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sulfuricacid, etc ; electrochemistry; hydrogen; hydrolysis; manganese; manganese monoxide; voltammetry; Show all 7 Subjects
Abstract:
... The effect of Fe³⁺ ions on the ocean manganese nodule reductive leaching in imitated sulphuric acid solutions was investigated. This work is presented in two courses, including the influence of Fe³⁺ ions on valuable metal extraction and the electrochemical reductive dissolution of manganese nodules. The results show that the beneficial effects of Fe³⁺ ion can be interpreted based on two aspects: t ...
sulfuricacid, etc ; ammonia; hydrogen; ozonolysis; quantum mechanics; reaction mechanisms; Show all 6 Subjects
Abstract:
... Criegee intermediates (CIs), formed in the ozonolysis process of unsaturated hydrocarbons, play an important role in the formation of OH radicals, sulfuric acid, and aerosols. In this study, quantum chemical calculations were carried out to investigate the mechanism for the reaction of Criegee intermediates [involving CH₂OO, CH₃CHOO and (CH₃)₂COO] with OH radicals at the level of CCSD(T)/jun-cc-pV ...
sulfuricacid, etc ; anodes; arsenic; electrolytes; leachates; purification methods; tin; volatilization; Show all 8 Subjects
Abstract:
... As the different properties of conventional copper anode slime and scrap copper anode slime (SCAS), the disposal of arsenic before the extraction process is very important. There was simultaneous leaching of As and Sn when the hydrometallurgical process or the sulfation roasting-leaching was applied to treat arsenic in the SCAS. It was difficult to achieve the effective separation of arsenic and t ...
sulfuricacid, etc ; adsorption; atomic force microscopy; copper; electrochemistry; sorption isotherms; Show all 6 Subjects
Abstract:
... 2,5-dihydroxy-1,4-dithiane (DDD) and 2,5-dimethy- [1.4] dithiane-2,5-diol (DTDD) two food flavors as environmentally-friendly inhibitors for Cu in 0.5 mol/L H₂SO₄ media were researched via theoretical calculation and experimental ways. Electrochemical measurement data showed that DDD and DTDD can exhibit high level anti-corrosion feature. The anti-corrosion efficiency of DDD and DTDD were as high ...
sulfuricacid, etc ; bioleaching; circular economy; iron; pH; sulfur; waste incineration; Show all 7 Subjects
Abstract:
... The biological leaching of metals from different waste streams by bacteria is intensively investigated to address metal recycling and circular economy goals. However, usually external addition of sulfuric acid is required to maintain the low pH optimum of the bacteria to ensure efficient leaching. Extremely acidophilic Acidithiobacillus spp. producing sulfuric acid and ferric iron have been invest ...
sulfuricacid, etc ; hydrolysis; lead; oxalic acid; reducing agents; sediments; tin; Show all 7 Subjects
Abstract:
... Zinc-leaching residue (ZLR) with 0.46% Sn and 54% Pb brings potential threats to environment but is worthy to recover valuable metals. Reduction of Sn(IV) to Sn(II) is critical for tin extraction. In this work, selective extraction and recovery of tin from ZLR via oxalic acid/sulfuric acid leaching and hydrolytic precipitation was proposed. Various reductants were attempted, and the oxalic acid sh ...
sulfuricacid, etc ; biomass; corn cobs; hemicellulose; lignin; pyrolysis; sodium hydroxide; wastes; Show all 8 Subjects
Abstract:
... Influence of organic biphasic pretreatment on levoglucosan (LG) yield from biomass pyrolysis was investigated with dilute sulfuric acid and dilute sodium hydroxide pretreatment as comparison, simultaneously, the mechanism was explored in depth. It was found that with monophasic (water) conditions, dilute sulfuric acid and dilute sodium hydroxide pretreatment, the yield of LG was all increase large ...
sulfuricacid, etc ; activation energy; environmental impact; sludge; sulfur; volatilization; waste management; Show all 7 Subjects
Abstract:
... The disposal and management of sulfur-rich sludges (SRS) are challenging issues for the industries due to their adverse environmental impact. The present study reports the detailed characterizations and assessment of the thermo-kinetics of sludge generated from the sulfuric acid plant. In addition, the sulfur was retrieved with the help of the evaporation–condensation method. In the active devital ...
sulfuricacid, etc ; aluminum; bauxite; iron; scandium; slags; sodium; sulfates; sulfur; temperature; Show all 10 Subjects
Abstract:
... A closed-loop valorization process, combining carbothermic smelting and acid baking – water leaching was developed to recover scandium, aluminum, and iron from bauxite residue, a major side product of aluminum production. This process employs carbothermic smelting to recover 99% of the iron in the starting residue as crude metallic iron, which can be separated from slag that contains aluminum and ...
sulfuricacid, etc ; acid sulfate soils; probability; sulfates; support vector machines; Finland; Show all 6 Subjects
Abstract:
... Acid sulfate soils are one of the most environmentally harmful soils existing in nature. This is because they produce sulfuric acid and release metals, which may cause several ecological damages. In Finland, the occurrence of this type of soil in the coastal areas constitutes one of the major environmental problems of the country. To address this problem, it is essential to precisely locate acid s ...
sulfuricacid, etc ; biodiesel; catalysts; esterification; lipids; methanol; sludge; solvents; temperature; wastewater; Show all 10 Subjects
Abstract:
... To realize higher yields of mono-alkyl esters (Biodiesel) without sacrificing the environment and food sources; various researchers have considered utilizing different waste materials. In this work lipid extraction and their conversion into esters from wastewater sludge was investigated using a mixture of polar and non-polar solvents, methanol and homogeneous sulfuric acid catalyst. The effect of ...
sulfuricacid, etc ; absorption; dextran; glucose; phenol; quantitative analysis; temperature; water solubility; Show all 8 Subjects
Abstract:
... With structural diversity of water-soluble polysaccharides, their precise quantitative analysis by phenol‑sulfuric acid method becomes more difficult and challenging. In this study, the quantification analysis of dextran and glucose in phenol sulfuric acid method was compared in this paper. When the concentration is below 90 μg/mL, the quantification of glucose is close to theoretical value, howev ...
sulfuricacid, etc ; ambient temperature; biomass; catalytic activity; esterification; process design; vapors; wood; Show all 8 Subjects
Abstract:
... Solid acid carbon catalysts were synthesized from wood activated carbon in granular (GAC) and monolith (ACM) forms using incipient wetness and plasma or hydrothermal methods at sulfonation agent:carbon ratios of 0.62:1 to 1.75:1 [v/w, mL/g], significantly lower than a commonly used ratio of 10:1 (6–16× lower). Yet, esterification rates and yields were comparable to those of catalysts generated wit ...
sulfuricacid, etc ; Acidithiobacillus thiooxidans; bioleaching; electronic wastes; pH; pulp; risk; waste composition; Show all 8 Subjects
Abstract:
... The main objective of this work is to introduce a new green recycling process for recovering valuable metals from electronic waste. One of the fastest-growing electronic waste streams is end-of-life light emitting diodes (LEDs). Due to environmental risk and a worldwide shortage of metals, recycling and recovering their valuable metal is an urgent task. In this study, an innovative bio-hydrometall ...
sulfuricacid, etc ; adsorption; biochar; carbonization; density functional theory; enrofloxacin; garlic; pyrolysis; thermodynamics; Show all 9 Subjects
Abstract:
... This study put forward a one-step carbonization method by concentrated sulfuric acid to prepare garlic peel derived biochar, and the synthetic conditions were optimized by L₁₆(4⁵) orthogonal experiments. Notably, in order to study the differences between the proposed synthetic method and the conventional pyrolysis method, the concentrated sulfuric acid carbonized garlic peels biochar (CSGPB) was c ...
sulfuricacid, etc ; crosslinking; glutaraldehyde; nanofiltration; pH; permeability; phosphoric acid; phosphorus; sodium; styrene; sulfonates; Show all 11 Subjects
Abstract:
... The conventional wet process of extracting phosphorus using concentrated sulfuric acid produces crude phosphoric acid rich in multiple ions. High-end applications require purification of the crude phosphoric acid by removing the ions at an affordable cost. At low pH, phosphoric acid mainly exists as a neutral molecule. Nanofiltration (NF) membranes have been proposed to remove multivalent ions whi ...
sulfuricacid, etc ; acid treatment; biomass; depolymerization; lignin; lignocellulose; molecular weight; rice; silica; wastes; Show all 10 Subjects
Abstract:
... Investigations on the compositional analysis of lignocellulosic materials and their properties upon recovery are essential to be studied in order to examine the effects of recovery method, their dependency on the substrate, etc. In this work, three rice husks (RHs) samples were subjected for alpha-, beta- and gamma-cellulose, pentosan, and silica quantifications. Correlations between the source of ...
sulfuricacid, etc ; aromatization; carbon; carbonization; coal; hydrochars; nitrogen; sewage sludge; sulfur; synergism; temperature; Show all 11 Subjects
Abstract:
... In this study, co-hydrothermal carbonization (co-HTC) of sewage sludge(SS) and coal slime(CS) was studied for preparation of N, S doped hydrochar. The effect of blending ratios and temperature was also investigated. The results showed that there existed a synergistic effect during co-HTC, especially at the ratio of 7:3. Compared with the calculated values, the experimental values of the fixed carb ...
sulfuricacid, etc ; cobalt; energy; hot water treatment; hydrogen production; nitrogen; prices; pyrolysis; zinc; Show all 9 Subjects
Abstract:
... Due to the high price and rareness of precious metal electrocatalysts, the preparation of cheap, high-efficiency nonprecious metal electrocatalysts is urgently needed. In this paper, a Co-metal-organic framework (MOF) has been synthesized by the hydrothermal method. In view of the poor electrocatalytic performance of pristine Co-MOF, we used it as a template and obtained the Co-MOF-800 electrocata ...
Luis F.O. Silva; Marcos L.S. Oliveira; Tito J. Crissien; M. Santosh; Juan Bolivar; Longyi Shao; Guilherme L. Dotto; Juciano Gasparotto; Michael Schindler
sulfuricacid, etc ; environmental impact; phosphogypsum; phosphoric acid; phosphorus fertilizers; raw materials; rock phosphate; toxicity; Show all 8 Subjects
Abstract:
... Many industrial by-products have been disposed along coastlines, generating profound marine changes. Phosphogypsum (PG) is a solid by-product generated in the production of phosphoric acid (PA) using conventional synthesis methods. The raw material, about 50 times more radioactive as compared to unperturbed soils, is dissolved in diluted sulfuric acid (70%) forming PG and PA. The majority of both, ...