Synthesis and characterization of activated carbon/egg white composite as carbon dioxide adsorbent for green carbon capture

Global climate change has become a serious issue due to the increasing concentration of greenhouse gases, especially CO2 emissions, which trigger global warming and extreme weather conditions. Carbon Capture and Storage (CCS) technology utilizing adsorption methods with activated carbon presents great potential as an economical and environmentally friendly solution. However, the use of chemical activators often raises environmental concerns, highlighting the need for natural alternatives such as soursop leaf extract, which contains bioactive compounds capable of introducing additional functional groups onto carbon surfaces. This research aims to develop an activated carbon composite from coconut shell activated with soursop leaf extract and modified with egg white to enhance CO2 adsorption capacity. The research method was performed as follows: the extraction and phytochemical analysis of soursop leaves, synthesis of activated carbon/egg white (AC/EW) composites, and CO2 adsorption assay. Material characterization was carried out using FTIR, SEM-EDX, BET nitrogen sorption, and PSA. The results showed that soursop leaf-activated carbon met the Indonesian National Standard (SNI). FTIR analysis revealed the appearance of new functional groups N-H and C-N indicating successful surface modification of the AC/EW composite. SEM-EDX analysis indicated enlarged pore morphology and the presence of nitrogen was 5.76%. BET nitrogen sorption analysis showed an increase in surface area up to 232.56 m2/g after activation with soursop leaf extract. PSA results indicate that the composite particle size was in the microparticle range with an average of 691 nm. CO2 adsorption tests demonstrated that the AC/EW composite powder with a 1:1 ratio showed optimal performance with an adsorption percentage of 68.36% and an adsorption capacity of 5.4353 mmol/g. This research successfully demonstrated the effectiveness of combining activated carbon with egg white protein in enhancing CO2 adsorption while supporting green chemistry concepts through the utilization of sustainable organic waste.