Научная статья на тему 'DEPENDENCE OF THE ACTIVITY OF Ti-W-O CATALYSTS IN THE ETHANOL OXIDATION REACTION ON THE ACIDIC PROPERTIES OF THE SURFACE'

DEPENDENCE OF THE ACTIVITY OF Ti-W-O CATALYSTS IN THE ETHANOL OXIDATION REACTION ON THE ACIDIC PROPERTIES OF THE SURFACE Текст научной статьи по специальности «Химические науки»

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Ключевые слова
ethanol oxidation / binary catalysts / tin oxide / vanadium oxide / acetic acid / acetaldehyde

Аннотация научной статьи по химическим наукам, автор научной работы — Məmmədova A.

In this work it was studied the activity of the binary tin-vanadium oxide catalysts in reaction of ethanol oxi-dation to acetic acid. It was found that the main products of ethanol oxidation over tin-vanadium oxide catalysts are acetaldehyde and acetic acid. It is shown that high activity of tin-vanadium oxide catalysts rich in one of the elements due to the formation of solid solutions.

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Текст научной работы на тему «DEPENDENCE OF THE ACTIVITY OF Ti-W-O CATALYSTS IN THE ETHANOL OXIDATION REACTION ON THE ACIDIC PROPERTIES OF THE SURFACE»

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DEPENDENCE OF THE ACTIVITY OF Ti-W-O CATALYSTS IN THE ETHANOL OXIDATION REACTION ON THE ACIDIC PROPERTIES OF THE SURFACE

Mammadova A.

Master Student, Chemical technology faculty, Azerbaijan State Oil and Industry University, Baku, Azerbaijan

Abstract

In this work it was studied the activity of the binary tin-vanadium oxide catalysts in reaction of ethanol oxidation to acetic acid. It was found that the main products of ethanol oxidation over tin-vanadium oxide catalysts are acetaldehyde and acetic acid. It is shown that high activity of tin-vanadium oxide catalysts rich in one of the elements due to the formation of solid solutions.

Keywords: ethanol oxidation, binary catalysts, tin oxide, vanadium oxide, acetic acid, acetaldehyde.

Introduction.

Acetic acid is one of the important chemicals and solvents used in industry [1]. One of the promising methods for producing acetic acid is the direct gasphase oxidation of ethanol on heterogeneous catalysts, proceeding according to the equation.

C2H5OH + O2 ^ CH3COOH + H2O Catalysts based on vanadium oxides, molybdenum oxide and others are highly active in the oxidation of

ethanol to acetic acid [2, 3]. Therefore, this work is devoted to the study of the oxidation reaction of ethanol to acetic acid on mixed tin-vanadium oxide catalysts.

Experimental part.

We prepared binary tin-vanadium oxide catalysts of various compositions by coprecipitation from aqueous solutions of tin tetrachloride and ammonium vana-date. The obtained mixture was successively evaporated and dried at 100-120°C, decomposed at 250°C

until the complete evolution of chlorine vapor and nitrogen oxides, and then calcined at 600°C for 10 hours. Thus, 9 catalysts were synthesized with an atomic ratio of elements from Sn:V=1:9 to Sn:V=9:1. The activity of the synthesized catalysts was studied on a flow-through unit with a tubular reactor in the temperature range 100-500°C. The reactor was loaded with 5 ml of the investigated catalyst with a grain size of 1.0-2.0

mm, and its activity in the reaction of ethanol oxidation to acetic acid was studied.

Results and discussion.

Studies have shown that acetaldehyde, ethylene, acetic acid and carbon dioxide are the products of the oxidation reaction of ethanol over binary tin-vanadium oxide catalysts. The effect of temperature on the activity of the catalyst Sn-V=1-9 in the ethanol conversion

reaction is shown in Figure 1.

Figure 1.

The effect of temperature on the output products of the ethanol oxidation reaction on the catalyst Sn-V = 1-9.

It is seen that the oxidation reaction of ethanol on the studied catalyst begins at 100°C with the formation of 4,2% acetaldehyde and 0,6% of acetic acid. As the reaction temperature increases, the yield of acetalde-hyde in the studied catalyst reaches a maximum value at 200°C and is 50%. As can be seen from Figure 1, the maximum yield of acetic acid is obtained by increasing the temperature. The maximum yield of acetic acid reaches 50.2% at 250°C. The output of ethylene and carbon dioxide increases with increasing reaction temperature over the entire temperature range studied. The highest yields of ethylene and carbon dioxide are observed at 350°C and are 18.9 and 11,7%, respectively. As can be seen from the figure, the conversion of etha-nol increases with increasing reaction temperature and now reaches a maximum of 100% at 200°C and then remains virtually unchanged. Similar results were obtained for other binary tin-vanadium oxide catalysts.

We also examined the dependence of the activity of binary tin-vanadium oxide catalysts on their composition. Figure 2 shows the dependence of the activity of

tin-vanadium oxide catalysts on their composition in the oxidation of ethanol at 200°C. The main reaction products in all catalysts as can be seen are acetaldehyde and acetic acid. The dependence of acetic acid output on the atomic ratio of tin to vanadium is curved with two maxima in Sn-V=3-7 and Sn-V= 8-2. As can be seen from Figure 2, as the atomic ratio of tin to vanadium increases, the yield of ethylene and carbon dioxide reaches a maximum in the sample Sn-V=5-5. In this sample, the lowest output of acetic acid is also observed. The yield of acetaldehyde decreases with increasing atomic ratio of tin to vanadium. It should also be noted that the conversion of ethanol in all samples at 200°C is equal 100%.

A more pronounced dependence of the output of the reaction products on the composition of the catalysts is observed at temperatures above 300°C (Figure 3). As the amount of tin in the catalyst increases, the output of ethylene and carbon dioxide occurs at the maximum value in the sample Sn-V = 5-5.

Figure 2 Dependence of the activity of tin-vanadium oxide catalysts in the oxidation reaction of ethanol on their

composition. T = 200°C

As at low temperatures, in the samples Sn-V=3-7 and Sn-V=8-2, the acetic acid product has a dependence on the atomic ratio of tin and vanadium at two maximum values. The yield of acetic acid in these samples is 50.9%

content in the catalyst, the acetaldehyde output decreases from 36.2% in the Sn-V = 1-9 catalyst to 29.8% in the Sn-V = 9-1 catalyst. As at low temperatures, the conversion of ethanol reaches 100% on the all samples.

Figure 3 The dependence of the activity of tin-vanadium oxide catalysts in the oxidation reaction of ethanol on

their composition. T = 300°C

Based on the obtained results, it can be said that tin or vanadium-rich tin-vanadium oxide catalysts are active in the formation of acetic acid, which is due to the formation of solid solutions in these samples.

Conclusion

1. The main products of ethanol conversion in tin-vanadium oxide catalysts are acetaldehyde and acetic acid;

2. The maximum yield of acetic acid in tin-vanadium oxide catalysts is 55.2%;

3. The high activity of tin-vanadium oxide catalysts, which are rich in one of the elements, is due to the formation of solid solutions.

REFERENCES:

1. Alexandre C.Dimian, Costin Sorin Bildea, Anton A.Kiss. Acetic Acid. Applications in Design and Simulation of Sustainable Chemical Processes, 2019, Pages 483-519

2. Billy B.Bardin, Robert J.Davis. Characterization of copper and vanadium containing heteropolyacid catalysts for oxidative dehydrogenation of propane.

Applied Catalysis A: General, 1999, Volume 185, Issue 2, Pages 283-292

3. Tiina Laitinen, Satu Ojala, Renaud Cousin, Niina Koivikko, Christophe Poupin, Zouhair El Assal, Atte Aho, Riitta L.Keiski. Activity, selectivity, and stability of vanadium catalysts in formaldehyde production from emissions of volatile organic compounds. Journal of Industrial and Engineering Chemistry, 2020, Volume 83, Pages 375-386

LAW AS A MEANS OF ENSURING PUBLIC SAFETY IN THE CONTEXT OF THE INTRODUCTION

OF ARTIFICIAL INTELLIGENCE

Stepanov O.

Doctor of Law, Professor, The Institute of legislation and comparative law under the government of the Russian Federation, Department of criminal, criminal procedural law and judicial

System

Abstract

The article deals with the problem of the relationship between law and security in the context of the introduction of artificial intelligence systems in society.

Keywords: law, security, criminal law, artificial intelligence.

INTRODUCTION

Law and security are one of the most important and complex social phenomena in modern society. And if law, to a large extent, is associated with justice and normative establishments, then safety - with ensuring the functional qualities of both organized systems and a person, associated with preserving their structure and maintaining the necessary (required) mode of life [1].

For the theory and practice of ensuring security in the context of the introduction of artificial intelligence systems into the life society, it is important that the means by which legal requirements are translated into specific behavior at the personal, group and social levels are sufficiently clear. This is especially important in conditions when "digital entities" become the object of legal impact [2]. So, on May 31, 2016, the European Parliament presented a project according to which robots can be assigned the status of «electronic persons» who will be endowed with rights and obligations, and the owners will be required to pay tax contributions for the robots. It is also proposed to create a register of intelligent autonomous robots, each of which will be assigned funds to cover its legal obligations. Along with this, in January 2017, a report was prepared in one of the EU committees, which provides for the granting of legal status to robots. MEPs passed a resolution urging Brussels to take action on robotics as the role of robots in everyday life becomes more and more important. In April 2018, the European Commission published Artificial Intelligence for Europe, which outlined the EU's approach to harnessing the power of AI and meeting the challenges it faces.

The Declaration of the Committee of Ministers of the Council of Europe on risks in decision-making with a computer or artificial intelligence in the field of the social protection system, adopted on March 17, 2021, raises the issue of human rights violations when using

artificial intelligence in decision-making processes, and calls for ensure that when using AI algorithms, fairness and ethical requirements for all people are met - "technologies may include a "code" used in decision-making, which, depending on its characteristics or teaching methods, may mistakenly deprive people of rights and benefits, thus by the most encroaching on their social rights" [3].

In the Declaration, the Committee of Ministers draws special attention of the EU member states to the following problems:

- possible risks to human rights, including social rights, which may arise as a result of government decision-making using a computer or artificial intelligence;

- the need to ensure the development and implementation of decision-making systems using computers or artificial intelligence in accordance with the principles of legal certainty, legality, data quality, exclusion of discrimination and opacity;

- the need for human supervision over decisions made with the help of a computer or artificial intelligence in order to mitigate and prevent violations of the social rights of people;

- the need for effective measures to protect people from irreparable harm, including poverty, extreme poverty or homelessness, as a result of the implementation of artificial intelligence solutions in the field of social services;

- the need for responsibility and accountability of artificial intelligence entities involved in the design, development, deployment or evaluation of artificial intelligence systems;

- a proactive approach to ensure that those people who are affected by the decisions of artificial intelligence can defend their social rights.

This provision acquires particular relevance when it comes to complicating the tasks of ensuring the safety

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