Vacuum Distillation Process Research Articles

One step to direct extracted gold and silver from industrial Cu-Ag-Sb-Au alloy by a convenient bimetallic electrolytic separation process

Cu-Ag-Sb-Au alloy produced from lead anode slime reduction smelting through twice vacuum distillation is a high value-added precious metal resource. Currently, using pyrometallurgical process, the antimony and copper elements can be removed respectively by multistage oxidation refining, and then the precious metals are recycled by electrolytic refining. This process has a number of shortcomings such as high energy consumption, high pollution and low direct yield. In this study, a highly efficient new process for extracting precious metals from Cu-Ag-Sb-Au alloy by one-step bimetallic potential-controlled electrolysis is proposed. The electrolytic process of Cu-Ag-Sb alloy is studied by linear scanning voltammetry and electrochemical impedance spectroscopy, and the experimental verification is carried out under the guidance of Cu-Ag-Sb alloy experiments. The results show that gold and silver are enriched in the electrolytic anode slime, while copper and antimony are reduced and deposited on the cathode, which realizes the efficient separation of gold and silver from copper and antimony. The direct yield of precious metals and the anode treatment rate are as high as 99.97 % and 16.02 kg/day·A·m2, respectively, but the energy consumption is 453.90 kW·h/t only. This process strongly supports the treatment of Cu-Ag-Sb-Au alloy with low cost and high efficiency. At the same time, in combination with the vacuum distillation process, the oxidation refining is successfully removed from the lead and copper smelting system, thereby achieving efficient recovery and effective reuse of the precious metals.

New approach to predict impurity concentration in high-purity antimony metal prepared by vacuum distillation

Previous studies have shown that there is a significant difference in impurity concentration in the distillate, resulting in an unclear average impurity concentration in the distilled product. To address this issue, a variation model of impurity average concentration in the distillate was developed based on the mass conservation of the solute during the vacuum distillation process. Five continuous distillation experiments of crude antimony (Sb) metal were carried out to obtain the variation regularity of impurity average concentration in the distillate, and two verification experiments of vacuum distillation were conducted to verify the model. The research results showed that, the concentration of As impurity in residue decreases exponentially as the distillation proceeds, whereas the concentration of Bi impurity increases exponentially; there are the increasing and decreasing concentration gradients of As and Bi impurities in the distillate along with the decreasing condensing temperature, respectively; the average concentrations of As and Bi impurities in the distillate present the linearly decreasing and exponentially increasing tendency, respectively; the calculated values of As and Bi impurities average concentrations in the distillate are in good agreement with the values of two verification experiments, confirming the efficacy of the model.

A review of preparing high-purity metals by vacuum distillation

With the development of science and technology, the high-tech industry has increasingly higher requirements for the purity of metals. However, the presence of trace impurities can have a bad effect on the properties of metals. Vacuum distillation process is widely used to prepare high-purity metals because of its advantages of high metal recovery, good environmental protection and simple equipment. In this paper, the overall progress in the preparation of high-purity metals around the principle and process research of vacuum distillation is systematically summarized. Principles of vacuum distillation, variant design of vacuum distillation, parameter optimization and simulation are covered. Based on the current status of the preparation of high-purity metals by this technology, it is pointed out that mechanistic studies and simulations are indispensable in scientific research. This research has certain reference significance for improving production efficiency, saving production cost and improving metal purity.

A noval salt effect coupled vacuum distillation process for high efficient ultra-azeotropic reuse of spent HCl

The escalating challenge of recycling and treating spent hydrochloric acid (HCl) in various industries, driven by stringent environmental regulations, necessitates urgent solutions for the reuse of spent HCl in industrial processes. However, the concentration and reuse of spent HCl have been impeded by azeotropism. In this study, an innovative salt effect coupled vacuum distillation process was introduced to enable the rapid and convenient recovery of HCl. Salts and vacuum environment both can be found to break the azeotropism effectively, augment the disparity in the dissociation abilities of HCl and H2O in clusters, and enhance the evaporation rate. Specifically, MgCl2 and CaCl2 salt systems were selected, achieving recovered HCl concentrations of 9.66 and 9.85 mol/L, with corresponding recovery rates of 86.45 % and 80.65 %, respectively. For the reuse of spent HCl from chlorinated distillation for extracting germanium (Ge), the presence of As(V) poses a risk to Ge recovery and potential contamination of the Ge product. Excellent resistance to As(Ⅴ) mobilization (<2%) was obtained in the CaCl2 system. To comprehensively understand the salt’s role in breaking azeotropism, molecular simulations were employed. The Mg2+/Ca2+ ions were observed to bind with H2O molecules in the solution, weakening the force between H2O and HCl, decreasing the dissociation energy of HCl molecules by 35 times (from 102.82 to 2.94 kJ/mol), and increasing the dissociation energy of H2O molecules from 52.5 to 61.5 kJ/mol. The proposed process integrates high HCl recovery with an ultra-azeotropic concentrating effect, offering a novel approach for reusing spent HCl in industrial applications.

Anti-Inflammatory Activity of Vacuum Distillate from Panax ginseng Root on LPS-Induced RAW264.7 Cells.

Panax ginseng has been widely applied as an important herb in traditional medicine to treat numerous human disorders. However, the inflammatory regulation effect of P. ginseng distillate (GSD) has not yet been fully assessed. To determine whether GSD can ameliorate inflammatory processes, a GSD was prepared using the vacuum distillation process for the first time, and the regulation effect on lipopolysaccharide-induced macrophages was assessed. The results showed that GSD effectively inhibited nitric oxide (NO) formation and activation of inducible nitric oxide synthase (iNOS) mRNA in murine macrophage cell, but not cyclooxygenase-2 production. The mRNA expression pattern of tumor necrosis factor alpha and IL-6 were also reduced by GSD. Furthermore, we confirmed that GSD exerted its anti-inflammatory effects by downregulating c-Jun NH2-terminal kinase (JNK) phosphorylation, the extracellular signal-regulated kinase phosphorylation, and signaling pathway of nuclear factor kappa B (NF-κB). Our findings revealed that the inflammatory regulation activity of GSD could be induced by iNOS and NO formation inhibition mediated by regulation of nuclear factor kappa B and p38/JNK MAPK pathways.

Investigation of arsenic removal from industrial yellow phosphorus through vacuum distillation: Thermodynamic and ab initio molecular dynamics

This study employs theories involving saturated vapor pressure, separation coefficient, and vapor–liquid equilibrium composition to investigate the feasibility of using vacuum distillation to separate phosphorus and arsenic. Ab initio molecular dynamics simulations are used to analyze the structure, stability, and dynamics of AsnPm (m + n ≤ 8) clusters, assessing their impact on removing arsenic during the vacuum distillation of industrial yellow phosphorus. Theoretical calculations indicate that vacuum distillation is an effective method for removing arsenic from industrial yellow phosphorus. Throughout the vacuum distillation process, clusters like AsP, AsP2, AsP3, and others are prone to diffuse into the gas phase and remain stable, affecting the efficiency of arsenic removal. The collected red phosphorus shows a reduced arsenic content from 136 mg/kg to 1.09 mg/kg, confirming the feasibility of using vacuum distillation to eliminate arsenic from industrial yellow phosphorus and convert it into stable red phosphorus.

Development of Essential Oil Potential as Raw Material for Making Mi Amore Perfume in Jeulekat Village, Blang Mangat District

Along with the development of modern industries such as the perfume, cosmetic, food, aromatherapy and pharmaceutical industries, the world's need for essential oils is increasing every year. Several parameters developed in this article include the effect of pressure (1, 2, 4, 6, 8) mmHg and time (20, 40, 60) minutes until final boiling point on the volume of oil produced and geraniol concentration. The analysis carried out was GCMS analysis and bacterial activity in the application of perfume products. From the research results it was found that at 1 atm pressure the geraniol concentration increased by 50% to 80.11%. Apart from these compounds, other compounds were also obtained such as citronellol, rhodinol and cheprol. at this pressure also produced the highest product volume of 21.2 ml. The application of the product resulting from the vacuum distillation process in the form of an anti-bacterial perfume at an incubation time of 48 hours has the strongest anti-bacterial activity with a diameter of 10.13 mm against Staphylococcus aureus bacteria.

IMPROVEMENT OF FUEL OIL VACUUM RECTIFICATION PROCESS

Primary oil distillation units form the basis of all oil refineries; the quality and yield of the resulting fuel components, as well as raw materials for secondary and other oil refining processes, depend on their operation. Many Atmospheric Vacuum Tubing (AVT) plants are characterized by low recovery of heavy vacuum gas oil. Insufficient selection of heavy vacuum gas oil production leads to a high yield of vacuum residue - tar, which reduces the volume of oil refining in general.The article analyzes ways to improve the process of vacuum distillation of fuel oil at CDU/AVT primary oil distillation units, and searches for ways to increase the efficiency of already built CDU/AVT plants by increasing the selection of heavy vacuum gas oil. Options for technical re-equipment are presented to improve the technical and economic efficiency of atmospheric-vacuum tubing plants with the maximum use of the best achievements in this area and the maximum possible selection of heavy vacuum gas oil at existing primary oil distillation units. The schemes of intensification during vacuum distillation by the method of fractionation of hydrocarbon raw materials by exposing it to electromagnetic oscillations, by the method of gas oil cryolysis. Besides, the schemes of fuel oil distillation according to a two-column scheme and the rectification of half-tar in an additional vacuum column are considered. The main features in the technological design of the process, as well as the features of installation operation, are noted. The proposed schemes make it possible to obtain high-quality feedstock for catalytic cracking and hydrocracking with a high recovery of vacuum gas oil.

Study on continuous crystallization and purification of bismuth from Pb-Bi alloy

The crude bismuth obtained from the smelting of bismuth concentrate and bismuth-containing by-products contains 5%∼20% lead, which needs to be removed during the refining of crude bismuth. Due to the similar physical and chemical properties and metallurgical behavior of lead and bismuth, it is not easy to perform the separation by conventional methods. Although the conventional process of chlorinating crude bismuth to remove lead can meet the requirements of the refining process, the amount of chlorinated slag produced is large, and the safety of chlorine gas is difficult to control, making it difficult to achieve clean production. In this paper, single-factor experiments and semi-industrial experiments for the separation and purification of bismuth from Pb-Bi alloy were carried out by the continuous crystallization method, and the results showed that the bismuth content of Pb-Bi alloy increased from 90.24% to 98.98%, the direct yield of bismuth was 87.37%, the metal recovery rate was 99.84%, and the slag production rate was 0.62%. In comparison with existing processes and studies, the method is low-cost, clean, and efficient, has a wide treatment range, can be operated continuously, and can be easily industrialized and promoted. Theoretically, this method, combined with the process of vacuum distillation to treat Pb-Bi binary alloys with greater than 55.5% bismuth content, results in a 99.99% bismuth product.

Preparation of wood plastic composite from flax fibers and post consumed polystyrene foam based on environmental and economical scales

Due to the high cost of transportation and the lack of established, affordable recycling routes, the rate of recycling of previously used polystyrene foam is extremely low. In this study, a novel treatment technique will be used to examine the feasibility of using waste polystyrene foam as a raw material to produce wood plastic composite (WPC). Where, the recycled polystyrene (rPS) foam waste was first dissolved in methylene chloride and compounded directly with flax fiber (FF) and additives forming a composite paste. The composite paste was then passes through vacuum distillation process for drying the composite paste and also for solvent recovery to reuse it in a further process. The dried composite was processed through thermal mixer extruding and compression molding processes to form the final WPC. The study discovered that WPC with 60 parts per hundred parts of resins (phr) of FF and 2 phr of dioctylphthalate (DOP) may be used to create rPS/FF composite with a proper tensile strength of 19.3 MPa, flexural strength of 78 MPa and compressive strength of 173 MPa compared to another WPS,s based on PVC, HDPE and PP . In addition of that the resulted composite possesses a great potential in manufacturing WPC with environmental and economical demanding application as wooden furniture and as a wooden panels for cladding the exterior building faces.

Separation of lead sulfide from galena concentrate via two-step vacuum distillation

Lead sulfide is a semiconductor with many important applications. In this study, an efficient two-step vacuum distillation process was proposed to separate and purify lead sulfide from galena concentrate. First, impurities such as antimony trisulfide and arsenic sulfide in galena concentrate were removed through vacuum distillation at 900 K, which showed that 98.32% of antimony and 92.4% of arsenic were eliminated. Secondly, lead sulfide in galena concentrate was separated through another vacuum distillation. In this section, the variables considered in the experimental study are vacuum distillation temperature, pressure and time. Experimental data showed that under certain conditions, up to 99% of the lead sulfide was recovered, leaving less than 1% in the residue. In addition, we have studied the effects of vacuum distillation temperature and time on the purity of lead sulfide products. It has been shown that the purity of lead sulfide can be as high as 99% under optimal conditions. This work presents a promising technique for separating lead sulfide from galena concentrate.

Process simulation and distillation unit design vacuum fractionation of rhodinol from citronella oil

The application of biodiesel will increase in accordance with the government’s mandatory program for saving fossil fuels. The challenging would come from particulate levels and water content. One of the efforts to fix the issues is by adding rhodinol from citronella oil as an additive. This research was conducted to design a vacuum distillation process which has 500L of capacity and determine the design of the fractionation distillation unit. Simulation was carried out using the Aspen HYSYS software. The result of the simulation is expected to provide an overview of the fractionation process that would comply with the standard after some data validation. The simulation was applied by vacuum pressure in 4-5 mbar and variation of reflux ratios 1,2, and 3. The best simulation obtained was reflux ratio 2 at 47.80% geraniol and 61.34% citronellol concentrations. The simulation also obtained the following results are maximum and minimum pipe diameter of 0.04 m 0.02 m, the maximum and minimum thickness of 3.7 mm 2.8 m, column height of 10.5 m, column diameter of 0.2412 m, and thickness of 3 mm, condenser length and diameter of 1.11 m and 0.2032 m, reboiler length, and diameter of 1.5 m and 0.6515 m.

Degree of Impurity and Carbon Contents in the Grain Size of Mg-Al Magnesium Alloys.

In this study, the tendency of having different grain structures depending on the impurity levels in AZ91 alloys was investigated. Two types of AZ91 alloys were analyzed: commercial-purity AZ91 and high-purity AZ91. The average grain size of the commercial-purity AZ91 alloy and high-purity AZ91 is 320 µm and 90 µm, respectively. Thermal analysis revealed negligible undercooling in the high-purity AZ91 alloy, while undercooling of 1.3 °C was observed in the commercial-purity AZ91 alloy. A CS analyzer was employed to precisely analyze the carbon composition of both alloys. The carbon content of the high-purity AZ91 alloy was found to be 197 ppm, while the commercial-purity AZ91 alloy contained 104 ppm, indicating a difference of approximately 2 times. The higher carbon content in the high-purity AZ91 alloy is believed to be due to the use of high-purity pure Mg in its production (the carbon content of high-purity pure Mg is 251 ppm). To simulate the vacuum distillation process commonly used in the production of high-purity Mg ingots, experiments were conducted to investigate the reaction of carbon with oxygen to produce CO and CO2. XPS analysis and simulation results for activities confirmed the formation of CO and CO2 during the vacuum distillation process. It could be speculated that the carbon sources in the high-purity Mg ingot provide Al-C particles, which act as nucleants for Mg grains in the high-purity AZ91 alloy. Thus, it can be considered the main reason that high-purity AZ91 alloys have a finer grain structure than that of commercial-purity AZ91 alloys.

Plastic-made diesel (PMD) from pyrolysis via vacuum distillation process- A waste recycling fuel to diesel engine performance and emissions improvement

Plastic applications are remarkably increasing nowadays; thus disposal of waste plastic and its negative environmental impact is a great challenge. Turning waste plastic into useful diesel as an alternative to petroleum fuel in the diesel engine is very attractive for communities in terms of waste plastic recovery and reduction in dependency on fossil fuel. This study conducted experiments to evaluate the engine performance and emissions using plastic-made diesel (PMD) which was produced from pyrolytic crude oil of a mixture of high-density polyethylene (HDPE), polypropylene (PP) and polystyrene (PS) with equal proportion using a vacuum distillation process. The pyrochemical properties of PMD were first evaluated after distillation and tabulated. Then, three different ratios (5%, 10% and 20%) of PMD with ultra-low sulfur diesel (ULSD) were used as a diesel engine fuel to investigate engine performance and emission characteristics at variable speeds and loading operations. Results showed that the brake power (BP), torque and brake thermal efficiency of the engine with PMD20 were 2.9%–3.84%, 3.01%–3.21% and 3.9%–4.74% higher than those with ULSD at all tested conditions. The brake-specific fuel consumption (BSFC) of the engine using PMD20 decreased by about 3.77% compared to the engine using ULSD, thereby indicating less fuel usage at various load circumstances than the ULSD. Furthermore, CO emissions from PMD20 were 14.51% lesser than ULSD, and about 7.8% and 4.22% lesser than from PMD5 and PMD10 at all loading operations, respectively. The HC emissions of PMD20 were 15.1%–18.7% lower than that of the ULSD. The NOx emissions decreased by 2.06%, 3.01% and 3.95% on PMD blends PMD5, PMD10 and PMD20 compared to ULSD. These analyses demonstrate that PMD is a potential alternative fuel for engines and provides a useful means to recover the waste plastics.

THE EFFECTS OF DISTILLATION TEMPERATURE AND PLASTIC LOADING ON THE IMPROVEMENT OF WASTE-DERIVED BIO-OIL PROPERTIES

Since plastic and food waste are both types of non-lignocellulosic biomass, these must be handled and managed correctly to avoid pollution problems and damage to the environment. Bio-oil, made from recycled materials, including plastic and food waste, is one focus of these attempts. The co-pyrolysis method is being investigated in this study as a technique of recycling plastic waste and food waste to produce biofuels with reduced environmental impact. In terms of energy efficiency, bio-oil is unequal to other fuels like coal or natural gas because of its high acidity, high oxygen content, and low thermal stability. Therefore, a vacuum distillation process is required to improve bio-oil quality by adjusting the distillation temperature from 300 to 350 OC and the percentage of plastic waste used from 30 to 50%. The bio-oil was analyzed using a Gas Chromatography-Mass Spectrometer (GC-MS). The general compound showed that acids (60%) and alcohols (20%) were the most prevalent chemical compounds, followed by phenol (4%), aldehyde (14%), aliphatic (5%), Furan (14%), and ketones (11%) at maximum temperature (350 oC) for 30-50% plastic waste. Meanwhile, the final product is affected by temperature and plastic waste (PET) ratio factors. At 350 °C and a plastic waste addition of 50%, the highest bio-oil yield is 45%.

Production of solid fuel in the vacuum distillation of bio-oil

The production of novel solid fuel (bio-coal) with its physicochemical quality similar to coal was investigated in the vacuum distillation of pyrolysis bio-oil from agricultural waste like straw as the raw material. The effect of distillation temperature and pressure on the yield of bio-coal and distillates during the vacuum distillation process was focused, as well as the elemental analysis, microscopic morphology, calorific value and combustion performance of bio-coal samples. The yield of bio-coal was up to 45.01 wt% in the vacuum distillation. The carbon content in bio-coal reached 70.93% with its fuel ratio of 1.14, and calorific value of 29.05 MJ/kg. Thermogravimetric analysis revealed that the initiation temperature of the bio-coal obtained at higher distillation temperature and lower distillation pressure was significantly lower, and they presented better overall combustion effects with higher combustibility index and complete combustion characteristics index. Taking the available waste straw each year as the raw material, the total output of bio-coal in the vacuum distillation process is comparable to 330 million tons of standard coal, accounting for 11.67% of China's annual coal consumption. This study proposes a novel way for optimizing China's present energy structure, reducing agricultural waste pollution, and finally achieving energy sustainability.

The Impact of Redistillation Temperature using Rotary Vacuum Evaporator on the Quality of Aceh Patchouli Oil

Patchouli oil is one of the most important essential oil commodities in Indonesia. At present the Special Region of Aceh, especially Aceh Jaya, Gayo, West Aceh, South and Southeast Aceh, is still the largest patchouli plant centre in Indonesia. So that many Aceh patchouli artisans sell their patchouli products to industries. However, there are several obstacles in this industry that cause the prices of patchouli oil products to become unstable and reduce the competitiveness of the national patchouli oil industry. One innovation that can be done to improve competitiveness is to make isolate products from patchouli oil which has a high selling value, namely patchouli alcohol (PA). PA isolation from patchouli oil can be done by a combination of vacuum distillation. In this study begins with a vacuum distillation process of patchouli oil. Patchouli oil used is taken from sources refined by Aceh farmers. Variable is refining temperature. The distillation temperature is set at 120, 125, 130, 135, 145, 155, 165, and 175 oC. Patchouli oil was analysed with patchouli alcohol, specific gravity, refractive index and acid number. The results showed that the value of patchouli oil refractive index increased from 1.507 to 1.512; density increased to 1.005 g/ml; acid number increased slightly from 5.5 to 5.8; and patchouli alcohol increased from 34% to 65.9%.

Characterization and Physical Propertiesof Terpene Compound in Citronella Essential oil as Sources of Antibacterial Perfume

ABSTRACT Along with the development of modern industries such as the perfume, cosmetic, food, aromatherapy and pharmaceutical industries, the world's need for essential oils is increasing every year. Several parameters developed in this article include the effect of pressure (1, 2, 4, 6, 8) mmHg and time (20, 40, 60) minutes until final boiling point on the volume of oil produced and geraniol concentration. The analysis carried out was GCMS analysis and bacterial activity in the application of perfume products. From the research results it was found that at 1 atm pressure the geraniol concentration increased by 50% to 80.11%. Apart from these compounds, other compounds were also obtained such as citronellol, rhodinol and cheprol. at this pressure also produced the highest product volume of 21.2 ml. The application of the product resulting from the vacuum distillation process in the form of an anti-bacterial perfume at an incubation time of 48 hours has the strongest anti-bacterial activity with a diameter of 10.13 mm against Staphylococcus aureus bacteria.Keywords: Characterization, Citronella Oil, Vacuum Distillation, Perfume, Terpene

Evaporation characteristics of elemental tellurium in the vacuum distillation process based on differential weight method measurement

Vacuum distillation is an indispensable process in the preparation of high purity tellurium. However, kinetic data of tellurium evaporation such as the actual evaporation rate, critical pressure, and evaporation coefficient have not been reported. In this work, the actual volatilization rate of tellurium was measured under different temperature and system pressure conditions. The vacuum volatilization of tellurium was analyzed in detail, which shows that there is a linear relationship between the natural logarithm of tellurium evaporation rate and the reciprocal of temperature, while the system pressure is constant. Additionally, when the distillation temperature is fixed, the tellurium evaporation rate and the system pressure meet the Logistics nonlinear relationship (ωactu = (A1-A2)/[1+(p/p0)a]+A2). Above the melting point of Te, the logarithm of critical pressure is linearly related to the reciprocal of the temperature (lgpcrit = 3.26–937.19/T). The experimental maximum evaporation rate of tellurium is calculated by the method of limiting and the evaporation coefficient α is between 0.4 and 10. The present study provides basic evaporation parameters, describes the behavior of tellurium under vacuum distillation, and offers theoretical guidance for vacuum distillation refining of tellurium.

The Effectiveness of Cooled-Finger and Vacuum Distillation Processes in View of the Removal of Fe, Si and Zn from Aluminium

The increasing demand for ultra-high purity aluminum for technological applications has led to the improvement of refining methods in recent decades. To achieve ultra-purity levels (&gt;5N), the common industrial way is to firstly purify aluminum from 2N8 up to 4N8 via three-layer electrolysis, followed by fractional crystallization (usually zone melting). Since both of these methods are very cost- and time-intensive, this paper aims at providing other alternatives of purification. For this purpose, here, the purification of some selected impurities through cooled-finger fractional crystallization method and vacuum distillation have been the focus of this investigation. Both processes are more environmentally friendly than three-layer electrolysis and require less time than zone melting. In this paper, both methods were explored for the aluminum purification. Moreover, the effect of process parameters on the purification efficiency of iron, zinc, and silicon has been investigated. At the end, the effectiveness of the two processes was compared and advantages and disadvantages were summarized. The results showed that the cooling finger process effectively removed iron and silicon impurities, but the removal efficiency of zinc was low. The vacuum distillation process successfully removes zinc in the first stage of distillation. Iron and silicon removal requires additional distillation stages to achieve lower impurity levels.