A process for the preparation from a partially decomposed organic material like peat a granulated or pelletized sorption medium using low-temperature, thermal activation of the sorption medium to produce a high degree of granule or pellet hardness balanced against an efficacious level of ion-exchange and adsorption capacity, followed by chemical treatment of the thermally-activated sorption material via an acid solution and a salt solution to increase its ion-exchange and adsorption performance while minimizing the transfer of natural impurities found in the sorption medium to an aqueous solution is provided by this invention. The sorption medium of this invention can be used in a variety of aqueous solution treatment processes, such as wastewater treatment.

Adsorbents for microbial remediation of air within a built environment can be used remove volatile organic compounds (VOCs) and improve indoor air quality. The adsorbents include gas-permeable polysaccharide hydrogels containing biochar and bacteria that degrade VOCs to less toxic compounds.

There is described a particulate carbon adsorbent comprising 60 to 90% by wt carbon, wherein the particulate carbon adsorbent is a fibrous pyrolysis product of an organic fraction of waste screenings, and wherein the fibrous pyrolysis product predominantly comprises fibres having a diameter in the range about 10-40 m and a length in the range about 50-500 m. A method of manufacture is also described. The particulate carbon adsorbent is useful in of odour prevention in wastewater treatment and other wastewater processes.