While most of the efforts focus on the recycling of plastic and other industrial manufactured materials and finding alternative and more efficient recycling methods, the potential of utilizing biological waste products as upcycling materials has only recently gained traction.
Textiles: the rapid rise and success of fashion brands in bringing low price & trendy clothes to the market have led to a major shift in consumer behavior. The incomprehensible scale of the garment industry and the sheer quantity of fabrics and trims that are produced for clothing each year is what makes the garment industry so destructive.
Spent Coffee Grounds: produced daily in millions of coffee shops and industrial coffee producers globally. Mainly thrown away and incinerated and therefore creating million of tons of CO2.
Plastic Coated Papers: used daily as ToGo cups, milk containers and other food related packaging. These items are extremely difficult and resource intensive to recycle. Most "bio degradable" packaging products aren't really recycable as they require specific environments. So they end up on landmills and will finally be incinerated creating CO2 and other poiseness gases.
Natural Fibres: from scrap wood, to nut shells, the food production industries create further billion of tons of waste that mostly is incinerated.
There are many more waste materials we are able to collect, recycle and further process into recycable semi or end products. You would be astound what all is possible.