Tribological behaviors of DLC films in sulfuric acid and sodium hydroxide solutions

2020 ◽  
Vol 52 (7) ◽  
pp. 396-406
Author(s):  
Wensheng Li ◽  
Dongqing He ◽  
Wei Ren ◽  
Liping Wang ◽  
Lunling Shang ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Sodium Hydroxide ◽  
Tribological Behaviors

The Influence of Heat and Two Stages Precipitation in the Process of Natural Polymer Purification from the Byproduct of Bioethanol Process Base on Empty Palm Fruit Bunch

2015 ◽  
Vol 1123 ◽  
pp. 177-181
Author(s):  
Achmad Hanafi ◽  
Harry Budiman ◽  
Fauzan Aulia
Keyword(s):  
Sulfuric Acid ◽  
Sodium Hydroxide ◽  
Room Temperature ◽  
Black Liquor ◽  
Ash Content ◽  
Natural Polymer ◽  
Palm Fruit ◽  
Second Stage ◽  
Direct Precipitation ◽  
Two Stages

The biopolymer material, lignin, was recovered from the black liquor by acidification of the black liquor using sulfuric acid. Several purification techniques were carried out to produce the high purity of lignin such as gradual precipitation of lignin from black liquor (first stage: precipitation at pH 7, second stage: precipitation at pH 2) and the diluting of crude lignin by sodium hydroxide then followed by re-precipitation at different temperature. Subsequently, the impurities of lignin product resulted from each purification techniques was determined as ash content that analyzed using temperature program furnace; and the content of lignin was investigated using spectrophotometer UV-Vis. The result showed that the content of lignin of material produced from gradual precipitation was approximately 77.6%. It was higher than the content of lignin about 3.4% of material produced from direct precipitation to pH 2. In addition, the elevating of temperature from 40 to 60°C was no considerably affect to the content of lignin in precipitate produced from re-precipitation of crude lignin solution in sodium hydroxide. Nonetheless, the content of lignin of precipitate improved 15% when the temperature of re-precipitation of crude lignin solution in sodium hydroxide was raised from room temperature to 40-60°C.

scholarly journals PEMBUATAN MIKROKRISTALIN SELULOSA ROTAN MANAU (Calamus manan sp.) SERTA KARAKTERISASINYA

2014 ◽  
Vol 4 (02) ◽  
Author(s):  
Steven . ◽  
Mardiyati . ◽  
R. Suratman
Keyword(s):  
Sulfuric Acid ◽  
Natural Resources ◽  
Acid Hydrolysis ◽  
Sodium Hydroxide ◽  
Microcrystalline Cellulose ◽  
High Cellulose

Rattan is one of natural resources of Indonesia which contains 30%-40% cellulose. Its high cellulose contents makes it very potential as a source of microcrystalline cellulose (MCC). In this research, manau rattan was characterized by using the Chesson methods. Microcrystalline cellulose was prepared by using two methods, i.e. alkalization and acid hydrolysis. Alkalization was performed by soaking manau rattan powder into sodium hydroxide 17,5% for 8 hours. Acid hydrolysis was prepared by using sulfuric acid at a concentration of 0.1 M; 0.3 M; and 0.5 M for 4, 6, 8, and 10 hours. The crystallinity of MCC was quantitatively measured by XRD and qualitatively measured by using FTIR. In this research, we have successfully made microcrystalline cellulose from manau rattan. The highest crystallinity MCC of 72.42% was obtained from acid hydrolysis with 0.5 M for 10 hours. The crystallinity of the MCC product increases with concentration and hydrolysis time.Keywords: acid hydrolisis, alkalization, cellulose, manau rattan, MCCABSTRAKRotan merupakan salah satu kekayaan hayati Indonesia yang mengisi sepuluh persen hutan di Indonesia yang memiliki kadar selulosa mencapai 30-40%. Kadar selulosa yang cukup tinggi membuat rotan sangat berpotensi untuk dimanfaatkan sebagai bahan baku mikrokristalin selulosa (MCC). Rotan manau dikarakterisasi menggunakan metode Chesson. Pembuatan mikrokristalin selulosa terdiri atas dua tahap, yaitu alkalisasi dan hidrolisi asam. Tahap alkalisasi dilakukan dengan merendam rotan di dalam larutan NaOH 17,5% selama 8 jam. Tahap hidrolisis asam dilakukan dengan menggunakan asam sulfat pada berbagai konsentrasi, yakni 0,1; 0,3 dan 0,5 M selama 4, 6, 8, dan 10 jam. Kristalinitas dari MCC yang dihasilkan diukur dengan menggunakan XRD. Untuk mengetahui komposisi kimia serta kristalinitas MCC secara kualitatif, telah dilakukan karakterisasi dengan menggunakan FTIR. Pada penelitian ini, telah berhasil dibuat MCC yang bersumber dari rotan manau. Kristalinitas MCC tertinggi dihasilkan dengan perlakuan hidrolisis asam dengan konsentrasi 0,5 M selama 10 jam, yaitu sebesar 72,42%. Seiring dengan peningkatan konsentrasi serta waktu hidrolisis, kristalinitas MCC yang dihasilkan semakin tinggi.Kata kunci: alkalisasi, hidrolisis asam, selulosa, MCC, rotan manau

Latex Battery Separators. Preparation and Properties

1937 ◽  
Vol 10 (2) ◽  
pp. 346-351
Author(s):  
H. W. Greenup ◽  
L. E. Olcott
Keyword(s):  
Sulfuric Acid ◽  
Sodium Hydroxide ◽  
Electrical Resistance ◽  
Sodium Hydroxide Solution ◽  
Storage Battery ◽  
Preliminary Treatment ◽  
Actual Contact ◽  
Dilute Sodium Hydroxide ◽  
Port Orford Cedar ◽  
Highly Porous

Abstract THE commonly used electrical storage battery consists of alternate negative plates of sponge lead and positive plates of lead peroxide immersed in an electrolyte, sulfuric acid; the whole is enclosed in a hard rubber or bituminous composition case. These plates are ordinarily separated from one another by ribbed sheets of wood called “separators.” The separators prevent short circuiting of the plates caused by actual contact of the plates with each other or by “treeing” (formation of lead crystals between the plates). The separators must be thin, in order to make the battery as compact as possible, and yet must be durable. It is necessary that they be highly porous so that their electrical resistance will be low, but the pores must be sufficiently fine so that “treeing” does not take place. Wood separators are ordinarily made of Port Orford cedar. They are usually given a preliminary treatment in warm, dilute sodium hydroxide solution to swell them, thus increasing their porosity, and to remove injurious substances which cause self-discharge and corrosion of the plates. Wood separators have the advantage of being inexpensive and of having fairly low electrical resistance, but they are not so resistant to the action of sulfuric acid and the oxidizing action in the cell as is desirable. They are, in many cases, the first part of the storage battery to fail and must then be replaced if the battery is to give further service.

Carbohydrates in alkaline systems. II. Kinetics of the transformation and degradation reactions of cellobiose, cellobiulose, and 4-O-β-D-glucopyranosyl-D-mannose in 1 M sodium hydroxide at 22 °C

1969 ◽  
Vol 47 (21) ◽  
pp. 3957-3964 ◽  
Author(s):  
Donald J. MacLaurin ◽  
John W. Green
Keyword(s):  
Sulfuric Acid ◽  
Sodium Hydroxide ◽  
Column Chromatography ◽  
Rate Constants ◽  
Reaction Rate ◽  
Reaction System ◽  
Reaction Rate Constants ◽  
Degradation Reactions ◽  
Fructose 2 ◽  
Kinetics Of

Rates of isomerization, epimerization, and degradation reactions were measured for cellobiose (7), cellobiulose (8), and 4-O-β-D-glucopyranosyl-D-mannose (9) at 0.001 M in 1 M NaOH under N2 in the dark at 22 °C. Reaction system resolution was by column chromatography on anion resins in the borate form. Assay for D-glucose (1), D-fructose (2), D-mannose (3), and 7,8, and 9 was by continuous automated colorimetry of column effluent with orcinol–sulfuric acid as reagent. Reaction rate constants (h−1) found: k78 0.078, k79 0.0005, k7,10 0.002, k87 0.022, k89 0.003 k81 0.065, k8,12 0.023, k97 0.002, k98 0.013, k9,11 0.006 where 10,11, and 12 are other products than 1,2,3,7,8, and 9. Details for preparation of 8 and 9 are given.

Effect of Sulfuric Acid /Sodium Hydroxide /Sodium Chloride on Properties of Polyurea

2011 ◽  
Vol 194-196 ◽  
pp. 2330-2333
Author(s):  
Ping Lv ◽  
Xin Mao Li ◽  
Wei Bo Huang
Keyword(s):  
Mechanical Properties ◽  
Sulfuric Acid ◽  
Sodium Chloride ◽  
Sodium Hydroxide ◽  
Decrease Rate ◽  
Hardness Change

This paper mainly studies the glossnesschange、mechanical properties change and hardness change of polyurea coatings during the immersing experiment. The result of the glossness experiment shows that Qtech-116 polyurea sample glossness declining rate were 18.33%, 3.69% and 0.83% after immersed in 5％H2SO4、5％NaOH and 3.5％NaCl for 60d.The mechanical properties results shows that the tensile strengt decrease rate were 16.30%、2.69% and 2.28% after immersed in 5％H2SO4、5％NaOH and 3.5％NaCl for 60d. Qtech-116 polyurea sample hardness showns declined 0.83%、no change and increased 35.81% respectively after immersed in 5％H2SO4、5％NaOH and 3.5％NaCl for 60d.

scholarly journals Durability Studies on Concrete Made Using Pulverized Used Foundry Sand as A Mineral Admixture

2018 ◽  
Vol 7 (3.3) ◽  
pp. 10
Author(s):  
Salim P M ◽  
B S.R.K.Prasad ◽  
Seshadri Sekhar.T
Keyword(s):  
Sulfuric Acid ◽  
Sodium Hydroxide ◽  
Acid Resistance ◽  
Sodium Sulphate ◽  
Mineral Admixture ◽  
Alkali Resistance ◽  
Main Concern ◽  
Test Results ◽  
Foundry Sand ◽  
Ordinary Concrete

Durability of the structures is a main concern now a day due to the various types of deteriorations caused by natural as well as manmade environmental conditions. In this project the durability properties of concrete made with pulverized used foundry sand as a mineral admixture is analyzed. The durability of concrete is mostly depends on the surrounding environment. The chemicals present in air and water are the main causes of deterioration of concrete in its life. So a deep study on the action of deteriorating chemicals on the concrete containing pulverized used foundry sand is initiated. Here M40 concrete is prepared with 0%,5%,10%,15% and 20% addition of pulverized used foundry sand to the cement content. Cubes of size 100mmx100mmx100mm were cast and tested for various parameters like Acid resistance with hydrochloric acid and sulfuric acid, Sulphate attack with sodium sulphate and alkali resistance with sodium hydroxide for. The testing was performed on cubes at 28day, 56 day, 90 day and 180 day stored in respective chemicals dissolved in water at 5% concentration. From the test results it is inferred that the concrete containing pulverized used foundry sand is better in acid resistance than ordinary concrete without pulverized used foundry sand. Further the acid resistance for both hydrochloric and sulfuric acid shows an increase up to 15% addition of pulverized used foundry and after that it is slightly reduced. The samples subjected to sodium sulphate and sodium hydroxide has shown no variation in properties with respect to the water cured specimens.  

Enrichment of Titanium from Panzhihua Mine Tailings

2014 ◽  
Vol 1030-1032 ◽  
pp. 69-72
Author(s):  
Shu Quan Wan ◽  
Cai Long Zhou ◽  
Zhong Xu ◽  
Hong Bo Han
Keyword(s):  
Sulfuric Acid ◽  
Oxalic Acid ◽  
Sodium Hydroxide ◽  
Mine Tailings ◽  
Titanium Content ◽  
Relative Content ◽  
Percentage Content ◽  
Relative Percentage ◽  
Molten Sodium ◽  
Enrichment Process

Relative percentage content of Fe in tailings decreased from 15.92% to 10.71% after treated by using sulfuric acid mixed with oxalic acid at 350K for 60 min. And the relative content of Si decreased from 16.3% to 11.9% after treated by molten sodium hydroxide at 1073K for 30 min. Titanium content increased from 6.315% (original tailings) to 8.512% after removed Fe, and continued to go up to 10.44% after removed Si. The contents of Ca, P and Mn were slightly changed in entire enrichment process by XRF analysis. The phase change of the entire process was studied by XRD, and results indicated that tailings had very complex phases, and after removed Si the phase of tailings partly changed into FeTiO3.

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