Remediation with Semicoke-Preparation, Characterization, and Adsorption Application

Abstract

Development of low-cost contaminant sorbents from industrial waste is now an essential aspect of the circular economy since their disposal continues to threaten ecological integrity. Semicoke (SC), a by-product generated in large quantities and described as solid waste from gasification of low-rank coal (LRC), is gaining popularity in line with its reuse capacity in the energy industry but is less explored as a contaminant adsorbent despite its physical and elemental carbon properties. This paper summarizes recent information on SC, sources and production, adsorption mechanism of polluting contaminants, and summarizes regeneration methods capable of yielding sustainability for the material reuse.

Influence of Raw Materials and Technological Factors on the Sorption Properties of Blast-Fuel Coke

“…It is noted in the work that the fine fraction of lignite with a size of 212-425 µm without prior physical and chemical treatment has a high adsorption capacity by methylene blue. Thus, the values of adsorption capacity of two untreated lignite samples calculated using the Langmuir isotherm were 286 and 370 mg/g, which was higher than that of activated carbon based on coconut shell (167 mg/g), but lower than that of activated carbon based on coal (435 mg/g) [7].…”

“…The positive experience of improving the characteristics of sorbents when they are modified with alkaline earth metals (Ba, Ca, Mg) is also illustrated by research results [7,21].…”

“…One of the significant advantages of activated carbon is the possibility of improving its properties by modifying it with various metals. This makes it possible to obtain sorbents for extracting certain types of substances [7]. Thus, in works [20] it is noted that the efficiency of removing chromium ions from wastewater reaches 95% when using a carbon-containing sorbent, which is a heterogeneous composite of zero-valent iron and activated carbon.…”

Unravelling the Environmental Application of Biochar as Low-Cost Biosorbent: A Review

“…In the microwave irradiation method, the trapped polar substance molecules in biochar are used to produce dipole to polarization and the electromagnetic field can be transformed into heat energy, generating the heating and volatilization of the organic substances present in the biochar. The main advantage of this method over thermal method is the uniform heating of the biochar, preserving its porous structure [128].…”

A Microwave-Assisted Boudouard Reaction: A Highly Effective Reduction of the Greenhouse Gas CO2 to Useful CO Feedstock with Semi-Coke

“…China is a coal-rich country and implementing carbon neutrality is the country’s strategy for mitigating climate change. Semi-coke, named blue coal, is prepared from Jurassic low-quality coal with reserves of 100 billion tons in China [ 15 ]. As a new type of carbon material with its high fixed carbon content, high chemical activity and low ash content, semi-coke can replace char (metallurgical coke) and is widely used in the chemical, smelting, gasification and other industries.…”