Researchers create eco-friendly detergent from wood fiber and corn protein

Increased public concern about household products' impact on the environment has spurred interest in replacing traditional cleaners containing ingredients such as alkylphenol polyethoxylates and phosphates with natural alternatives. Efforts to date have produced mixed results because these cleaners are difficult to make and hard to rinse off, resulting in high manufacturing and retail costs, as well as potential damage to surfaces and fabrics. Therefore, there is a desire for low-cost, easily produced, effective alternatives that are gentle on the environment and the items they are designed to clean. To address this need, Pengtao Liu and colleagues developed an eco-friendly detergent from ingredients found in abundant renewable sources.

The researchers combined cellulose nanofibers from wood with zein protein from corn to create an emulsion. Cellulose can attract and repel water, so it is effective at forming such emulsions and attracting different types of stains. The zein protein, on the other hand, helps stabilize the emulsion and trap oils. Liu and colleagues then tested the cleaning capacity of the cellulose/zein detergent on cotton fabrics and dishes stained with ink, chili oil and tomato paste. They compared the performance of their new detergent to laundry powder and commercial dish soap solutions with deionized water.

The cellulose/zein detergent was slightly less effective at cleaning the cotton cloth compared to a laundry powder solution of equal dilution (1% detergent or powder by weight). At a 5% concentration, however, the researchers' product was more effective than the 1% laundry powder solution at cleaning each of the stains from the fabric. Microscopic examination showed that the cellulose/zein detergent left no residue on cotton fabric after washing and rinsing, which suggests it would not damage the cloth.

The researchers also tested their detergent's capacity to remove chili oil stains from plates made of ceramic, stainless steel, glass and plastic. Again, the cellulose/zein detergent cleaned almost as well as the commercial dish soap of equal dilution, and at a 5% concentration, their product was superior. On the stainless-steel plates, for example, a 5% solution of cellulose/zein removed 92% of the stain compared to 87% with a 1% solution of commercial dish soap.

The researchers suggested that these results show that their natural detergent could be an efficient, cost-effective and sustainable alternative to synthetic cleaning agents currently on the market.

The authors acknowledge funding from the National Key Research and Development Program of China.