vero Cell of PAMAM-RDV conjugated fluorescein isothiocyanate was observed with fluorescence microscope and had a stronger intensity than remdesivir only solution.


2021 ◽  
Vol 7 (2) ◽  
pp. 272-279
Author(s):  
Leny Fitriah ◽  
Dwi Agustini

Most of the tempe industry have not been equipped with a waste water treatment unit. It is usually a water soaked soybeans and soybean excess water is still discharged directly in the into the environment. Liquid waste industrial of tempeh contain high organic materials. One of the process for wastewater treatment is coagulation with the addition of a positively charged polyelectrolyte in tempeh wastewater as negatively charged. One of plants in Indonesia that can be used as an alternative coagulant is tamarind seeds (Tamarindus indica, L).it can be used for wastewater treatment is more economical. The aims of this experiment is to determine the optimum stirring time, optimum pH of the waste and optimum coagulant dosage for treatment of the tempeh wastewater with coagulant tamarind seed powder. The experiment studied were stirring time, the pH of thetempeh wastewater and coagulant dosage to the percentage decrease in turbidity and COD (Chemical Oxygen Demand). The variables in the experiment were stirring time (10,15, 20, 25 and 30 minutes), the pH of the waste (3; 3.5; 4; 4 and 5) and the dosage of tamarind seed powder (100, 300, 500, 700, and 900 mg / L). COD testing methods is closed reflux method by spectrophotometry and turbidity testing using Turbidimeter. The results showed that the with coagulant tamarind seed powder effectively lowered cod levels and the dryness of tempeh liquid industrial waste. The optimum pH obtained is pH 4, optimum stirring time is 25 minutes and the increase in optimum coagulant dose is 500 mg with a percentage decrease in COD levels and noise by 90.57% and 78.94%.  Key words: liquid waste; sour power; turbidity; COD


Author(s):  
M. Salisu ◽  
Y. L. Gambo ◽  
M. A. Suleiman ◽  
M. K. Yakubu ◽  
B. H. Diya’uddeen ◽  
...  

The secondary effect discovery of synthetic sorbents opened another research direction for many field of studies. However, the sorption parameters of lignocellulosic sorbents are rarely reported most importantly, kenaf shive. This paper centered at the sorption behavior of optimized kenaf shive sorbents using Response Surface Methodology (RSM) via surface deposit technique. Five-level Central Composite Design (CCD) experimental matrix was used to analyze the effect of particle sizes (125-1000 µm), stirring time (5-30min) and methyltrimethoxysilane (MTMS) concentration (5-20% v/v) as individual and combined variables process in the developed sorbents. The unmodified shive was compared with the modified, and it reveals a positive shift in the sorption capability. Instrumental analysis such as FTIR (Fourier Transform Infra-Red), DT-TGA (Differential Thermal-Thermogravimetric analysis) and BET (Brunaure-Emmett-Teller) were carried out on the optimized sorbent and the results were in conformity with the sorption results. The sorption behavior deployed fits the pseudo-first-order and Langmuir isotherm with regression coefficient R2=0.9496 and R2=0.9400. The sorption property was found to be spontaneous and exothermic, however, the activation energy studies shows physic-sorption phenomenon with 25.3 kJmol-1 and R2=0.9360.


2021 ◽  
Author(s):  
Demet Dağıdır ◽  
Nil Acaralı

Abstract In this study, experiments were carried out for composite membrane synthesis with m-phenylenediamine (MPD), hydroxyethyl methacrylate (HEMA) and methyl cellulose (MS) by changing process parameters (methyl cellulose ratio, synthesis temperature, stirring time, oven temperature). Taguchi Method, an optimization method for production, was applied to 4 levels 4 parameters. The silica solution was passed through the produced composite membrane, and the filtering property of the membrane for different periods was examined. Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD) were used for characterization of composite membranes. Shore A test was performed to determine the mechanical strength of composite membranes. The amount of silica in membranes obtained because of the silica treatment was determined by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) analysis. As a result, it was seen that the composite membranes produced could be evaluated in the treatment of wastewater containing silica.


2021 ◽  
Vol 18 (24) ◽  
pp. 1412
Author(s):  
Geetha Devi ◽  
Moza Saif Alkalbani ◽  
Anna Jesil ◽  
Joefel Jessica Casino Dumaran ◽  
Sonia Ibarra Buscano

Due to stringent environmental regulations and increased awareness about the environment, effluent treatment has always been a key aspect of research. Textile industry is one of the oldest and technologically advanced complex industrial sectors employing variety of chemicals and large amount of fresh water consumption. These effluents contain substantial amount of organic pollutants and suspended impurities in varying compositions and hence cannot be discharged directly into the environment. The current research work focused on the utilization of Azadirachta Indica powder as a natural adsorbent for the effective removal of organic and suspended pollutants from textile mill effluent. A series of batch experimental studies were performed by varying the pH of textile mill effluent, stirring time, stirring speed and dosage of Azadirachta Indica powder. Chemical Oxygen Demand (COD), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Dissolved Oxygen (DO), conductivity, and turbidity were estimated to study the performance of Azadirachta Indica powder in the removal of pollutants. The characterizations of Azadirachta Indica powder before and after treatment are performed using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The best processing conditions for the effective removal of pollutants from textile mill effluent was obtained at an effluent solution pH 4.0, stirring time 90 min, stirring speed 150 rpm with 1.0 g of Azadirachta Indica powder. The surface morphological structure of Azadirachta Indica powder after batch treatment using scanning electron microscopy indicated that the pollutants are accumulated in the form of clusters on the adsorbent surface. The FTIR spectral analysis indicates the chemical interaction between adsorbent powder and organic pollutants illustrate the characteristic peaks. The study demonstrates that the Azadirachta indica is a promising type of biomass for the effective removal of pollutants from textile mill effluent. HIGHLIGHTS In this research, Azadirachta Indica powder was employed as a natural adsorbent for the effective removal of pollutants from textile mill effluent Batch experimental studies were performed by varying the pH of textile mill effluent, stirring time, stirring speed and dosage of Azadirachta Indica powder and the optimum processing conditions were established The study demonstrates that the Azadirachta indica is a promising type of biomass for the effective removal of pollutants from textile mill effluent GRAPHICAL ABSTRACT


Author(s):  
Uday KN ◽  
Rajamurugan G

Aluminum metal matrix composites are a new class of materials that have gathered more attention from many materialists. Especially, the automotive components like a piston, cylinder block, brake drum, etc., fabricated by different reinforcement, which has exposed better performance over conventional engineering materials. Aluminum composites are generally fabricated by stir casting technique due to simplicity in operation and adaptive to mass or job order production. The paper provides a background for the readers interested in the production of metal matrix composites through stir casting. Based on the literature assessment, the special attentions taken by the researchers to enhance the uniform distribution of particle to avoid agglomeration are discussed. The composite performances mainly depend on the aluminum matrix, particle size, the quantity of reinforcement, preheating temperature of reinforcement, and processing parameters such as stirring speed, stirring time, and wetting agents. The selection of two reinforcements and their suitable parameters for wetting are attaining interest by many researchers and maybe opted as future scope.


Author(s):  
S. Susilowati ◽  
Khanza Lolita Astya ◽  
Ulinnuha Syaiful Bachri

Cooking oil can only be used two or three times, more than that the oil is deemed unsuitable and can harm our health. The reason is, every time the cooking oil is used for frying, an oxidation reaction that is triggered by heat occured and causes the chemical chain bonds in cooking oil become unstable and forms hydroperoxides. The hydroperoxide found in used cooking oil increases the peroxide value. In which, the suitability of cooking oil is based on the peroxide value. In order to reduce the peroxide value in used cooking oil, in this study, Ampo is used as an adsorbent to adsorb the peroxide compound. The procedure used in this study includes a preliminary analysis of the used cooking oil to determine the initial peroxide value. After that, the Ampo adsorbent is activated with 1N Citric Acid to open the pores on the surface of the Ampo. Activated Ampo will then be mixed into 200 ml of used cooking oil with a magnetic stirrer with a stirring speed of 300 rpm and with a temperature of 50oC. The adsorption process was carried out by varying the mass variables of Ampo into 70, 75, 80, 85, and 90 grams, and stirring time of 30, 60, 90, 120, and 150 minutes. After the adsorption process is completed, the cooking oil that has been filtered by the Ampo adsorbent will be analyzed to get the final peroxide value. By knowing the peroxide value before and after the adsorption process, the adsorption isotherm can be calculated. The adsorption process of used cooking oil with Ampo adsorbent proved to reduce the peroxide value, in which stirring times and adsorbent masses were the influential variables in the study. The best result was obtained with 60 minutes stirring time and mass of 75 grams. This condition provided a peroxide value of 0.99 meq/kg, which means that there was a decrease in the peroxide value by 93%. This result is in accordance with the provisions of SNI 3741-2013, with a maximum peroxide value of 10 meq/kg. The maximum adsorption capacity in this study was obtained from the Freundlich equation of 14.6487 mg/gram


2021 ◽  
Vol 7 (11) ◽  
pp. 104282-104305
Author(s):  
Joselito Nardy Ribeiro ◽  
Araceli Verónica Flores Nardy Ribeiro ◽  
Erik Cavalcante Dybwad ◽  
Felipe Tonon Firmino ◽  
Madson de Godoi Pereira ◽  
...  

Black jurema bark powder (BJBP) (Mimosa hostilis Benth) was studied for the removal of textile dyes Methylene Blue (MB) and Indigo Blue (IB) in water. The chemical and physical analysis of BJBP showed a heterogeneous surface with chemical groups capable to interact with MB and IB. The experiments were optimized for use of 1g of BJBP and stirring time of 3 minutes for IB, and 0.5g of BJBP and stirring time of 2 minutes for MB. The maximum adsorptive capacities for IB (115.21 mg/g) and MB (3.50 mg/g), obtained through the Langmuir Mathematical Model, were favorable for the use of BJBP as an adsorbent in water containing both dyes. The results obtained in this work suggest BJBP as a new alternative for the removal of IB and MB in aqueous medium. Besides, this work stimulates new studies to evaluate the BJBP adsorption capacity for other chemical pollutants.


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