Preparation of biomass film from waste biomass energy corn stalk under carbon neutralization strategy

Abstract

With the rapid development of society and the shortage of non-renewable resources, the effective use of renewable resources has become the focus of people's attention. As an important food source, corn produces a large amount of waste biomass resource corn stalks in its production process. Based on the carbon neutralization strategy, this paper uses corn stover as raw material to efficiently prepare corn stover full-component membranes (CSWM). CSWM is a more environmentally friendly biomass film than commonly used plastic films. Different from the traditional technology, corn straw was used to prepare membrane materials without separating straw cellulose. Corn stover powder was dissolved in four inorganic salt solutions prepared by lithium bromide (LiBr), calcium bromide (CaBr2), zinc bromide (ZnBr2) and zinc chloride (ZnCl2), respectively. The effects of inorganic salt solution concentration, reaction temperature and reaction time on the dissolution rate were investigated, and the optimal dissolution conditions were obtained as follows: 65%, 130 ℃, 45 min; 75%, 130 ℃, 45 min; 75%, 80 ℃, 45 min; 70%, 80 ℃, 45 min, respectively. The prepared four CSWM all have good mechanical properties, hydrophilicity and high porosity. Measured properties were as follows: tensile s trength (21.7–35.5 MPa), elongation at break (6.7–8.6%), water contact angle (0–72°), water content (34.61–45.48%), and porosity (70.95–83.24%). Infrared spectroscopy analysis showed that cellulose, hemicellulose and lignin in corn stover meal reacted with the inorganic solution. Corn stover can be dissolved in inorganic salt solution to make membrane material. Scanning electron microscopy confirmed that CSWM films produced from the four inorganic salt solutions were generally smooth and free of obvious holes or folds. The advantage of this technology is that corn stover can be prepared as membrane material in a short time and through simple experimental operation. The whole experiment is close to the "carbon neutral" process, which helps to reduce carbon dioxide emissions and achieve the purpose of environmentally friendly and high-value utilization of corn stalks. Potential applications for CSWM include building and finishing materials, medical equipment, food processing and packaging, and industrial and municipal wastewater treatment.