Case Studies for Clean Technology Development in the Chemical Industry Using Zeolite Based Catalysts

Abstract

This paper deals with the practical implementation of cleaner technologies in the chemical industry, using two case studies as an illustration. The first case study deals with the removal of NOx and N2O gases over an iron-doped ZSM-5 catalyst developed for tail gas treatment in nitric acid manufacturing. The aim for this case study was to investigate the efficiency of the zeolitic catalyst in the DeNOx process and to compare its catalytic activity with the conventional vanadia-titania. By the experiments carried out, it can be concluded that the new technological developments could significantly contribute to a decrease in environmental pollution. The second case study focuses on zeolite-based catalysts prepared from zeolitic tuff by the impregnation method, for biodiesel production from waste sunflower vegetable oil. The effects of operating and processing variables such as reaction temperature and time were investigated. The results showed that the highest biodiesel yield was 96.7% at an 11.5 MeOH/oil molar ratio, in the presence of 6.4 wt % catalyst at a 50 °C reaction temperature and reaction time of 2 h. The properties of the biodiesel that was produced, such as the viscosity, meet the required specifications of standard JUS EN14214. The common feature of the two different case studies is that both technologies use zeolite catalysts, namely naturally-occurring zeolitic tuff and synthetic ZSM type zeolite catalyst. The examples shown emphasize the importance of the zeolites in clean chemical technologies, which contribute to the protection of the environment.

The Role of Zeolite (Microporous Crystalline Aluminosilicates) In Catalytic Pyrolysis of Waste High- and Low-Density Polyethylene Bags for Production of Fuel and Chemicals: A Review

“…The topic of zeolite products' potential for environmental preservation starts with their industrial manufacture. Since 1954, zeolite manufacturing has attracted industrial interest, and hundreds of thousands of tons of material are produced yearly [46]. The first step in producing a material for environmental protection is the scaling up process because aluminosilicate hydrogels or clay minerals sources that are prevalent in many natural areas and require fewer harmful chemicals as precursors are necessary [47].…”

“…Because low temperatures are used, the temperature helps improve energy efficiency. Zeolites also play a significant role in directly developing environmentally friendly industrial processes [46]. Its production is a product protagonist for biomass conversion, fuel cell development, thermal energy storage, carbon dioxide adsorption, wastewater treatment, and the indirect production of fine chemicals and clean technological steps used in industry.…”

Unravelling Irreversible Adsorbate Thermodynamics through Adsorption Assisted Desorption

“…While the study of Campbell and Sellers focused on metal oxides, there was a basis to extend it to Zeolites a commonly used heterogeneous catalyst in the oil and gas industry for production of gasoline and other useful industrial feedstocks. [9][10][11][12][13][14][15][16][17][18] Studies on the adsorption of hydrocarbons and gases in welldefined zeolite pores with varying porosity was aimed at predicting adsorption entropy in confined porous spaces. The adsorption entropies of these molecules was determined by the occupiable volume incorporating the effect of zeolite network on adsorbed molecule entropy prediction.…”

The Technology of Tail Gases Purifying in Nitric Acid Plants and Design of deN2O and deNOx Reactors—Review

“…% in relation to the amount of nitric acid produced. Thus, without the technology of NO x removal, their concentration downstream of the absorption column may reach even 3000 ppm for low-pressure plants [4,[9][10][11].…”