sulfamic acid
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Energies ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 24
Author(s):  
Silin Mikhail ◽  
Magadova Lyubov ◽  
Davletshina Lucia ◽  
Poteshkina Kira ◽  
Kotekhova Viktoriia ◽  
...  

Acid treatments are one of the methods for intensifying oil and gas production. Corrosion is a significant factor affecting the performance of oilfield equipment. There are many different methods of preventing corrosion, but corrosion inhibitors are most commonly used in industry. The protective effect of the inhibitor is directly determined by the effective adsorption of surfactants on the metal surface. For an indirect assessment of the adsorption of the inhibitor, a comprehensive research method is proposed based on the determination of the interfacial tension of acid compositions and steel plates’ contact angle of wetting after corrosion tests. It was found that in hydrochloric acid the adsorption of the inhibitor IC-1 reaches a maximum after 6 h, an increase in the acid concentration in the range of 5–15% wt. has a negative effect on the activity of the inhibitor. For sulfamic acid, the maximum adsorption of the IC-2 inhibitor is observed after 24 h, an increase in acid concentration has a positive effect on surfactants.


2021 ◽  
Author(s):  
Abdullah Alharith ◽  
Sulaiman Albassam ◽  
Thamer Al-Zahrani

Abstract Organic and inorganic deposits play a major issue and concern in the wellbore of oil wells. This paper discusses the utilization of a new and novel approach utilizing a thermochemical recipe that shows a successful impact on both organic and inorganic deposits, as an elimination agent, and functions as stimulation fluid to improve the permeability of the near wellbore formation. The new recipe consists of mixing nitrite salt with sulfamic acid in the wellbore at the target zone. The product of this reaction includes heat, acidic salt, and nitrogen gas. The heat of the reaction is enough to liquefy the organic deposits, and the acidic salt will tackle the carbonate scale in the tube and will increase the permeability of the near wellbore area. The nitrogen gas is an inert gas; it will not affect the reaction and will help to flow back the well after the treatment. The experimental work shows an increment in the temperature by 65 °C when mixing the two chemicals. The test was conducted at room conditions and the temperature reached around 90 °C. Adding another 65 °C to the wellbore temperature is enough to melt asphaltene and wax, the acidic salt tackles carbonate scale. As a result, the mixture works on eliminating both the organic and inorganic deposits. The permeability of the limestone sample shows an increment of 65% when treated by the mixture of the reaction recipe. The uniqueness of the new thermochemical recipe is the potential of performing three objectives at the same time; the heat of the reaction removes the organic deposits in the wellbore, the acidic salt tackles carbonate scale, and improves the permeability of the near wellbore zone.


2021 ◽  
Vol 922 (1) ◽  
pp. 012072
Author(s):  
Ratna ◽  
S Aprilia ◽  
N Arahman ◽  
A A Munawar

Abstract The study aimed to characterize cellulose nanocrystalline (NCCs) from banana peduncles using acid hydrolysis. The NCCs isolation process was done by hydrolysis using H2SO4 with concentrations of 1M, 2M, and 3M at a microwave power of 100 Watts within 1 hour of hydrolysis. The product of NCCs was characterized in term of yield, chemical composition (by FTIR), and its crystallinity. The result showed that the highest yield of 88.33% was obtained in acid hydrolysis at the concentration of 1M H2SO4. The results of the FTIR test showed that non-cellulose content had been removed and demonstrated that the molecular structure of cellulose does not change even when treated at different acid concentrations. X-Ray Diffraction analysis showed that crystallinity decreased by increasing the sulfamic acid concentration. The thermogravimetric analysis confirmed the heat resistance analysis and showed that the NCCs is gradually decomposed at a temperature range of 268.3–415.25 ¼C. The colour of cellulose nanocrystalline powder darkens as the sulfuric acid concentration increases.


Foods ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2571
Author(s):  
Aleksandr S. Kazachenko ◽  
Natalya Yu. Vasilieva ◽  
Valentina S. Borovkova ◽  
Olga Yu. Fetisova ◽  
Noureddine Issaoui ◽  
...  

Xanthan is an important polysaccharide with many beneficial properties. Sulfated xanthan derivatives have anticoagulant and antithrombotic activity. This work proposes a new method for the synthesis of xanthan sulfates using sulfamic acid. Various N-substituted ureas have been investigated as process activators. It was found that urea has the greatest activating ability. BBD of xanthan sulfation process with sulfamic acid in 1,4-dioxane has been carried out. It was shown that the optimal conditions for the sulfation of xanthan (13.1 wt% sulfur content) are: the amount of sulfating complex per 1 g of xanthan is 3.5 mmol, temperature 90 °C, duration 2.3 h. Sulfated xanthan with the maximum sulfur content was analyzed by physicochemical methods. Thus, in the FTIR spectrum of xanthan sulfate, in comparison with the initial xanthanum, absorption bands appear at 1247 cm−1, which corresponds to the vibrations of the sulfate group. It was shown by GPC chromatography that the starting xanthan gum has a bimodal molecular weight distribution of particles, including a high molecular weight fraction with Mw > 1000 kDa and an LMW fraction with Mw < 600 kDa. It was found that the Mw of sulfated xanthan gum has a lower value (~612 kDa) in comparison with the original xanthan gum, and a narrower molecular weight distribution and is characterized by lower PD values. It was shown by thermal analysis that the main decomposition of xanthan sulfate, in contrast to the initial xanthan, occurs in two stages. The DTG curve has two pronounced peaks, with maxima at 226 and 286 °C.


Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2778
Author(s):  
Weidong Li ◽  
Yu Xue ◽  
Ming He ◽  
Jiaqiang Yan ◽  
Lucian A. Lucia ◽  
...  

A deep eutectic solvent (DES) composed of sulfamic acid and glycerol allowed for the sustainable preparation of cellulose nanofibrils (CNF) with simultaneous sulfation. The reaction time and the levels of sulfamic acid demonstrated that fibers could be swelled and sulfated simultaneously by a sulfamic acid-glycerol-based DES and swelling also promoted sulfation with a high degree of substitution (0.12). The DES-pretreated fibers were further nanofibrillated by a grinder producing CNF with diameters from 10 nm to 25 nm. The crystallinity ranged from 53–62%, and CNF maintained the original crystal structure. DES pretreatment facilitated cellulose nano-fibrillation and reduced the energy consumption with a maximum reduction of 35%. The films prepared from polyvinyl alcohol (PVA) and CNF showed good UV resistance ability and mechanical properties. This facile and efficient method provided a more sustainable strategy for the swelling, functionalization and nano-fibrillation of cellulose, expanding its application to UV-blocking materials and related fields.


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