Evidence map›Paper›PMID 41423504›Full record

ArticleScientific reports2025

Pyrolysis converts urban pruning waste into biochar with soil and climate benefits.

Rafaela de Jesus Paula, Virgílio de Almeida Pereira, Fernando Lopes Latorre, Cinthia Oliveira de Souza Nogueira, Isabela Aroeira de Almeida, Pablo Aislan Freitas E Silva, Osania Emerenciano Ferreira, Robson Pereira de Lima, Augusto César da Silva Bezerra, Alan Rodrigues Teixeira Machado

Abstract read
In one paragraph

Article in Scientific reports, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Rafaela de Jesus PaulaDepartamento de Ciências Exatas, Universidade do Estado de Minas Gerais, João Monlevade, MG, 35930-314, Brazil.
Virgílio de Almeida PereiraWaycarbon Soluções Ambientais e Projetos de Carbono S.A, Belo Horizonte, MG, 30140-080, Brazil.
Fernando Lopes LatorreLatorres Consultoria Ltda, Sete Lagoas, MG, 35702-882, Brazil.
Cinthia Oliveira de Souza NogueiraDepartamento de Ciências Exatas, Universidade do Estado de Minas Gerais, João Monlevade, MG, 35930-314, Brazil.
Isabela Aroeira de AlmeidaWaycarbon Soluções Ambientais e Projetos de Carbono S.A, Belo Horizonte, MG, 30140-080, Brazil.
Pablo Aislan Freitas E SilvaPrograma de Pós-graduação em Ciências Ambientais, Universidade do Estado de Minas Gerais, Frutal, MG, 38202-436, Brazil.
Osania Emerenciano FerreiraPrograma de Pós-graduação em Ciências Ambientais, Universidade do Estado de Minas Gerais, Frutal, MG, 38202-436, Brazil.
Robson Pereira de LimaDepartamento de Geociências, Ciências Humanas e Linguagens, Universidade do Estado de Minas Gerais, João Monlevade, MG, 35930-314, Brazil.
Augusto César da Silva BezerraDepartamento de Engenharia de Transportes, Centro Federal de Educação Tecnológica de Minas Gerais, Belo Horizonte, MG, 30421-169, Brazil.
Alan Rodrigues Teixeira MachadoDepartamento de Ciências Exatas, Universidade do Estado de Minas Gerais, João Monlevade, MG, 35930-314, Brazil. alan.machado@uemg.br.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Urban pruning waste represents an environmental challenge for cities, and its valorization through biochar production in continuous reactors at the industrial scale has scarcely been explored. This study evaluated the conversion of residues in a horizontal pilot-scale continuous reactor. Four biochars (BC1–BC4) were produced under different operational conditions, including various particle sizes (< 10 to < 90 mm), inlet temperatures (140–300 °C), average operating temperatures (290–350 °C), and residence times (60–70 min). All the samples were characterized by their elemental composition (CHN/O), whereas BC4 was selected for more comprehensive analyses, including potentially toxic metals and organic contaminants, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM–EDS), surface area determination (BET), and thermogravimetric analysis (TGA) under air, and recalcitrance index (R50). The carbon sequestration potential was estimated from the Corg and H/Corg ratio. The biochars displayed distinct characteristics. BC1 and BC4 presented the highest carbon contents (71.63% and 70.80%, respectively) and the lowest H/C and O/C ratios. BC3 had the lowest carbon content (47.38%) and the highest ash fraction (38.61%). BC4 had a high degree of carbonization, low ash content (15.40%), favorable atomic ratio (H/Corg = 0.45; O/Corg = 0.13), alkaline pH (8.77), and low specific surface area (4.58 m² g−1). It also complied with European Biochar Certificate thresholds for metals and organic contaminants. Thermal analysis confirmed moderate recalcitrance (R50 = 0.5), and its estimated carbon sequestration potential was 1.62 t CO₂e t−1 biochar. Overall, urban pruning waste biochar has proven safe, stable, and potentially useful for soil improvement and climate change mitigation, although feedstock heterogeneity and logistics remain challenges for large-scale implementation.

Indexed as

CharcoalPyrolysisSoilCarbonCarbon SequestrationCitiesClimateThermogravimetrybiocharCarbonCharcoalSoilAgricultureCarbonCarbon sequestrationConditionerSoilWaste

Identifiers

PMID41423504
PMCPMC12748972

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.